Clunk in 1998 Chevy Taho

[tr00perg1rl]

Hey everyone,

My dad drives a 1998 chevy tahoe, the other day one his way home from work he was slowing down due to traffic and heard a loud clunk. He thought he was rearended it was so loud. I was under the truck earlier today check the U-joints and the transfer case fluid and the transmission fluid, and I can't seem to find anything wrong. I read somewhere that it may be the slip yoke but I have no idea what a slip yoke is and I can't find a decent diagram online. If anyone knows of a good site for this kind of information, or if you can help me figure this one out, I would really appreciated it.

Jess

[SpitAndDirt]

I don't know how much they have changed between the 97 and 98 years. I have a 96 Z71 and I am aware of the problem of the 4L60-E transmission shortcomings. You don't say how your Tahoe is driven, or if it is used for towing very often. Check out this other post I responded to: http://www.automotiveforums.com/vbul...d.php?t=273822 The clunk could be anything really from the transmission starting to go, to having a u-joint just start to fail. If the u-joints have never been serviced and you have over 135,000miles, it's not like it would be throwing money away. I would start there first. As for the tranny issue, the only thing I would recommend doing, would be to get a fluid and filter change done on it. There might even be a Technical Service Bullitin issued for the Tahoe also concerning the u-bolts that secure the rear axle to the leaf springs. Hope this gives you some ideas -Chris

[SpitAndDirt]

One other item, I do not believe you have a slip yoke on your Tahoe. I think the only vehicles that have them are larger trucks(2500,3500,etc). I don't even have one on my 96 Ext Cab Z71

[tr00perg1rl]

Originally Posted by SpitAndDirt

I You don't say how your Tahoe is driven, or if it is used for towing very often.

The tahoe has over200,000 miles on it and is used by my dad to commute to jerse everyday, about an hour from my home. It was used for towing but only a light trailer that held radio controlled airplanes. I checked the u-joints on it, the only place i found play in the drivetrain was where the front driveshaft goes into the transfer case (i hope im right on that explanation, im certainly not a car expert). i will take a look at the u-bolts holding the rear axle, i remember a problem with my trooper because those were not tight enough. thanks for your response.

Jess

[96tahoeguy]

i have a similar problem in my 96 tahoe. i found the info below on AF talking about someone elses tahoe and i'm passing it on. i would appreciate a follow up letting us know what you have found.

What you may be hearing is a driveshaft "clunk" that is caused by the slipyoke sticking to the output shaft.
The problem can be fixed with a new slipyoke from your GM dealer parts. it is a new design just for that concern.
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[Thunderbolt]

Originally Posted by tr00perg1rl

Hey everyone,

My dad drives a 1998 chevy tahoe, the other day one his way home from work he was slowing down due to traffic and heard a loud clunk. He thought he was rearended it was so loud. I was under the truck earlier today check the U-joints and the transfer case fluid and the transmission fluid, and I can't seem to find anything wrong. I read somewhere that it may be the slip yoke but I have no idea what a slip yoke is and I can't find a decent diagram online. If anyone knows of a good site for this kind of information, or if you can help me figure this one out, I would really appreciated it.

Jess

When he heard the clunk was it during or just after braking ?? Was it front rear ?? I just fixed a 99 tahoe that had a clunk when slowing down by braking or sometimes it wouldn't clunk until letting off the brake. It turned out to be the rear brakes were hanging up. I replaced the shoes and all the springs along with new drums since nobody was able to turn them at the time and the clunk was gone. I don't know about the Tahoe, But my 98 K1500 ext cab has a slip yoke on the rear drive shaft where it goes into the trans and I am sure the Tahoe does to. I would think that made more noise under a lad rather than slowing, But not sure.

[dduck1]

Ask your dealer for the service bulletin on Tahoe Driveline clunk.

Factory normal - do not attempt repair.

Had it on my 98, got it on my 02.

[MVu812]

Check this out...

http://www.automotiveforums.com/vbul...d.php?t=322890

[RainRider]

Originally Posted by 96tahoeguy

What you may be hearing is a driveshaft "clunk" that is caused by the slipyoke sticking to the output shaft.

My recent experience with taking my recently purchased 96 Tahoe to the dealer for this same clunk is in line with 96tahoeguy's response. The mechanic lubed the slip yoke - said it would need it about every 50k miles. It seemed to also get rid of some of vibration (from the road - rear end I would think) I was feeling. My thoughts were that if the driveshaft slip wasn't moving on the transmission output shaft, then the rear end movements would be coupled to the motor/transmission/mounts and I'd feel what was happening at the rear axle more.
I'll have to check out the new design yoke.
Anyway, just thoughts.
BTW, first post - great site, folks. :-)
Got a service manual on order.

RainRider (nickname from riding motorcycle - get caught in the rain a lot)