My 2000 gmc sierra 2500 makes a funny squeaky sounding unph when I go from a stop

Maintenance/Repairs
1

This is about a 2000 gmc sierrra 2500 truck I purchased with 194k a few years ago. It now has 232k. Whenever I go from a complete stop, the noise sounds as if it comes from the rear area. It sort of has a sliding umph noise, as if a slide hammer is going from front to back with a resounding stop as I move forward. I have checked the driveline, the rearend, the bed attaching bolts, and most everything in the rear section for tightness.

I had the bed loaded heavily once and it seemed to not make the noise. When I tow a boat or tow nothing it makes this noise with a sort of bang or stopping sensation at the end like the slide of something that then stops. Who wants to ride under my truck for a diagnosis? ha ha

Like my ol’ friend Wayne Davenport from Alaska says… "don’t worry about it, when the #*@@$%# thing breaks you’ll know what to fix !! " he’s in his 70’s now and very old school and crotchety… so add that into your imaginary voice as you read his quote. He is quite right, so I’m just more curious than worried. He also gave me a running and driving shiny 1964 Plymouth Barracuda once, which I still have… so he’s awesome just to let you guys know!!

I own and maintain a virtual fleet of vehicles, with 4-66 chevelles, 1-1964 barracuda, 1-1969 dodge chinook, 2 chevy trucks of the 1970’s, the gmc pickup, and a 1987 pontiac fiero gt , and a couple motorcycles… not a stranger to fixing things.

Any ideas? Could it be in the transmission? ha, it could be anything we all know that !

thanks

2

The noise might be coming from the slip yoke of drive shaft where it’s inserted into the rear of the transmission. From a stop, the slip yoke can make a clunking, popping, snapping noise. The fix is to remove the driveshaft and lubricate the splines on the slip yoke with moly grease.

Tester

3

Hello Tester, and thanks for your comment. I did not mention this truck is a 4x4. Is there still a slip yoke at the rear of the transfer case?

thanks again

4

@sixty6chevy

Does this truck have a center support?

If it does, I’d check it. We have many GM trucks in our fleet, and the center supports seem to last about 50K or 60K

5

Hi i also own a 2000 gmc Sierra 2500 4X4 and i have the same noise.I had my mechanic check everything under the box to see what it was.It can’t be
the drive shatf or the gas tank because it would disconnect something.I once think that it could be the spare tire but that is very tight.If you found out what is causing that noise i would appreciate knowing because i will use my truck to drive to Florida next winter

6

I am thinking u-joint

7

A u-joint would make a noise when you touch the gas pedal ther would be a delay between the time you press on the gas and the time the vehicule starts moving
the noise i hear happens when i am increasing the speed.Like something would be loose in the box.Also when i brake i don’t hear this noise.It is only after i accelerate

8

How does your transmission fluid look? Bright red? Do not ignore transfer case fluid either. As a stupid fix change gas and air filter. Plugs ever been changed?

9

I have removed the spare tire and i has reduced the noise quite a lot.I now suspect the spare tire bracket

10

The spare seems tight, but I’ve never had it out. I will try that, but… hey does anyone want to buy a 2000 GMC SLT 2500 sierra ?? he he he! x cab and 4x4. $5k takes her !! :slight_smile:

11

Move the decimal point to the left one notch, and we’ll talk! :slight_smile:

12

oh yeah, I did just change the transfer case fluid with the AC delco blue fluid… somehow I don’t seem to be hearing the noise anymore. I will continue to test for it’s feeling and presence. As it was not just a noise, but a bang and something that could be felt. WOW, I hope that it’s fixed now :slight_smile: