One more for the books on tire vibration,,,, The front hub and bearing assemblies have a lazer code in the edge of the hub.... If the one on the vibrating vehicle is B8, this is most likely the problem, It does not allow the wheel to self center, which will cause a vibration miss diagonised as a tire. A new hub bearing assy with a stamp code of B9 should be installed, I have also found this to cure tire vibration.... I work for Hudiburg Chevorlet in Mid West City, Ok and have been working for several months on these problems. Finally we have a cure, over the last week I have made several different adjustments and changes in the front end of 2 vehicle both with like problems and both customers have stated that there vehicle is more stable, has better control, and no vibration. Please call you local dealership and get your GM Trucks fixed...thanks Gordon for testing my repairs..... Steve
I hope you are right, but your finding almost raises more questions than it answers.
The B8 hub, and the earlier rack and pinion preload seem to address front end shimmy, or vibration problems. Some here are reporting the vibration in the rear. Not saying diagnosis of rear is correct.
My Silverado was built in 1998. Being an early model, would it not also have been built with the B8 hub? If so, why don't I get a vibration/shimmy, or am I just lucky so far? Could I have gotten the B9 hub instead?
I need to know if the vibration/ shutter that your having is at 65 mph.. Is your vehicle a 2 wheel or 4 wheel drive and is it intermitten or constant....If when you drive at 65 mph and the steering wheel starts jerking like you have a tire coming off (or like a worn out front end) the rack will need to be adjusted,, If at 65 mph you can feel a vibration in your seat/passenger seat then the hub bearing are most likely the problem,, If you have a shutter upon take of (hard exceleration) a new leaf spring is being designed to assist to get rid of that, no fix for launch shutter as of yet,, a vibration the can be heard at 42 to 45 mph is the computer shifting the lock up converter early for econemy, this can be change by updating or reprograming the puter with disc 12 thru the tech2 which will change the shift points of the converter and get rid of the vibration buzz,, If you have any more questions that I might be able to help with my email address is SCRAW73160@AOL.com
Thanks for answering a question I didn't ask. I should just stay out of discussion since we have an expert on board.
But for your information, I was wondering why my truck does NOT have the vibration at 65 mph. Since it was made in '98, I just assumed (you know what they say about assume) that I must have the B8 hub. Maybe I don't? Mine is 1500 4x4, recirculating ball steering. No vibration or shimmy at any speed, yet.
Thanks,,, We have been very lucky with the 4X's no problems with steering or shimmy.. Launch shutter is being worked on so stay tuned for future info. If you have any questions, If I dont know the answer I probably know someone who does. and I will help as much as I can. Steve
I took my GMC back to the dealer today for the fourth time about the rear end shimmy. The service advisor told me that he just received a new service advisory (TSB?) from GM this morning concerning this issue (about 15 minutes before I arrived). He couldn't tell me a whole lot about it yet because he hasn't read it fully. In general, he said it relates to changing the rear leaf spring bushings, changing tires (different brand?) and fixing the launch vibration on starts, among other things. If there is anything else, I don't remember it all. I'll call tomorrow to find out more details, what was done to my truck and if vibration and shimmy has been fixed (hopefully).
Service Bulletin Number: 86-74-03 Bulletin Sequence Number: 277 Daate of Bulletin: 9810 NHTSA Item Number: SB602756 Make: GMC Model: GMC Truck Year: 1999 Component: Power train: Transmission: Automatic Summary: Some vehicles may experience a bump/clunk upon acceleration.
There was no further details on their web site. Check with your dealers, he should have further information on this. Just thought I would share this bit of information with everyone. This adresses the issue of a vibration from a start. Later.
I must apologize to everyone for some mis-information that I was given by a service advisor at my GMC dealership and that I posted to this discussion group. I just got my GMC back today and all they did was to re-balance the tires again and road tested the truck saying everything was in spec. You know, service advisors are like salesmen, tell you one thing, do another. I just wish some service advisors were mechanics and would READ and UNDERSTAND their service advisories correctly before they inform their costumers something about their vehicles. They lead me to believe that there was finally a fix from GM. However, there IS an advisory (no number) that was e-mailed to them from GM, but it didn't apply to my truck, nor did the TSB for the vibration (shudder) on start. They lead me down the golden path that maybe GM has finally done something about the rear end shimmy, and I swallowed the bait. I should have know better and waited until the job was completed before I shot my mouth off. It's my fault, and I hope that you all accept this apology and will understand. At least I was happy for awhile. Darn and drat.
I took my truck in yesterday for the shimmy. The dealership re-balanced all of the tires but it still shook. The next step was to measure the tires for any lateral run-outs but they broke the machine that measures it. It will be a week before they get a new part for their machine. I don't believe my luck. Oh well, I'll go to an independent tire retailer and see if they can find any run-outs. The tires are Generals 235/75/r16. I hope it is the tires so I can get rid of these and upgrade to a better brand and larger size. What would be a good size to upgrade to? I'll keep you posted.
HI again, There is no TSB out for checking the Hub and Bearing assys. This is a new found problem on the 1/2 ton 2 wheel drive vehicles....Have your Service Manager call tan Tech Asst Network can only be called by the dealership....Have them ASK about a PI (Product Information), on the B8 vs B9 hub bearings. also on the adjustment on the rack and pinion preloads...The adjustments made to the rack will take out 90% of the shimmy in the steering wheel as when driving and hitting a bump... The hub bearing will take out 98% of the vibration at 65 mph.... The hub bearing that is suspect as being bad is lazer stamped on the outer ring of the backing plate of the hub.. The caliper has to be removed to remove the rotor.. once the rotor has been removed the silver backing plate (the part where the lug studs go thru) has a flat edge about 1/2" thick or slightly less, you might have to rotate the hub to find it.. IT IS THERE it will say B8 and 3 or 4 more digits B8 is bad B9 is good..Going back to the rack and pinion setting, you will have to have patients to get this right, might take 2 to 3 times to get it tight enough.. Have patients with the tech,, This is all new.. I have proven this fix on 7,, 99 pickup as of the end of the work day today.... IF YOUR SERVICE MANAGER WILL NOT CALL TECH ASSITANCE.. TALK TO THE DEALER SHIP GENERAL MANAGER MAKE IT HAPPEN.. THIS INFO IS NOT BEING PASS OUT THEY WILL HAVE TO SEARCH FOR IT. UNTIL A TSB IS RELEASE.. THIS REPAIR HAS ONLY BEEN AVAIL SINCE MONDAY AND BEEN PROVEN BY THIS TECH 7 TIMES,,, IF YOU CAN'T GET ANY HELP FROM YOUR DEALERSHIP CALL THE 1800 CUSTOMER SERVICE IN YOUR OWNERS BOOK AND TELL THEM THIS INFO.
A CHEVORLET MECHANIC TRYING TO HELP (THIS WORKS) STEVE C.
Oh yeah on your other vehicle how many time did it take to get the tire balance correct.... The tires are balanced and the vibration is still there, leave the tires alone its the truck think about it.......tell the service writer the same thing (dont you trust your tech about the work they do and how often do your tires need balancing anyway since it doesnt change anything dont have them waste your time with it) Sorry hard to get off this soap box Steve
Hi all I took my 99 GMC ext Z71 in for the vibration noise at 40 mph and all they did was drive another new truck on the lot and say it had the same noise so it was normal!! I also told them when braking hard you could hear a clank about 2-3 times 1/2 sec apart. It sounded like u-joint clank when you are parked and go from Park to D or R. They said the rear rotors were bad and put new ones on. Well not the truck vibrates from 25 and up. It feels like a "flat" spot on the tires like in the old days and you first got in your truck on a cold day. I have a friend who is a Chevy mech and he said the rear rotors look used. They are pitted, and rusted, If you look where the pads hit you will see some funny dis-coloration in the rotor. Real strange. I feel I an getting the run around, I will bet if I told they it was using 1qt of oil in 500 miles they would say that is normal.
Not a happy camper. Almost wishing I bought a Ford.
The vibration that you have described is exactly what I have been talking about,,, It has been miss diagonised as the drive line or rear tires, It is in the front trust me.. the front hub bearing assemblies are causing the vibration they do not allow the front tires to center correctly this is a proven fact with B8 hubs... Some one needs to look at the front hub and verify the number stamped on the hub, NOT THE PART NUMBER!!!! The next time you go to the dealership have them check the stamp code on the hub stand over there sholder and see for yourself...If its a B8 get them replaced... Damn I am starting to hate Chevy Tech that are so greedy they wont take the time to check these thing...Thats what gives us bad names and the biggest reason the the customers wont go back after the warrenty runs out.. I am sorry folks Sorry for the way your dealership are handling this problem espically when there is a fix steve
I tried posting this once before, but I guess it got lost in cyberspace. So if there is a double posting, SORRY.
Scraw,
I took your postings to the dealer yesterday, and this is their responce. They basically said that they will not, are not, can not, nor be interested in hearing of, or respond to anything that is/was posted on any web site, bulletin board or discussion group. It has to be written is stone, and it has as to come to them either as a service advisory, service letter, from tech support or TSB delivered to them via telephone from GM tech support, fax, e-mail or by snail mail from GM or GMC. They said. This was/is their policy. I personally do not think they will ever take the time to call either your dealership nor tech support because of this policy. I also tried the only other GMC dealer in this area. I talked to the service manager and he said that this was his dealerships policy, also. What I don't understand is, why are they so pig headed that they won't take the helpful information handed to them from other sources and take the time to ask another dealership for assistance. So that, if and when they do run into a problem, there may have been a procedure that was overlooked or that they (the other dealership) may have a solution for it. Sure looks like that I may have ran into a problem (stone wall) as far as getting any help from any of these two dealerships. It just HAS to be OFFICIAL from GM, not from the web. As a side note, they both were appreciative of you and your dealerships hard work and dedication but, their hands are tied by their dealerships policy. I guess they would rather go on going step by step, by the book, fix by repair and replace parts until they get it right, instead of investigating and diagnosing the problem like you have done on your own. I would suggest that YOU document all the steps you used, all the procedures that you have done so far, what was done, parts involved, etc. and present a strong case to GM. May be now there will be a service advisory, service letter or TSB issued, just to get this dealers off their [non-permissible content removed] and get moving. All I know is that all four of my aluminum rims are getting pretty marked up on the inside bead area from all the wheel weights that have been use so far, and the ride is no better at 62 to 72 MPH. Taking my truck to Oklahoma from south central Florida would be out of the question, just to have my truck taken care of properly would be going alittle bit to far wouldn't you think? KEEP UP THE GOOD WORK STEVE and may be something will come out of this soon, hopefully. Got to get off my soap box. Later.
PS, I was told that the muffler (looks like a water heater to me) rubber mounts could/has caused something like this before? True or false?
My dealership says the same thing that Knobby says. They cannot touch the 99 Silverado unless a procedure has been issued from GM. All they can do is assign a TAN number and wait. Someone like Steve has got to get this to Tech Support so the dealers can act.
if your vehicle is still vibrating from 42 to 45 mph get your computer updated....not changing my mind on these items there are 4 different vibrations and these stupid spineless dealerships wont help ticks me off Steve
Sorry,, exhaust system has not been a problem just one method of verifing 1 of the 4 problems... I just wish tech asst would get out the tsb they said is was on the way but as of yet I havent seen it.......good luck and remember there is a fix and it will be done soon....
Ps I might be coming to kissimmee at christmas so if its not fixed by then I'll look you up
All, Read the whole list. Most have same question. There are three problems: 1) front end shimmy-caused by Rack and pinion preload not properly set AND B8 vs B9 hubs (B8 not self centering causing a vibration B9 is self centering and doesn't vibrate)fix- adjust R&P preload and replace B8 with B9 hubs 2) Rear end shimmy at 60-70 mph-only reported in 2wd w/ 3.43 dif locking or not-appearantly caused by an excessive u-joint angle in the back half of the drive shaft. fixes: change the angle with shims or new motor-tranny mounting brackets. U-joints are not constant velocity and create felt vibrations depending on rpm, load and angle. Fix2: replace the 3.43 dif with a 3.7-get ready for better pulling but less mpg's (-1 or -2 mpg at worst) 3) Bad tires: the General brand tire that came as oem appears to have a run out problem- FIX: replace tire with new oem Firestone brand. 4) Another problem I've been reading about is a squeak caused by two things. Thing1: bad chasis mounts or improperly torqued chasis bolts-fix: retorquing the bolt solves problem short term-replacing mounting pad and bolt provides those reporting a more long term repair (no new complaits after doing this) Thing2: Suspension springs front and rear rub against spring bracket when compressed (ie. going over a bump)causing a high pitched metalic squeal. Fix: have a welder move the spring bracket 1/2 inch more away from the spring. (personaly don't like this option but has been reported to clear up squeak). Keep working at it Steve, we are listening.
Guys, Sorry, forgot this one. Engine/transission growl at 35-40 MPH: caused by the locking plate prematurely moving into position in automatic transmissions fix: GM actually has a fix for some early and possibly later VINS at this time. Take your truck in and get the program flashed. One report indicated that not only did the growl go away but the truck felt like it had better performance and power.
Don't forget this one : The vibration that occurs around 1400-1600 rpm in first gear and less noticeable in second. Very noticeable pulling a load or going uphill. My truck a 1500 2wd extended cab with 5.3 and 3.42 locking rear has this problem and none of the other vibrations, shimmys or growls. My dealer is going to try shims on the driveline to see if this helps but from what I've seen here its been tried without results. I guess the dealer needs to document all attempts to correct this problem.
On 3-1-99 I took delivery of a 1999 Silverado LS, 1500 extended cab from Hudiburg Chev. in Midwest City, OK. For the first 1000 mi. I didn't have a problem and was happy with my purchase. Then the problems started in this order. 1. a rumble - vibration coming from the floor in the area of the transmission at 45 mph. 2. A shutter - shaking in the rear of the truck when taking off from a stop, labeled as a "launch shutter" by the service dept. 3. A vibration at 65 mph, mostly on the passenger side of the truck, causing the cups in the cup holders to jump wildly. 4. Finally, a violent shaking of the steering wheel on rough pavement, sometimes so bad that slowing down and almost stopping was the only way to control it. As you can see, I have had my problems! Through all of this Hudiburg Chev. service dept. has bent over backwards trying to correct the problems. Steve (scraw) has put alot of time and effort on my truck and I appreciate it! I'm sorry that the rest of you with similar problems don't have the dealership and service dept. that I have been lucky enough to have. Today my truck is 98% better that when my problems began and I again am able to enjoy driving it. My advice to you Silverado owners with problems is to listen to Steve or drive to Oklahoma and Hudiburg Chevrolet!!! Steve knows what he is talking about. One more item I would like to bring up. I had the opportunity to talk to a engineer from GM who came to Hudiburg to observe the problems with my truck. I asked about an extended warranty because of the problems I was having. He said there was such a thing and he would get back with me. After a couple of weeks, I was told they wouldn't give me one because I didn't have enough miles on my vehicle at this time. I would like to know what the rest of you Silverado owners out there with problems think about this. Again, thanks to Hudiburg Chev. and expecially to Steve for all the help they have given to me.
I thought I would let everyone know that I have arranged with the other GMC dealer to rule out any General tire imbalance. They will take all four tires and rims over to the local Cadillac dealer, where they have a HUNTER road force load measurement system tire balancer and check for any run-out on them. I'll also see if I can talk them into looking at the front wheel hubs while the rims are off to check for the B8's. Will let everyone know what happens on this one later.
To Phil;
I just hope that it is bad GENERAL tires. However, of all the tire manufacturers I dislike, it's FIRESTONE. Ever since they were bias-ply tires and the infamous FIRESTONE 500's. I would rather have Michelin's or BFG's as a replacement tire even if I have to share to cost for them. The dealer has so far replaced the drive shaft and shimmed the rear of the transmission at the rear mount, but I haven't seen in the w/o where they replaced the mount itself. As for replacing the 3:42 rear end gear ratio to 3:73's, I would rather not at this time unless it's the last resort. I like going down the turnpike or interstate at ~75 MPH and still have the engine turn alittle less than 2,000 RPM's.
I guess Steve (scraw) would be the best to answer this. How many of the new truck owners are actually having a problem? What percentage of the Oklahoma customers are bringing their 3.42 ratio trucks in for shakes and how many are bringing their trucks back for the front end shimmy?
Knobby & mike38- sounds like you have the rack preset problem. It may (just a guess) have been caused by a poorly calibrated tool on the assembly line. If its just due to low preset tension on the rack it could be worth looking into. The B8 hub is the other half of the front end shimmy. I don't have a guess for that one other than parts on hand (even the wrong one that still works) equals production quotas stay up. I'll agree that the tires are more than likely not THE problem; more a symptom of the problem both front and rear.
As far as a percentage, per truck we sell the 2 wheel drive truck are the least sold, and the only ones we are haveing problems with, and the percentage of them are being BS'ed by the sales men,,,, But probably 50%....Have the problems... 4x4 and Z71's are some of the best with very few or,, little to no complaints,,, 3/4 ton trucks are having no problems as of yet cross my fingers,, First out of the box trucks are the biggest problems and there starting to wear tires due to this bounce, chopping the inside tread... Ok to date In the state of Oklahoma I have personelly repaired 7 of these trucks,,, I have overseen the repair of 1 launch shutter and confermed it.... SMOOTH AS GLASS ....Tomorrow I have to go to school to learn about the new braking system,,, From what I understand about the class I might be giving a few lessons myself... I really hope to share some info with the GM school and the district field engineer, Hopefully with what I have done and the repairs I have made we can get some info out to the field so we can get some of your trucks fixed...I hope this info helps and answers your question STEVE C
I hope GM will have a fix long before you come to Kissimmee (wishfull thinking on my part) at Christmas. If you do? I live ~100 miles south of there. Take the Florida Turnpike from Kissimmee, and go south to exit 142.
I went to an independent tire dealer to check on run-outs. They said I had a tire that was marginal. I then went back to the dealer and spoke to the shop foreman and he agreed to take my truck and replace all of the tires with a different brand from another truck to try to eliminate the tire problem. Hopefully this is what the problem is. The foreman said they have had a lot of trouble with General tires with the trucks as well as cars. Get this, a local General Tire distributor here in town will not do warranty work for these tires due to the fact that the tires are so cheap the tire dealers won't even sell them. The dealer wouldn't even give me anything on a trade for some other tires. It's too bad that GM puts this kind of product on their flagship vehicle. I guess it is what I get for ordering an SL--cheap truck gets cheap tires. I'll keep you posted next week on the tire swap.
Scraw-- My truck was built in March. Do you think I could have the bad hub problem? I don't feel anything in the steering wheel at all.
Isn't General the one on strike?? I hear they are having big problems with tires do to the fact they have hired a bunch of workers that have no clue how to make tires. There has been radio commercials from the Union??..saying please don't buy Ford Products and call them and ask that they don't use these tires. Maybe GM is having the same problem?
Hopefully mine has the Firestones?? for 2000 On/Off road tires.
I've read several posts slamming the firestones too, but my P265 Wilderness A/T's have been pretty good in all areas, so far. They ride quiet, don't shake or vibrate, have decent traction, look good too.
Interesting thing about tires, is that they are manufactured pretty much as they always were, by hand. It's more art than science. They use the same molds, but the plys are hand laid, and the vulcanizing process (curing) is not always consistent. Doesn't matter what brand you are talking about. So the main thing when you buy new ones, is to insist on replacements right away if you feel something is not right. There will always be good sets and bad sets.
if your still shaking,,,, the combination of problems,,, the rack and pinion preload, and the hubs... Most likely the hub bearings, not felt in the steering wheel but in the seat and visably in the cup holder. bug them till they check for B8 or B9 hubs.... and dont be surprized if they find B8's steve
We sent the vehicle to a local spring shop and had them add a leaf, we also kept the shims we installed in between the spring and differential.. when we got the truck back and test drove it... HAMMER HAMMER straight to the floor and it was just like glass... Wonderful feel and no shake, vibration, shutter, no hum, no nothing Just 1 perfect TRUCK,,,, Made Gordon happy Steve
Glad to hear that your launch stutter went away. I just want to be clear on what was done. You had both shims and a new leaf added to your existing springs. This solved your problem? What was your engine, trans, & dif options?
I have a 1500 LS, 4.8L, 3.42 gear w/lock diff and a vibration problem in the rear. The Dealer upon my first visit, they rebalanced to no avail and ordered 4 new tires. They replaced all 4 tires and one wheel. I noticed no change, and thought something was up since a dealer never volunteered so much so quickly for me. The latest is for me to drop off my truck for a couple of days so that they can take measurements of the vibration and drive line specs. This data will be given to a GM service tech to review and he will get back to the Dealer on how to fix. The Dealer has told me they have tried this on some other trucks with some sucess. But I have not been told what they actually fixed.
After filing complaint with the State Attorney General's Consumer Affairs Division, Dealer agreed to have drive shaft balanced. They had two trucks with the 65+ shake and claim that they just fixed one truck by sending the drive shaft to a heavy duty machine shop for balancing. Will take about 3 days. Amazing that they actually can work on these trucks without voiding the warranty. AG's office laughed at me when I told them that one. Will keep you posted. Provided me a new Dodge Ram 1500 as a rental. You figure. One blunder after another. Wish Steve was down in Alabama.
gave service rep info on b-8 and b-9 hubs,said he would call tech support,so far no word back from them, call G.M. and got a complaint number lady said this a very common complaint, I can"t understand why G.M. can"t come up with the a way to fix this .
The hub and bearing assembilies are nation wide back order,,,, HMMMM tells me that My word is getting out,,,, I went to school last thursday and was not inpressed with the info they were offering,,, There still at square 1 on all the stuff, seems that the info avail has not been passed by tech asst or tech asst hasn't tested it yet to confirm,,,,I have had calls from other dealers on how to make the repair, been on the phone a lot so the word is getting out Keep the faith,,,, STEVE C
Well I read all 100 links, at least most of them - anyway tomorrow I get my new 2000 LT with a 3.42 an I'll find out if anything has changed. I'm trying to keep a pos - mind though. Its very hard since I ordered the truck in March and the Dealer sold it May 10 (to someone else) the day after it showed up. The Dealer didn't tell me about it being sold until May 24 after I damn near strangled him.
Service Manager called today and said the information he is getting from technical assistance at GM now related to two problems to correct the 65+ shake. 1.) The hubs on the front end should be replaced with updated hubs. 2.) A new tire has been developed and will be shipped late next week by General Tire to address the added stress from the new "ridged frame." Tech Support according to the Service Mgr. says this should remedy the shake felt in the seats. He says that hopefully within two weeks both the hubs and tires should be at his service department. Since I filed a complaint with the Attorney Generals office, I will not have to wait for a TSB from GM. He says he has three other trucks with this problem. I keep hoping the next "fix" is the one. This sounds more creditible though having read Steve's input on the hubs. Tires really have me puzzled though. How could more ridged frame affect tire stress that much?
I had my tires replaced with some other brand this week and my General's were in bad shape. Two of them had lateral run outs. I was not able to negotiate an upgrade on some other tires so I'll get a couple new General's in a couple of weeks. The service bulletins seem encouraging and I hope this problem is resolved soon. Thanks to Steve and others like him, we might be riding smooth soon.
Comments
The B8 hub, and the earlier rack and pinion preload seem to address front end shimmy, or vibration problems. Some here are reporting the vibration in the rear. Not saying diagnosis of rear is correct.
My Silverado was built in 1998. Being an early model, would it not also have been built with the B8 hub? If so, why don't I get a vibration/shimmy, or am I just lucky so far? Could I have gotten the B9 hub instead?
Thanks in advance.
But for your information, I was wondering why my truck does NOT have the vibration at 65 mph. Since it was made in '98, I just assumed (you know what they say about assume) that I must have the B8 hub. Maybe I don't? Mine is 1500 4x4, recirculating ball steering. No vibration or shimmy at any speed, yet.
I took my GMC back to the dealer today for the fourth time about the rear end shimmy. The service advisor told me that he just received a new service advisory (TSB?) from GM this morning concerning this issue (about 15 minutes before I arrived). He couldn't tell me a whole lot about it yet because he hasn't read it fully. In general, he said it relates to changing the rear leaf spring bushings, changing tires (different brand?) and fixing the launch vibration on starts, among other things. If there is anything else, I don't remember it all. I'll call tomorrow to find out more details, what was done to my truck and if vibration and shimmy has been fixed (hopefully).
Service Bulletin Number: 86-74-03
Bulletin Sequence Number: 277
Daate of Bulletin: 9810
NHTSA Item Number: SB602756
Make: GMC
Model: GMC Truck
Year: 1999
Component: Power train: Transmission: Automatic
Summary: Some vehicles may experience a bump/clunk upon acceleration.
There was no further details on their web site. Check with your dealers, he should have further information on this. Just thought I would share this bit of information with everyone. This adresses the issue of a vibration from a start. Later.
The tires are Generals 235/75/r16. I hope it is the tires so I can get rid of these and upgrade to a better brand and larger size. What would be a good size to upgrade to? I'll keep you posted.
Truck tires are tough, but street tires are comfortable.
IF YOUR SERVICE MANAGER WILL NOT CALL TECH ASSITANCE.. TALK TO THE DEALER SHIP GENERAL MANAGER MAKE IT HAPPEN.. THIS INFO IS NOT BEING PASS OUT THEY WILL HAVE TO SEARCH FOR IT. UNTIL A TSB IS RELEASE.. THIS REPAIR HAS ONLY BEEN AVAIL SINCE MONDAY AND BEEN PROVEN BY THIS TECH 7 TIMES,,, IF YOU CAN'T GET ANY HELP FROM YOUR DEALERSHIP CALL THE 1800 CUSTOMER SERVICE IN YOUR OWNERS BOOK AND TELL THEM THIS INFO.
A CHEVORLET MECHANIC TRYING TO
HELP (THIS WORKS) STEVE C.
I took my 99 GMC ext Z71 in for the vibration noise at 40 mph and all they did was drive another new truck on the lot and say it had the same noise so it was normal!!
I also told them when braking hard you could hear a clank about 2-3 times 1/2 sec apart. It sounded like u-joint clank when you are parked and go from Park to D or R. They said the rear rotors were bad and put new ones on. Well not the truck vibrates from 25 and up. It feels like a "flat" spot on the tires like in the old days and you first got in your truck on a cold day. I have a friend who is a Chevy mech and he said the rear rotors look used. They are pitted, and rusted, If you look where the pads hit you will see some funny dis-coloration in the rotor. Real strange.
I feel I an getting the run around, I will bet if I told they it was using 1qt of oil in 500 miles they would say that is normal.
Not a happy camper. Almost wishing I bought a Ford.
steve
tell them to call in the results of the eva test to tech asst and get the fix
Scraw,
I took your postings to the dealer yesterday, and this is their responce. They basically said that they will not, are not, can not, nor be interested in hearing of, or respond to anything that is/was posted on any web site, bulletin board or discussion group. It has to be written is stone, and it has as to come to them either as a service advisory, service letter, from tech support or TSB delivered to them via telephone from GM tech support, fax, e-mail or by snail mail from GM or GMC. They said. This was/is their policy. I personally do not think they will ever take the time to call either your dealership nor tech support because of this policy. I also tried the only other GMC dealer in this area. I talked to the service manager and he said that this was his dealerships policy, also. What I don't understand is, why are they so pig headed that they won't take the helpful information handed to them from other sources and take the time to ask another dealership for assistance. So that, if and when they do run into a problem, there may have been a procedure that was overlooked or that they (the other dealership) may have a solution for it. Sure looks like that I may have ran into a problem (stone wall) as far as getting any help from any of these two dealerships. It just HAS to be OFFICIAL from GM, not from the web. As a side note, they both were appreciative of you and your dealerships hard work and dedication but, their hands are tied by their dealerships policy. I guess they would rather go on going step by step, by the book, fix by repair and replace parts until they get it right, instead of investigating and diagnosing the problem like you have done on your own. I would suggest that YOU document all the steps you used, all the procedures that you have done so far, what was done, parts involved, etc. and present a strong case to GM. May be now there will be a service advisory, service letter or TSB issued, just to get this dealers off their [non-permissible content removed] and get moving. All I know is that all four of my aluminum rims are getting pretty marked up on the inside bead area from all the wheel weights that have been use so far, and the ride is no better at 62 to 72 MPH. Taking my truck to Oklahoma from south central Florida would be out of the question, just to have my truck taken care of properly would be going alittle bit to far wouldn't you think? KEEP UP THE GOOD WORK STEVE and may be something will come out of this soon, hopefully. Got to get off my soap box. Later.
PS, I was told that the muffler (looks like a water heater to me) rubber mounts could/has caused something like this before? True or false?
I just wish tech asst would get out the tsb they said is was on the way but as of yet I havent seen it.......good luck and remember there is a fix and it will be done soon....
Ps I might be coming to kissimmee at christmas so if its not fixed by then I'll look you up
See ya
Read the whole list. Most have same question. There are three problems:
1) front end shimmy-caused by Rack and pinion preload not properly set AND B8 vs B9 hubs (B8 not self centering causing a vibration B9 is self centering and doesn't vibrate)fix- adjust R&P preload and replace B8 with B9 hubs
2) Rear end shimmy at 60-70 mph-only reported in 2wd w/ 3.43 dif locking or not-appearantly caused by an excessive u-joint angle in the back half of the drive shaft. fixes: change the angle with shims or new motor-tranny mounting brackets. U-joints are not constant velocity and create felt vibrations depending on rpm, load and angle. Fix2: replace the 3.43 dif with a 3.7-get ready for better pulling but less mpg's (-1 or -2 mpg at worst)
3) Bad tires: the General brand tire that came as oem appears to have a run out problem- FIX: replace tire with new oem Firestone brand.
4) Another problem I've been reading about is a squeak caused by two things. Thing1: bad chasis mounts or improperly torqued chasis bolts-fix: retorquing the bolt solves problem short term-replacing mounting pad and bolt provides those reporting a more long term repair (no new complaits after doing this) Thing2: Suspension springs front and rear rub against spring bracket when compressed (ie. going over a bump)causing a high pitched metalic squeal. Fix: have a welder move the spring bracket 1/2 inch more away from the spring. (personaly don't like this option but has been reported to clear up squeak). Keep working at it Steve, we are listening.
Phil
Phil
Sorry, forgot this one.
Engine/transission growl at 35-40 MPH: caused by the locking plate prematurely moving into position in automatic transmissions fix: GM actually has a fix for some early and possibly later VINS at this time. Take your truck in and get the program flashed. One report indicated that not only did the growl go away but the truck felt like it had better performance and power.
Phil
1. a rumble - vibration coming from the floor in the area of the transmission at 45 mph.
2. A shutter - shaking in the rear of the truck when taking off from a stop, labeled as a "launch shutter" by the service dept.
3. A vibration at 65 mph, mostly on the passenger side of the truck, causing the cups in the cup holders to jump wildly.
4. Finally, a violent shaking of the steering wheel on rough pavement, sometimes so bad that slowing down and almost stopping was the only way to control it.
As you can see, I have had my problems! Through
all of this Hudiburg Chev. service dept. has bent over backwards trying to correct the problems.
Steve (scraw) has put alot of time and effort on my truck and I appreciate it! I'm sorry that the rest of you with similar problems don't have the dealership and service dept. that I have been lucky enough to have. Today my truck is 98% better that when my problems began and I again am able to enjoy driving it.
My advice to you Silverado owners with problems is to listen to Steve or drive to Oklahoma and Hudiburg Chevrolet!!! Steve knows what he is talking about.
One more item I would like to bring up. I had the opportunity to talk to a engineer from GM who came to Hudiburg to observe the problems with my truck. I asked about an extended warranty because of the problems I was having. He said there was such a thing and he would get back with me. After a couple of weeks, I was told they wouldn't give me one because I didn't have enough miles on my vehicle at this time.
I would like to know what the rest of you Silverado owners out there with problems
think about this.
Again, thanks to Hudiburg Chev. and expecially to Steve for all the help they have given to me.
I thought I would let everyone know that I have arranged with the other GMC dealer to rule out any General tire imbalance. They will take all four tires and rims over to the local Cadillac dealer, where they have a HUNTER road force load measurement system tire balancer and check for any run-out on them. I'll also see if I can talk them into looking at the front wheel hubs while the rims are off to check for the B8's. Will let everyone know what happens on this one later.
To Phil;
I just hope that it is bad GENERAL tires. However, of all the tire manufacturers I dislike, it's FIRESTONE. Ever since they were bias-ply tires and the infamous FIRESTONE 500's. I would rather have Michelin's or BFG's as a replacement tire even if I have to share to cost for them. The dealer has so far replaced the drive shaft and shimmed the rear of the transmission at the rear mount, but I haven't seen in the w/o where they replaced the mount itself. As for replacing the 3:42 rear end gear ratio to 3:73's, I would rather not at this time unless it's the last resort. I like going down the turnpike or interstate at ~75 MPH and still have the engine turn alittle less than 2,000 RPM's.
To SCRAW;
I hope you're right.
When I think of what my first house costs compared to what my new truck costs...kinda turns the stomach!
$43K in Can. money though...right??
So about 1/2 American?
But I don't have a growl, shimmy, shudder, vibration, so I didn't get it reflashed for that.
It seems impossible, I know.
Knobby & mike38- sounds like you have the rack preset problem. It may (just a guess) have been caused by a poorly calibrated tool on the assembly line. If its just due to low preset tension on the rack it could be worth looking into. The B8 hub is the other half of the front end shimmy. I don't have a guess for that one other than parts on hand (even the wrong one that still works) equals production quotas stay up. I'll agree that the tires are more than likely not THE problem; more a symptom of the problem both front and rear.
Phil
STEVE C
Get this, a local General Tire distributor here in town will not do warranty work for these tires due to the fact that the tires are so cheap the tire dealers won't even sell them. The dealer wouldn't even give me anything on a trade for some other tires. It's too bad that GM puts this kind of product on their flagship vehicle. I guess it is what I get for ordering an SL--cheap truck gets cheap tires.
I'll keep you posted next week on the tire swap.
Scraw--
My truck was built in March. Do you think I could have the bad hub problem? I don't feel anything in the steering wheel at all.
I hear they are having big problems with tires do to the fact they have hired a bunch of workers that have no clue how to make tires. There has been radio commercials from the Union??..saying please don't buy Ford Products and call them and ask that they don't use these tires. Maybe GM is having the same problem?
Hopefully mine has the Firestones?? for 2000 On/Off road tires.
Tim
Interesting thing about tires, is that they are manufactured pretty much as they always were, by hand. It's more art than science. They use the same molds, but the plys are hand laid, and the vulcanizing process (curing) is not always consistent. Doesn't matter what brand you are talking about. So the main thing when you buy new ones, is to insist on replacements right away if you feel something is not right. There will always be good sets and bad sets.
I was wondering what you did to fix the launch shudder? Leaf springs?
Phil
Hope all is fine
Tim
I keep hoping the next "fix" is the one. This sounds more creditible though having read Steve's input on the hubs. Tires really have me puzzled though. How could more ridged frame affect tire stress that much?