Rubbing / Grinding sensation in the driveline....

[Snagster123]

2020 PW: so after about 7 trips to 2 different dealers, STAR cases, etc.., they still can't diagnose. Rubbing / Grinding at slow speed like 0 to 4 mph then it goes away. This happens in forward and reverse, but not in neutral. Kinda tells me it's in the trans or maybe in the T-Case. I'm still under full drivetrain warranty, sooooo tired of this and soooo tired of taking it back to them...

Any ideas?

 

[ppine]

Change the lubricants in your front and rear diffs.
Check the U joints.

 

[Grey]

Brake pad sticking?

 

[Snagster123]

Change the lubricants in your front and rear diffs.
Check the U joints.

Already done by the dealer!

 

[Snagster123]

Brake pad sticking?

Dealer checked the brakes.. no issues!

 

[Snagster123]

Change the lubricants in your front and rear diffs.
Check the U joints.

Dealership did all that. I paid for a front end service (fluids), and they changed out the entire carrier assembly in the rear axle. Not the u-joints.

 

[Snagster123]

Brake pad sticking?

Dealer says no. But to be honest, it does sort of feel like a brake pad sticking... this truck has a lot of systems related to the brakes like Hill Decent, Hill Launch, antilock brakes, Adaptive Cruise Control, Collission Avoidance, etc... something in there could be messed up...

 

[Snagster123]

At this point, I am hanging my hat on either the Transmission or the Transfer Case. Pretty sure the Transmission has clutches in it. Does the Transfer Case have clutches or is it Gear or Chain driven?

 

[AMDPSU]

Going straight forward/backwards from a stop or turning?

Both my 19 and 22 Power Wagons had a vibration when turning from a stop.

Same run around from the dealer so I decided to change the rear diff fluid on the 22 to Amsoil at 17k miles.

No more vibration...

 

[2powerwagons]

Did you try turning off the hill start assist (or whatever they call it)?

I know it will make a chattering (for lack of a better term) when starting.
I leave it off, never use it..

On a different truck, dealer replaced the rear locker coil. Truck had a shudder when starting and turning. Kept taking it back. Eventually I talked them into checking the preload on the diff carrier bearings. Turns out they were set a little too tight.

 

[2powerwagons]

One other thing to check, the flex plate. They can develop cracks that propagate out from bolt holes and can make all kinds of strange noises.

It seemed common on GM trucks at one time and I've never really heard of it on Rams.

 

[Snagster123]

Did you try turning off the hill start assist (or whatever they call it)?

I know it will make a chattering (for lack of a better term) when starting.
I leave it off, never use it..

On a different truck, dealer replaced the rear locker coil. Truck had a shudder when starting and turning. Kept taking it back. Eventually I talked them into checking the preload on the diff carrier bearings. Turns out they were set a little too tight.

hill start.. turned off. They have replaced the entire rear carrier.. no change.

 

[Snagster123]

Going straight forward/backwards from a stop or turning?

Both my 19 and 22 Power Wagons had a vibration when turning from a stop.

Same run around from the dealer so I decided to change the rear diff fluid on the 22 to Amsoil at 17k miles.

No more vibration...

So these Power Wagons dont have clutches in the differential... they are gear driven positrak units... They have replaced the entire rear diff/carrier along with new fluid. they did add friction modifier which I dont understand adding for a unit without clutches. IDK...