Chevy Silverado/GMC Sierra's w 8100/Allison
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Comments
Bob
Buyback update ... I acceped the 5/100 warranty.I couldnt make the trans malfunction for the past couple of months so all I've got to complain about is the engine knock.Oh well...I really love the truck anyway.
kip
Hey, I remember a few posts back you guys were talking about bigger tires. Without having to make any modifications, what sizes are working for you guys?
I upgraded to 265 75's on my HD. No need for speedo or abs recal. One good thing is the abs is no longer over sensitive like it was with the 245's...that was a big plus!!
Not to mention the 265's really fill out the wheel well nicely IMHO.
Others are running 255 85's with great sucess as well with the stock rims.
Bob
I'll be making a dealer appointment for April 5 (soonest I can get ahold of another vehicle to drive), to look at this and a couple of other things. Like the Emergency Brake not engaging until it's almost to the floor and there's an odd high pitched whining sound on startup when it's cold which goes away as soon as the temp begins to increase. It almost sounds like a squeaky belt, but it's more "metallic" sounding than a belt and it's coming from underneath the truck, not from the front. A couple of people have suggested it sounds like the heat shield is loose. We'll see.
As far as my gas mileage goes, I got 11.7 on 3 tanks of Mobil Regular Unleaded - average speed about 50 mph (some highway, some 40-45 mph zones). I'm experimenting with Mobil Special Unleaded now. Have run 1.5 tanks so far - got 11.1 mpg on the first one, not quite as good at the Regular Unleaded.
I'm thinking about signing up on AllData to get detailed TSBs since the geocities site was taken down. Anyone have an opinion on it's usefulness?
'01 2500HD ex-cab 4x4 /4.10
kip
Also I am wondering at what point should one move from a 1500 pickup to the 2500 HD. I have read in several discussions of the lighter duty trucks pulling 5000 - 6000+ pounds "no problem". I have a '99 Ram 4x4 with 3.55 gears and the 360, it is not an impressive puller with even a 4000 pound load. Is the higher gearing really that bad for towing versus 4.10s? I agree with the above statements that the HD will be the safer way to go especially when moving up in towing weight.
Upgrading is all up to you, however I don't think I would want a half ton pulling 6,000lb loads every few weekends, like a camper or boat or something like that. Sure the truck can move it, but after a while, the stress on the drivetrain wear it out not to mention your nerves. Trust me, been there done that, never gonna do that again!! We upgraded our truck because we knew we would be selling the boat and buying a 5er sometime. As it turns out that sometime is this year!! Glad I have a truck that I know will pull this 5er. It weighs about 7500 lbs before food, gear, etc. I figure after the wife gets done loading all of the "necessities" we will be close to the GVW of the trailer at 10,000lbs!!
By the way I got the 4.10 gears in my truck because I was planning on upgrading the tires. I am getting the same mileage as others with the 8.1L and 3.73's and other people are reporting the same thing. Get the 4.10's and don't look back!!
Bob
kip
And, what exactly does overly sensitive ABS feel like?
-David
I ordered my '99 Ram QC and paid invoice, I like ordering because I get what I need/want and don't have to fight with a salesman over bells & whistles I don't want to pay for (and I don't mind waiting). Planning on ordering a 2003, will be checking some of the other discussions to see if there is early news on changes and improvements. Hopefully I will be able to get close to invoice again.
Vehicle data: 2001 GMC 2500HD LT 8.1L w/Allison transmission.
MPG... most of these HD speedometers are reading fast by 2-3 mph with the stock 245's. There are big discussions over on the dieselpage.com about this. Many of the guys are comparing speedo to their GPS units and finding the diff. My speedo reads 3 mph faster. Now if I up graded to 265's my speedo would be just about perfect.
Also, remember if the speedo is reading fast, we are actually getting better MPG that what we believe and we are getting to the end of our warranties sooner than 36K!! Hmmm...something to ponder!! A GM money saving scheme?
Good Luck,
Kyle
-David
I didn't say Chevrolet does not require recalibrations for 265's, just stated it wasn't necessary, I should have stated it was my opinion, sorry. Chevrolet doesn't even want you to upgrade your tires. In fact there is a tsb stating if you are complaining about performance or transmission shifting you must have the 245's on before they will even look at it.
I have not checked my speed with a GPS, but have read that the rolling distance between the 245's and 265's is so little (like 2% or 3%) that it is not necessary from other peoples opinions to recal, that is why I didn't. Sorry should've explained better in my earlier post. You can have the speedo recalibrated for 265's, at least that is what my service manager told me. However it is $100!! No thanks, I'll put that towards the higher gas prices thank you.....
To clarify the over-sensitive abs I had and others have reported. It is when you are braking and go over the slightest bump and your abs kicks in pulsating the brake pedal and then not applying as much force to the brakes so you don't slow down as quickly. Now with the 265's when braking going over minor bumps or expansion joints, the abs does not kick in extending my stopping distance. Hard to explain I guess, but when ever my abs kicked in with the 245's on dry roads, my stopping distance increased!!
I didn't notice any shifting issues from the Allison going up to 265's. I have a hard time believing there would be a cooling issue with the Allison while towing or empty as the 265's don't decrease your rpms by much, maybe 200 rpms?? I am not an expert, but the two Allison guys on the diesel page haven't stated that it will be a problem. I think one of them even has upgraded his tires to 265's or 285's!!
Bob
-- Don
Can't see paying anyone to do that when I can do it myself in 10 minutes.
Do they ship the Alison with synthetic ATF? The owner's manual talks about the Castrol transynth or whatever it's called, but it doesn't say if that's what's actually IN IT. I figure I'll just prime the filter (fill it) first, especially since that Alison supposedly has circulation problems anyway.
As for the transmission filter, there is a magnet on the filter that needs to be removed (right on the top around threaded hole) cleaned & placed on the new filter.
-Eric
I also replaced the Allison filter and, as has been stated here previously, it pays to shop. I got quotes from GM ranging from 18.00 to 44.00. An Allison dealer charged 8.25. I bought three. By the way, Allison told me #29537268 has been discontinued. The new number is #29539579. I can see no difference from outside appearance.
If you'll check your manual, (page 7-27) you'll see that DEXRON-III is the prescribed fluid. Castrol TranSynd is the recommended fluid if you switch to synthetic. There's a lot of information about it on the Allison site. Happy wrenching.
Bob; Thanks for the info. No problem about the wait. Because of my situation I also have limited access to my computer. I stopped by my dealer today and asked about recalibrating the speedometer after a 265 upgrade. At first they were all, "Yeah, yeah, ABS" and "computer controls everything and yada, yada". But when I pressed, "You mean for just one tire size"? they were'nt quite so affirmative. I'll just keep checking.
BTW, does anyone know of or if GM techs use an all-in-one device for diagnostic and recalibration? If so, what is it? Cost? Thanks.
-David
-David
Well, now that I've heard everyone is getting the same BS, I'm even more pissed than I was before. $37,000, and they can't build the fu&king motor right. GM won't do anything, and they've got the dealerships reading right off the script.
Here's my idea.
Send an e mail to:
[email protected]
If they get enough of them, they'll listen. General Motors + consumer fraud = BIG STORY.
Send a letter to the EPA. (Defective engines getting 10MPG, burning oil) they'll have a field day.
Then, try:
60 Minutes
524 West 57th St.
New York, NY 10019
You seem to be on the right track, but a few dissatisfied customers obviously mean nothing to GM. When 60 minutes comes knocking at their door you can bet your [non-permissible content removed] they're going to start doing something about it, though.
BBB doesn't work, lemon laws don't work, let's see if bad publicity works.
Just got an e mail back from the folks at Dateline. Sent them the whole stiry. Apparently, the e mail adress is only for correspondence on show topics that have aired already. They DID say that if you have a story idea, send it to:
STORY SUGGESTIONS
Dateline NBC
30 Rockefeller Plaza
New York, NY 10112
The more letters they get, the better chance we ALL have. I'll tell them about MY experience with the dealerships and GM being less than helpful, but unless you guys do it too, it's really not a story. One guy with a bum truck? So what? But 10? 100? Now we're talking. Come on guys, what's one more letter? Who wants their truck fixed?
This is the only knocking cylinder which is approximately down 10 PSI on compression when compared with the average of the other cylinders. The engine knocks at all temperatures (although louder at cold start) and is now using approximately 1.2 qts per 2K miles of oil. Borescope inspections of the other non-knocking cylinders showed only the original factory machining.
I enjoy the board. I have found the truck I want...8.1L, 2WD, long bed, single wheel, BUT with 3.73. My '96 GMC with 4.10 gear 7.4L (290HP, 410 ft/lbs) pulls an 8500# travel trailer great. Any idea how to compare the ability of a 4.10 7.4L to a new 8.1L with a 3.73? Would I be getting as much towing ability (uphill towing grunt)? Thanks for the help
kip
BTW I got the 4.10 gears and avg 13.3 @70 mph and REAL BAD MPGs in town with my lead foot.
I just bought the chevy 2500HD long bed, 8.1L, crew cab I mentioned a couple of posts ago. Outstanding so far (after 2 days). I lost the directions to my Kelsey brake controller. It has 4 thick wires...red, white, blue, and black. Would anyone know where to connect these wires to the included brake wiring harness, which has a thick red and blue, and thin light blue, black, and brown wires. I am a novice at this kind of thing. Thanks for any help
Black is battery positive
White is battery negative (chasis ground)
Blue is connection to trailer brakes
These connect to factory harness (if you have) which are labeled on the harness. The brown wire (illumination) is not used, and if the trailer has a battery connection, the 40 amp fuse gets plugged into post #1 in electrical center under the hood.
The factory harness gets plugged into connection @ top left of the panel under dash at driver's left foot. There is a cover which needs to be removed to see. Remove plastic nut holding cover in place, connect harness & reinstall cover.
Hope this helps.
-Eric
Seeing as Anti-GM sites are on the endangered-species list 'round here....Come, join the carnage!
In my '96 7.4, 4.10, while going up a big hill while towing, I would downshift to "low 3" and the transmission would downshift 1 gear, and increase about 750 rpm. While test towing today with the Allison 8.1L, whether in tow-haul or not, if I downshift to "low 3" at the start of a big hill, going 70 mph, the tranny would downshift 1 gear, go up to about 3000 rpm, then every time, would after about 2 seconds, downshift again, and the rpm would increase to 4000 rpm...even though the extra downshift didn't appear to be needed to hold speed. Is the approved solution to always tow in overdrive, and put up with the searching for gears while going up an incline.... or drive in "low 3" and see 4000 rpm?
Thanks again.
kip
This brings up the question of what a warranty is for. GM is merrily handing out extended warranties to anyone with a knocking truck because they know that they can get away with not honoring them. (Just like they are not honoring the original warranty).
Would you buy a new GM truck knowing that there is a good chance that your engine will knock loudly and GM will tell you to take a hike when you attempt to get it fixed?
Go spam your own site some more.
Tom
Remember - this topic is about GM trucks - not Tundras. As painful as I know it is to own a knocker, can we please try to stay on topic?
- Tim
Piston Slap knock: Louder when engine/weather is cold and during lower RPMs. Then in some cases goes away. Non-detonation issue.
Carbon Knock: Louder when engine/weather is hot and during higher RPMs. Will not go away. Detonation issue. Higher-octane/slower burning fuel should solve.
Why then, Does GM refer to carbon build-up as a cold-start knocking issue in this TSB:
http://www.expage.com/gmtsbs
Just seems to be contradictive.
GM, I agree. In todays engines, with the taper of the piston tops and shorter skirts, some normal slapping will occur up to 1-2 or even 3 minutes in extreme cold weather. But those aluminum pistons should expand quickly and quiet down. (my 5.7 goes on for 15-25 minutes--most people agree that's not normal but GM says, "yes").
If the pistons don't seat quickly, excessive blow-by will cause higher than normal air-pressure in the oil pan causing oil to be blown up into the valve cover and down from the top where it is burned in the combustion chamber. Higher oil "usage" from higher reving, higher compression engines might be normal, but oil "burning" from blow-by is not.
Reference:
http://www.womanmotorist.com/MAINTENANCE/tomt/tt-enginesburnoil-01.shtml
kip
GM needs to address this problem. The sooner - the better for their long term viability as a car(or truck) manufacturer.
I know you're not stupid enough to think I said any of what you're "quoting" so just what is your purpose here?
You KNOW I'm closer to a Toyota brand loyalist than GM,but unlike you I'm not going to tell people your Tundra is actually a truck.Tundra is the only toyota I don't care for. I consider it to be Toyota's second failure in the full sized market.I also think they'll get it right on the third attempt.
change. Drive home. Drain oil. Start
motor..Let it idle....When it seizes.
Refill with oil...Call dealer !!!
You are under warranty right ?
I feel your pain I had 2 troublesome
toyotas, 1 pos vette, 1 pos T/A..
Dealers were NO help either.....
Had to bite the bullet on all of them !
But my last 4 GM trucks were great and
I snowplowed and worked em, to death !
Good luck......Geo
KG11, I think you're right. I just wish mine would go away in 2 minutes--it doesn't. Kind of a drag, my friend. I hear what you're saying. When it comes to slingin' the BS, GM is King.
Bama/KG, you know I really wish you guys could click (notice I didn't say, knock)--go out for a beer or something--doobie perhaps--little air-guitar. Life's too GD short. Love ya bro's.