Front Driveshaft Vibration

[AH64ID]

I would look for something in the transfercase.

Take the driveshaft out and run it on jack stand in 4H and see how the x-case output shaft looks.

 

[jdross440]

As I said in post 5, the alignment is good. All within specs. They checked the transfer case too, see post 9. I did talk to them a couple days ago and they are going to send the removed pinion yoke with the driveshaft to the balance shop so they can check it with and without it.
I wish I knew someone close that had a 2007-2008 truck like mine to swap their driveshaft into my truck for a test run. From what I have found, in 2009 they changed something on the driveshaft as the factory part number is different.

 

[AH64ID]

Have the axle shafts themselves been checked?

 

[AEdelheit]

As I said in post 5, the alignment is good. All within specs. They checked the transfer case too, see post 9. I did talk to them a couple days ago and they are going to send the removed pinion yoke with the driveshaft to the balance shop so they can check it with and without it.
I wish I knew someone close that had a 2007-2008 truck like mine to swap their driveshaft into my truck for a test run. From what I have found, in 2009 they changed something on the driveshaft as the factory part number is different.

Alignment within spec really does not mean much, unless you have actual numbers dont assume it is right.

 

[jdross440]

I have the sheet somewhere with all the numbers. The place I use tries to set everything to the middle of the factory specs. The vibration wasn't there before the gear change.

 

[lpennock]

I have the sheet somewhere with all the numbers. The place I use tries to set everything to the middle of the factory specs. The vibration wasn't there before the gear change.

Have they checked gear run out? If it wasn't there before the install and is there now and they have checked the drive shaft and the axles then the only thing left is the gears or the diff. Assuming they used the same diff it would have to be something with the gears. In theory it could also be a bad bearing on the pinion or carrier. Time to open it up and look.

 

[jdross440]

it has all new bearings and they used the existing differential. They did go back in and check the backlash and preloads. The gears is what I keep saying but for some reason no one wants to believe it. I even called AAM tech support and they didn't think so (they used AAM gears). I am going to call them Monday and ask again and ask them if they thought about putting the original front gears back in and run it on jack stands. I know that's a lot of labor, but if it proves it's in the gears they have something to go back to AAM on.

 

[AH64ID]

If the vibration has been there for 70K miles and you just did the gear swap I don't see how it can be the gears.

The increase in driveshaft rpm from the gear swap may be why there is a different feel, but it doesn't sound like gears based on your description of the timeline.

Have you checked the front DRW adapters to see if they are still true?

Axle shafts?

Assuming you have stock tires, and based on the info in post 1, it sounds like the vibration is felt with the front driveshaft spinning between 2200 and 3000 rpms. That would change to 50-68 mph for the vib. Is that what it shifted to?

 

[User113]

Assuming you have stock tires, and based on the info in post 1, it sounds like the vibration is felt with the front driveshaft spinning between 2200 and 3000 rpms. That would change to 50-68 mph for the vib. Is that what it shifted to?

That's a good point, if the speed at which the vibrations start has not changed, then the imbalance is between the ring gear and the wheels. On the other hand, if the speed at which the vibrations start has changed, the vibration is caused by something between the pinion gear and the transfer case.

 

[jdross440]

The vibration I was feeling before was minimal. Could feel it slightly in passenger seat. The wife doesn't even remember feeling it. She said it was just me. I went back yesterday (they had gotten the DS back from the balance shop again-they did move some weights around). They put it in and no change in vibration. It starts right at 55 mph but isn't an increasing vibration. When it starts it shakes bad. I have to take it back next Tuesday and they are going to go back into it and see what they can find inside. The tech from AAM called me yesterday while I was there. He has been running it by all the others there including the shop people. They are at a loss, but are still going to see if they can come up with something also.
I am taking it to the alignment shop Thursday to have them recheck everything.

 

[sag2]

You really need to find a dealer or shop with a vibration analyzer. Sounds like your guys are lost. It doesn't make sense to keep balancing the shafts and think your going to get a different result. I don't want to go though it all over gain, so if you do a couple searches you should be able to find several posts from the past where I went into great detail on diagnosing the 62mph vibrations that plagued the quad cab short box trucks. Diagnosing your truck properly can be done using the same procedures.

 

[ro23j]

I took my 2006 to the dealer for replacement of a leaking front axle pinion seal. On the drive home, it had a vibration similar to the one you described. The dealer told me to bring it back and they had it for two days diagnosing the vibration. They tried removing and re-indexing the driveshaft several times with no improvement. The vibration stopped when they replaced the yoke. They did not say how the yoke got damaged but it obviously was when it was removed to replace the oil seal. I hope this helps.

 

[Motorhead]

This may be far fetched but... Would it be possible to remove the REAR drive shaft, put a oil leak sleeve in the rear output so you don't lose the transfer case oil, put the transfer case in 4 high and drive the truck with the front drive only and see if the vibration is still there.

 

[jdross440]

They put the truck on jack stands and put the drive shaft back in. When they ran it they saw wobble at the pinion yoke. They took the front differential back apart and found that the 2 new pinion bearings were bad (and these came in an install kit from AAM). Said they had some notches in some of the bearings rollers. So they replaced them along with the crush sleeve. Put it back together and no vibration. I had asked them 2 or 3 times if they were sure it wasn't something in those bearings or the pinion itself. They said this is the first time they have had this happen-vibration after changing gears. The driveshaft shop said it did need balancing and that on these where they ujoints are put in with the epoxy they need balancing after changing for some reason.

 

[lpennock]

Glad you have it solved.

 

[ssanders60]

My 2003 had the same vibration, it was in the CV joint, I notice below that some one called it the cardon joint, I bought a new drive shaft
and cured my vibration problem, $620 was the cost. It always had some vibration at 70 mph, drove it for 92,000 miles before it got so bad
you could not drive it. you could see that the cv joint was hanging up when you turned it by hand. Something is happening with that ball.