08 Tahoe Vibration

[Doubeleive]

Update:

We replaced the front driveshaft with a Doorman replacement this morning and there was no change. The same vibration was still there.

After that, we swapped a different set of wheels and tires to rule those as being a potential issue and the issue persisted.

If we believe that the rear driveshaft/UV joints being the cause here, is there an efficient way to test this theory out in the garage?

no, best bet is junkyard drive shaft or order a new one, if you are lucky and a drive line shop manages to re-balance it right that might work I figure it's 50/50
you might not get it 100% no matter what.

 

[Traveler_ASF]

Hey Guys,

I have been chasing a vibration with no success that appeared out of no where in my 08 Tahoe LTZ and am coming to more intelligent minds than my own for suggestions/input.

Vehicle Details: 2008 Tahoe LTZ 4x4 with 165k miles (no lights on dash and no codes returned when scanned)

Symptoms:

• Vibration on both acceleration/deceleration (which prior to the first dealership visit was most noticeable above 77mph; it was observed at lower speeds as well ~40/45mph but at 77mph a passenger would identify that there was a vibration)
• Vibration is still present when putting the transmission into neutral at speed.
• Vibration is most noticeable on acceleration (for example; accelerate to 60, let off the gas, and the vibration is less on deceleration than it is upon acceleration).

I took it to the a local Chevrolet dealership for diagnosis and had their suggested work completed on it but the issue seemly is worse/more noticeable at lower speed than it was when I first took it in.

During this first visit to the dealership they:

• Replaced both Front Hub Bearings (technician noted that they were noisy and that the RF had play)
• Replaced A/C Belt (cracked)
• Total A/T Fluid Exchange
• Replaced Front Differential Pinion Seal
• Front Differential Service
• Front Differential Kit Service Synthetic
• Transfer Case Fluid Exchange
• Power Steering Kit Service

After that visit and noticing that the issue still existed, we took the service manager along for a drive on the highway and exhibited the same behavior as noted above. During this trip, it was observed that when power braking the truck that at least one of the engine mounts had failed.

During the second visit they:

• Replaced Both Engine Mounts
• Replaced Exhaust Manifold Gaskets and Bolts
• Replaced Exhaust Seals (2)
• Road Force Balanced All 4 Tires

Obviously a little defeated, I took it home after the second visit and wanted to rule out a tire issue (I believe this could be ruled out as the vibration subsides on deceleration) so I rotated the tires but there was no change in the symptoms after this. I checked for missing weights on both front and rear driveshafts and did not find any indication of any missing.

The truck was 99.9% of the time operated with the 4x4 selector in Auto but since having this vibration was switched to 2HI (and has been since before the first visit) in an attempt to rule out any complications there but the issue still existed. If I change the dial into Auto, I can hear the some engagement below the vehicle and nothing sounds bound up in the transition or anything.

It goes without saying that I am nearing my wits end on chasing down after already sinking a substantial amount of money into the fix. This truck has been solid with very little minor issues and shows that GM knew how to crank out quality even after a recession.

The only bad idea is no idea so shoot any ideas that you might have.

Appreciate any and all knowledge and experience for you guys! Thanks in advance!

I had a similar vibration, and took care of it by replacing the spindle on the serpentine belt. You may want to replace the spindle on the a/c belt as well. It was a low cost, low hassle remedy. The one difference was that my vibration was only on acceleration, not deceleration as well. Good luck!

 

[Fless]

I had a similar vibration, and took care of it by replacing the spindle on the serpentine belt. You may want to replace the spindle on the a/c belt as well. It was a low cost, low hassle remedy. The one difference was that my vibration was only on acceleration, not deceleration as well. Good luck!

Spindle? Do you mean the pulley? The idler pulley, or the tensioner pulley?

 

[08TahoeVibes]

Good Evening Guys,

Again, appreciate everyone's comments and knowledge transfers here.

We took the truck in for a PicoScope test was performed to further isolate the vibration. Which ended up pointing to the issue occurring in the rear of the vehicle.

- Advised to replace the U-Joints (Binding)
- Advised to replace the Slip Yoke (Leaking)
- Advised to replace the Rear Driveshaft (Rust)

There is evidence of the Slip Yoke leaking but have a few follow up questions for the group for input.

- Can anyone make sense as to why the U-Joints would be being replaced in tandem with replacing the Rear Driveshaft? To us, our research is showing that any "new" driveshaft that we purchase is also going to contain the accompanying U-Joints (they were when we completed the replacement of the Front Driveshaft).

I don't believe that have the tools/patience to replace the U-Joints ourselves but are not against replacing the Rear Driveshaft unless someone would advise against this. Our experience from replacing the Front Driveshaft showed us that we completed the repair in 30 minutes for $225 in parts when the dealer wanted nearly $800.

- Does anyone have any comments on replacing the Slip Yoke? To us, this says that we will need to replace the gasket/seal in order to stop the leaking.
- Is the Slip Yoke on the differential side (we believe so) or is this on the transfer case end?
- Does anyone know what all is involved in doing this? Is this as easy as removing the U-Joints, dropping the Rear Driveshaft, and pulling the Slip Yoke out?
- What are the indications that the yoke itself is needing replacement vs. just the gasket/seal?

Not against putting the money for the parts but if our experience in anything has shown, the recommended parts being advised to replace can be purchased new online for around $700 although the shop is asking $1,600 for the repairs. If we add the shops markup on the parts alone, we come to a relatively small labor cost number.

We are hopeful that this is a more educated guess than we had before and just not another education lesson of us learning everything that it's not.

 

[j91z28d1]

wow..


slip yoke is the end that goes in the tranny or transfer case if you have a awd. but same thing. seal just pry out with a screw driver and a hammer, tap new one in.

drive shaft comes with slip yoke, u joints, front and back installed already. please don't let anyone replace just the u joints. 95% chance even a good mechanic hammers on stuff hard enough to mess up the balance.


please order a new drive shaft and install it yourself along with a seal if you're seeing it wet at the front. if the back pinion flange is leaking that's a bit more of an issue. and since you've driven it a lot with the vibration, that's a definite possibility. you should not be able to feel any play at all in the rear pinion flange, the part the u joints go into. shake it up and down while you have it apart.

 

[j91z28d1]

1600$ to replace a drive shaft.


just feels like a crime.

 

[Traveler_ASF]

Spindle? Do you mean the pulley? The idler pulley, or the tensioner pulley?

Sorry — tensioner pulley

 

[08TahoeVibes]

j91z28d1 - thank you for the comments!

We have a new rear driveshaft and gasket ordered.

It will be a week or so for it to arrived and then probably another week before we can get around to installing.

Fingers crossed and will post with another update as soon as we have one.

 

[08TahoeVibes]

Bringing this hunt to an end here for anyone that might come across a similar issue in the future.

We replaced the rear driveshaft with a Doorman replacement last night and for now the vibration has completely went away. Once removed, the u-joint on the rear differential side was not moving smoothly and felt like it was binding up in certain movements. There was also substantial grime building up from what we believe to be the end of the slip yoke leaking out towards the rear of the vehicle (why didn't the dealership call this out during their multiple diagnosis - no idea). In the end of all of this, we would say that it is driving as good as it ever has now.

I would encourage anyone thinking of doing this themselves rather than paying the dealership. The dealership wanted $850 to replace (including 1/2 hour of labor at $200) while we were able to source the same part number that they were calling out (new) for $400 and maybe an hour of our time.

Use a jack stand to support the driveshaft after you get the joint of out the knuckle. Be prepared for some transfer case oil to get out once you remove the slip yoke out of the transfer case. We were prepared to replace the gasket on the transfer case side but after taking a deeper look last night, didn't find any indication that it was leaking, and we couldn't quite find a good way to remove the old gasket without destroying it so we left it as is for now.

Appreciate everyone's time and insight during this expensive experiment!

 

[Geotrash]

Bringing this hunt to an end here for anyone that might come across a similar issue in the future.

We replaced the rear driveshaft with a Doorman replacement last night and for now the vibration has completely went away. Once removed, the u-joint on the rear differential side was not moving smoothly and felt like it was binding up in certain movements. There was also substantial grime building up from what we believe to be the end of the slip yoke leaking out towards the rear of the vehicle (why didn't the dealership call this out during their multiple diagnosis - no idea). In the end of all of this, we would say that it is driving as good as it ever has now.

I would encourage anyone thinking of doing this themselves rather than paying the dealership. The dealership wanted $850 to replace (including 1/2 hour of labor at $200) while we were able to source the same part number that they were calling out (new) for $400 and maybe an hour of our time.

Use a jack stand to support the driveshaft after you get the joint of out the knuckle. Be prepared for some transfer case oil to get out once you remove the slip yoke out of the transfer case. We were prepared to replace the gasket on the transfer case side but after taking a deeper look last night, didn't find any indication that it was leaking, and we couldn't quite find a good way to remove the old gasket without destroying it so we left it as is for now.

Appreciate everyone's time and insight during this expensive experiment!

Thank you for following up and I'm glad it worked out for you!

I've come to expect that despite the money they charge, very, very few dealers are equipped or willing to take the time to do a proper diagnosis of anything. There's too much money to be made by prolonging the problem while throwing parts at it, at your expense. If you find a good one (and we have some competent dealer techs amongst our membership here), tell the world through good reviews because they deserve to be called out for their integrity and competence.