Transfer case clunk over bumps...? Loosing my mind! (2 Viewers)

[mattds]

For months I've been slowly tracking down a clunk that occurs when I drive over small bumps at faster speeds, from the middle of the truck. It's a 2016 with 55k...so not that old.

I've greased all slip yokes and u joints. (And ive changed the front diff mounts and almost all other bushings in the front). But I can feel some movement around the rear slip yoke or output shaft area from the transfer case.

I can't replicate the sharp movements of when the truck goes over small bumps...so how and what can I look or test for? (Ive read that I can take off a drive shaft possibly...and check to see if there is play?)

 

[Jstawgn]

You might over grease the driveshaft. Some of the grease are not compatible and harden when mixed.
When all the cavities are filled the driveshaft cannot compress when suspension cycles it hammer the transmission.

 

[mattds]

it's true i greased it with regular grease. Everyone keeps coming back to the slip yoke (perhaps for good reason). Does anyone now if it does any harm to remove one of the drive shafts? i'm thinking i would have to lock the centre diff maybe? thanks!

 

[jmanscotch]

it's true i greased it with regular grease. Everyone keeps coming back to the slip yoke (perhaps for good reason). Does anyone now if it does any harm to remove one of the drive shafts? i'm thinking i would have to lock the centre diff maybe? thanks!

You should be fine to remove one and test without locking the center. I did this when troubleshooting my Tacoma. Removed rear driveshaft it eliminated my vibrations, so kept it removed and drove 3 miles, in front wheel drive, to the driveshaft shop. Obviously, don't drive it that way more than you have to and take it easy on it, but unless the transfer case on the GX handles something completely different than the Tacoma, it will work.

 

[mattds]

You should be fine to remove one and test without locking the center. I did this when troubleshooting my Tacoma. Removed rear driveshaft it eliminated my vibrations, so kept it removed and drove 3 miles, in front wheel drive, to the driveshaft shop. Obviously, don't drive it that way more than you have to and take it easy on it, but unless the transfer case on the GX handles something completely different than the Tacoma, it will work.

The GX is permanantly awd...so i think i should be fine? (i mean i could lock the centre diff anyways...it won't bind if there is not a rear driveshaft)

 

[jmanscotch]

I’ve never done it with a full time 4WD vehicle so I can’t speak with certainty, but I don’t see how it’d be much different than a RWD vehicle placed in 4WD in the same scenario. The power split should still happen at the transfer case and offer power to the front axle and not just spin the rear output freely.

Personally, I’d try it without the diff lock first and if it works, then why lock the center diff?