GMC Sierra: Problems & Solutions

annfromdallas

Just bought a 2001 Z71 4 door with the 5.3 liter engine. I like everything about it EXCEPT a very irritating rattle in the driver's side rear door. It also emits a low growl from somewhere in the dash when you slightly press on the gas.
Neither one of these problems reared their ugly heads when I test drove the truck. However, they showed up after only 400 miles. Has anyone else had a similar experience?

jlflemmons

Yep, the rattle in the rear drivers door showed up at about 1500miles and the noise under the dash just this week at 6k. One noise I picked up on which may be your "low growl" under light application of throttle is the heat shroud on the muffler. For the door rattle, I found upon inspection that four of the retaining clips for the door panel are missing. Haven't found the dash rattle, yet.

annfromdallas

Thanks for the feedback. I'll take the information with me to the dealership and post my experience with the service department on the board. Should be interesting to see how they handle this.

jimkidd

I took my 99 Sierra in to the dealer for some warranty service and they insisted that the differential fluid should be replaced at a cost of $120. They said it should be done at the first 15k then every 30k after that. The owner's manual only says to check it every 7.5k and add if needed. When I mentioned to them that Jiffy Lube charges $24.99 to do this, I was told that JL couldn't be using the synthetic oil at this price and it would not hold up if I let them do it. Does anybody have any thoughts on this? Thanks.

hunter98

Use the Mobile 1 full synthetic I think it is 75w90 or 75w140. It costs about 1/5 or less the cost per quart. Take it to the dealer and pay for the service and not the oil. If it meets the GM grade, which it should, then you just saved $$$.

Hunter

jimkidd

Hunter, thanks for the advice. I am still curious why the owner's manual doesn't recommend doing this if it is really beneficial. In my 44 years of driving I think I have owned 16 vehicles and never even heard of doing this. Do you think it is really necessary. I don't mind the expense if it will save a repair later on, but don't want to waste money if it isn't necessary. Your opinion is appreciated.

jlflemmons

And it is a good one. The grab handle on the passengers side dash is attached internally above the air bag with some sort of slip-clip. If the clip is just a little bit loose it makes the durndest rattle you ever heard. To pinpoint if that is the rattle, very lightly bump the handle with the heel of your hand. If you get the rattle, Bingo. Now for the fun part. To access the latches, you must gently pull the A/C grill out and then the valve and duct behind it. No screws, just latches. Then you can reach the little latch and tap it and hear the same rattle. Push in on the handle and the latch should tighten up and voila! no more rattle.

By the way, since I didn't have time to leave my truck at the dealership to have the clips put in the door, I had to pay 20 cents apiece and do it myself. I told the parts manager that he owed me a car wash since I was not only doing their warranty work for them, I was even paying for the parts!

pgun2

I found what you were talking about. I pushed on the blue button, but that made the handle come off. How'd you tighten the handle bar so it didn't rattle anymore. I keep tightening it but then later it starts vibrating again. I keep having to reach over and push the bar in to stop it from driving me crazy. This is the one little rattle that gets to me. I've gotten spoiled now with the quiet ride. Any help is appreciated. BTW I'm in Austin (practically neighbors).

jlflemmons

So far, I found a 10mm bolt loose on the dash frame just above the air bag and on the back side of the dash, just below where the handle come through. I also found that the harness to the airbag was rattling on the metal shield around the air bag, so I wrapped a small piece of foam rubber around the harness being careful not to intefere with the airbag goodies. I take pride in my ability to fix these kinds of things, and this one is a doozy. On a road trip yesterday, I found that just by touching the grab bar the rattle would go away. Amazing.

Jim (in round rock)

sonofbob

My dad bought a 2000 GMC 2WD truck. It has a vibration that occurs around 50MPH. He was told by one service manager that it is a torque converter problem. The are unable to remedy the problem and say that it is not a safety issue they have no obligation to fix the problem. Has anyone had a similar problem or any ideas on where to point the service manager?

obyone

Is the vibration felt in the steering or the body of the truck. If it starts at 50, is anything happening at 40? Does the vibration disappear at higher speeds? If so, what speeds. Does the truck have General tires?

rrjung

I have a 2000 Ex Cab BB 1500 5.3L. At certain speeds (65-73mph) on some fays the truck "bounces", not vibrates. Only on the concrete parts of fays. I figure it's a relationship of truck length and fay expansion joint intervals. Have tried Edelbrock shocks, no improvement. When the bed is weighted down, there is improvement. My bed cover (not liner) actually improved the problem by about 25%. But, I still get very bad BOUNCING. ANY IDEAS !!

ryanbab

Its a truck not a lexus or bmw

I too notice the same thing on certain parts of the expressway where there are dips and such

The rear end is light unloaded so that has an effect like you stated you dont feel it as much when loaded.

I doubt there is or will ever be a fix for this. Honestly its something you have to deal with

Ryan

obyone

It is normal for the truck to do this because of its wheelbase and stiffer suspension. What I did was to add Velvet-ride shackels which softens the ride yet doesn't impact load carrying characteristics of the truck.

http://velvet-ride.com/index.html

costs about $200 and takes 15-20 minutes per shackel to install. Doesn't ride like a caddy but made an improvement similar to carrying a load all the time. Their website says may lower the rear of the truck by as much as 3". My truck lowered about 1" when measuring from ground to bottom of fenderwell.

cowboyjohn1

Could be out of balance tires or out of round tires. Check your tires for roundness, but be sure they are warmed up before you do. If they are not too far out, you can have them trued, but that is kind of a last resort as truing removes rubber from parts of the tire.
cowboyjohn

pojgmcscott

I have a 1999 ex. cab 4 wd, and after reading all these messages I didn't realize how many problems I really have. Yes it pulls to the right (2nd time), has a clunk in the column,and the 3rd door won't close when its cold,but here's the kicker. I keep cracking the frame on the rear sliding window (3rd one). All in less than 20,000 miles. Did I mention the rear main seal let go at 10,000 mi. ?. 5.3

obyone

sliding rear window was discontinued as an option due to it cracking. Cause was believed to be truck frame flexing.

pojgmcscott

Is there a cure for this flexing frame (which I had heard before).? Or, should I have the standard glass installed and possibly try to recoupe some cash. Like that will ever happen.

wnichols

Oh great. I just ordered an aftermarket slider from Harmon Glass and a bed cap w/boot and no front glass. Should I expect problems with this aftermarket glass as well? Maybe I should keep the original window just in case.

paintdude

http://www.geocities.com/crackeregg/00-02-35-004.html

Check out this sevice bullitin..

paintdude

I have the same problem with the truck pulling to the right...No service bullitens ,yet..I have some more info and phone numbers if you want to e-mail me..I believe it is the Steering pump, that is the problem...E-mail me at zrx@zrx1100.com ..

obyone

the aftermarket sliders are doing ok. Problems were from the sliders that came when ordered with the truck. So some blamed the slider and some blamed the truck. Who knows?

pojgmcscott

Just got done scrolling through the Silverado problems and you seem to be the man. One quick question, who are the BBB?.

tucsonjwt

the Edelbrocks mainly improve handling (less body lean in corners, and nosedive on quick stops.) The velvets will reduce the excessive, rapid bouncing on washboard roads, and will give you some improvement on the tarstrips on the highway, especially at higher speeds. I have bad roads in town around my house, and at lower speeds I still fell the bumps and tar strips, but I think a lot of that is due to cheap stock tires (P23575R16 Goodyear Wranglers). But like Ryan says, empty 1/2 ton pickups do bounce when unloaded. 3/4 tons bounce less, but you get a harsher ride in city driving. One odd side effect of velvets is that you get improved traction when starting out from a dead stop, like at a traffic light. It requires less accelerator pedal pressure to get moving, so you have a tendency to lay rubber until you get a lighter feel for the accelerator - surprised me when my V6 3.42 laid rubber on a normal takeoff One note, you may have to shave the bolt heads to avoid contact with the frame rails with the velvets because they have a "universal fit" style shackle - not a big deal but too bad they couldn't modify their design. I had a spring shop install mine for about $65 labor, as I recall. I am the kind of person who appreciates any improvement in ride quality, so $450 for the Edelbrock/Velvet combo installed was money well spent in my case - your results may vary. Good luck.

pojgmcscott

The Better Business Bureau ?

sonofbob

The vibration occurs between 40-50 mph. It is not noticable above or below those speeds. It can be felt in the steering wheel mostly but you can see your coffee bouncing about as well. My dad says that if you tap the brakes the problems stops immediately. That is why he believes it is in the torque converter. They have tried General tires on steel rims and Good year tires on aluminum rims. The district service manager admits that they cannot fix the problem but offers only an extended warranty in return. What good is that if your are not happy with your vehicle and dump it in a couple of years? We are filling out the BB paper work now as we feel it is a safety related problem. I just down loaded the service bulletin that someone posted about vibrations and will check to see if it applies. Thanks for the help!

obyone

There is also a tsb out for the driveline vibrations occuring at the speeds you describe. In GM's effort to attain higher mpg figures, the torque converter was set to lockup at approximately 38-40 mph. Your Dad is correct on this one. The reprogram helps some but not all. Did your dealer at least try this approach?

http://www.geocities.com/crackeregg/99-07-30-024.html

sonofbob

Hi Obyone,
The dealer said that based on his VIN that the service bulletin was complied with at the factory and so he did not reprogram the computer.

paintdude

2000 Z71,,My dealer has done the alignment and check the truck on the rack by increasing the rpms to 3000 to see if the steering wheel moves any on it own.. It didn`t...The truck just won`t follow the road effortlessly, like any other truck I have owned,98 Z71,96 ,94,etc...drifts to the right in 3 or 4 seconds..

I have spoken to one fella that said his was doing it and his dealer put a steering pump on it and it has seemed to fix the problem..

what do you think?

obyone

Yep, works for some and not for others. Actually the program allows for quicker downshifts rather than changing the shift points. So if you have the growl, depressing the pedal to downshift will eliminate this. Its not a solution, just a confirmation....also if you drive at 38-45 leave the truck in "3" or third gear and there should be no growl or vibration.

jlflemmons

I had to put the truck in the shop for an exhaust system problem (converter back to tailpipe has to be replaced) and told them to see if they could find the rattle and make it STAY fixed. Sure enough, they had seen it before. Took the airbag cover off and installed the missing bracket bolt that I couldn't see. Drove the truck all weekend, no rattle.
Also, instead of replacing the window for the air leak, they used a different screw on the frame by the latch. The wind noise is better, but not gone entirely. I have lots of warranty left on the vehicle, so I may give this one a little time and see if it is as good as it can be.
Oh, the pipe from the left bank converter has an OD 1/8" smaller than the pipe from the muffler it goes into. They cannot deform the pipe enough with a clamp to ensure a good seal, and since this is under the passengers compartment the whole thing will be replaced. Their decision, not mine, but I suspect that someone measured the pipe and determined it was not made correctly.

Jim

ed_b

Thanks for the link!

gvoigt

I've had my new 2000 MC Sierra Ex Cab BB 4x4 for just about a month. I saved a lot of money buying a 2000 instead of a 2001. Days away from it's first oil change and I have only two complaints so far. The rear doors are hard to close, especially when it is cold (below freezing)outside. I also get a rattle in the left rear door level with my left ear when driving. I think it is a cable the links the latch to the handle, which is tapping on the inside of the door panel. It is really bad when the door doesn't latch completely (note above).

My gas mileage has been anywhere from 12.7 to 16.8 depending on use. I have noted it does better on 90-93 octane verses 87-89 octane. I'd like to see better, so far I've only acquired 2200 miles. I would hope better performance after the first 5000.

I use my truck as a truck. I use it for work and I tow various types of trailers with it. Seems I am always hauling something for myself or somebody. I have yet to experience any of the steering issues I have read about, or heard any of the strange noises. But then again it is still a new truck.

Future plans are to add accessories that are functional and practical. Bed caps are already in place to be followed by a liner of some type. Then a headache rack to keep the cargo from damaging that beautiful back window.

ryanbab

Steering shaft problem doesnt show up till around 9K miles

jlflemmons

I just got back from the dealership after having the entire exhaust system replaced on my 2K 2500/6.0 EC. Only 7000 miles and a baffle let go in the muffler and the left side converter and header pipe were defective. For the first time I know what my truck really sounds like.

Jim

tomh12

Kind of nice,isn't it?

Tom

jlflemmons

and that weird rattle is gone, too...

whiplash0

My 1999 GMC SLT 1500 Extended Cab recently started making a noise after it was shut off. Investigation revealed a pump or motor was running under the truck beneath the driver's side door. The pump or motor stopped when the ABS fuse was removed. This was repaired by a Chevrolet dealer who advised they were familiar with this problem and it was minor. When the truck was repaired the bill was approximately $1700.00. Has anyone had this problem before? Thank you in advance.

jlflemmons

The location you describe for the pump is the location of the dynamic proportioning valve on the ABS. If they have very many of those pumps malfunction, we could see a recall as that valve has a major effect on braking under hard stop conditions.

ryanbab

When does the noise go away?

I have a noise that sounds like something is running kinda a high pitched hissing noise. It stops when i open the door.

ryanbab

oh also if i have the radio on just the radio after a few minutes itll start making this noise

stormyzkid

We purchased our 1995 Sierra new. About 2 years later we were having an intermitant problem after it warmed up a bit (15-20 minutes), the truck would stall when gas pedal was applied. Then it bucks a bit and flutters, almost like it is starved for gas. We had computer diagnostic done with no answers to the problem.
Again, this is intermitant.
If you let it cool down after a session of this, it does not seem to do it again for a while, maybe even as long as a few months.
It is quite a hazard when we are driving on the Interstate! We are looking for any TSB's on this.
I don't think the TSB's for the fuel Throttle linkage control is the same. This is more like
a fuel pump or fuel injection problem.
Anyone else with this situation? Thanks!

obyone

problem to me.

obiggs

The noise coming from the radio is a cooling fan, like the one's on your computer's microprocesser. It has a thermostat also

dansa2

dealer changed all 5 tires said it was bad lot. i also didnt rotate untill 10,000.my fault. but they replaced tires under tire warranty. asked me to bring truck in at 13,000 for a check. still shaking.so they rotated tires and balanced again. now at 15,000 still shaking. i have to give them srvice bulletin numbers someone posted earlier. let you all know what happens.

tanks

I just purchased my 1999 GMS Sierra a few weeks ago and started noticing problems within a week. The truck does pull to the left (but not always), it wanders quite a bit and requires lots of steering corrections, esp. when windy or on a uneven road. The service advisor says this is normal (JERK> BIGTIME!!!).
Is there anyway to test the steering box if it is defective??? Has anyone heard about any Technical Service Bulletins for this yet???
Does anybody else hear and feel a clunking from the steering on right hand turns> this is unfortunately hard to recreate when a service tech is taking it for a ride.
I also hear a growling coming from the front end when in four wheel drive.
The problems just keep adding up.

ryanbab

clunking in steering when turning right = NEW STEERING SHAFT

easy fix takes 30-45 min

Ryan

wxfcstr

Tanks: Your not alone!!! I was getting a groaning/clunking sound from 99 GMC Sierra 2WD when backing out of the driveway and once in awhile while making a sharp turn. My steering wheel would be turned right as well backing out of my driveway. The 1st miss diagnosis was dirty PS fluid. What a load of GM dog doo. I took it back just a few weeks ago to have the cracked rear slider replaced along with 2 recalls that showed up within 2 weeks of each other fixed and low and behold a different tech found the problem. The front cross member was loose. They tightened the bolts and the groan stopped. I will never buy a 1st year run vehicle again. Lesson learned.

jpfltaw

At least your service advisor did not use that " it's an optical illusion", B. S.

This wandering all over the road is scarry as hell in heavy wind on the hwy. Thats why I going to an attny. to document in the event I get wasted on the road.

ovalley

has there been anything more on the effectiveness of the early 2000 model frame bracing changes over the last several months on this site? Does the extra bracing help with the frame flexing feeling around 42 mph? Just thought I would ask the expert. Later.