2007 Jeep rear end rumble?

[MarksmanAkula]

Ive researched this alittle bit, but i wanted some input from the guys here.

Ive got a liberty that just got new tires, upper and lower rear end control arms, shocks, diff fluid, u-joints, the whole 9 yards. But i still get a rear end vibration at around 40-55MPH. I haven't tried highway speeds yet.

Im lead to believe its a bad torque converter. If it is, do i need to replace the whole transmission? Or just the converter itself?

Any help would be greatly appreciated!

 

[03GoingStrong]

Here's one discussion on here about it ... or something similar
https://www.jeepkj.com/threads/vibration-from-rear.55873/

EDIT: Use the forum search for RUMBLE. The cause could be torque converter, wheel imbalance, wheel bearings and maybe a few others, but the most common was a bad rear U-joint in the drive-shaft. I'd check transmission fluid too. Might not help anything but wouldn't hurt to check fluids and costs nothing ... unless it needs changing or added to.

 

[03GoingStrong]

... one other thought comes to mind ... was it doing it before you did the "whole 9 yards" on the rearend. If not, maybe it's something associated with those repairs.

 

[tommudd]

Several things it could be
tires are not always balanced correctly even at a """"" professional shop """"
Rear LCAs, were they tightened with full weight on them, not hanging down
U-Joints, make sure they are in the saddles correctly
have found all 3 to make or cause issues over the years

and as mentioned, when did it start ?

is it lifted or is it sagged below new stock height ?

 

[MarksmanAkula]

... one other thought comes to mind ... was it doing it before you did the "whole 9 yards" on the rearend. If not, maybe it's something associated with those repairs.

Yes it was. It did it right from the start, and I thought it was the tires on the back causing it. As they were 2 different sizes. So I got new tires, still vibrates when under speed.

 

[MarksmanAkula]

Several things it could be
tires are not always balanced correctly even at a """"" professional shop """"
Rear LCAs, were they tightened with full weight on them, not hanging down
U-Joints, make sure they are in the saddles correctly
have found all 3 to make or cause issues over the years

and as mentioned, when did it start ?

is it lifted or is it sagged below new stock height ?

not lifted, stock height. Yes everything was tightened down with full car weight, and as far as I know the tires are/were balanced.

what’s the thing with the U-joints though? I only replaced the one at the rear axle.

 

[tommudd]

replace the front as well
I've removed them with only 50-55,000 miles that were rusted and wouldn't hardly flex any at all
at least check it

you mention stock height, so you have had the suspension replaced ?
If not its sagged like Grandma was at 91

 

[MarksmanAkula]

replace the front as well
I've removed them with only 50-55,000 miles that were rusted and wouldn't hardly flex any at all
at least check it

you mention stock height, so you have had the suspension replaced ?
If not its sagged like Grandma was at 91

Where are the front U-joints? Coming off the transfer case I can only remeber there being one. Maybe I need to look again. EDIT - Yes there is a U-joint coming off the Tcase. Thats the only one i did not replace.

but as suspension related yes it’s all 90% new. Only thing that’s not new is front struts and rear springs.

 

[03GoingStrong]

How's the Liberty running? It's not a misfire at a certain RPM or anything causing shudder is it?
ALSO ... at speed and when it's doing it ... if you shift into neutral, does it stop the "rumble" or has no effect and it keeps rumbling?

 

[MarksmanAkula]

How's the Liberty running? It's not a misfire at a certain RPM or anything causing shudder is it?
ALSO ... at speed and when it's doing it ... if you shift into neutral, does it stop the "rumble" or has no effect and it keeps rumbling?

Runs perfect. Just replaced plugs and coils as it sat before i bought it. No misfire codes, no engine lights,etc.

As for the shifting into neutral, ive never tried that. it commonly happens around 35-45MPH and if you keep a consistent speed while its happening, it will keep going until you either speed up or slow down.

 

[tommudd]

coilovers on front
so all 4 springs and front shocks need done soon, may not be the problem but bet its bouncing off the bumpstops
I've had them come into my place with 75-80,000 miles and be 2 inches below new stock height and riding like a buckboard

what spark plugs?
and yes there is a front u-joint up right behind transfer case

 

[MarksmanAkula]

coilovers on front
so all 4 springs and front shocks need done soon, may not be the problem but bet its bouncing off the bumpstops
I've had them come into my place with 75-80,000 miles and be 2 inches below new stock height and riding like a buckboard

what spark plugs?
and yes there is a front u-joint up right behind transfer case

Plugs were NGK coppers. I know the engines dont like much else other than those.

Bounce isnt bad, but it does need to be addressed at some point.
Im 100% more concerned about the vibration over the ride quality

 

[03GoingStrong]

I'm no mechanic, just an old guy who's owned a few LOL ... and I've forgotten more than I now know HA. I just figured if it still does it at speed, while in neutral, that might make me think more along the lines of drive-line and rear end than transmission and torque converter.

 

[MarksmanAkula]

I'm no mechanic, just an old guy who's owned a few LOL ... and I've forgotten more than I now know HA. I just figured if it still does it at speed, while in neutral, that might make me think more along the lines of drive-line and rear end than transmission and torque converter.

Theres nothing wrong with forgetting stuff, you and the gentleman on this site have been extremely helpful with any questions i, or other members have.

I have a diagnostic appt with a transmission shop Thursday. Ill report back when i find out more.

 

[MarksmanAkula]

Theres nothing wrong with forgetting stuff, you and the gentleman on this site have been extremely helpful with any questions i, or other members have.

I have a diagnostic appt with a transmission shop Thursday. Ill report back when i find out more.

So transmission shop said everything transfer case/Transmission/Torque converter was all good. They did recommend that i rebuild the CV joints on the front driveshaft though. Said one was gone and that may be a big cause of the binding or vibrations i was feeling.

 

[Gyro]

The rear cv is the one that usually goes when the boot fails.
Link to rear cv rebuilt kit- https://www.driveshaftparts.com/index.php?route=product/product&path=174&product_id=978

Gyro

 

[MarksmanAkula]

The rear cv is the one that usually goes when the boot fails.
Link to rear cv rebuilt kit- https://www.driveshaftparts.com/index.php?route=product/product&path=174&product_id=978

Gyro

I popped the shaft off and the rear one was just dust. I ordered the link you sent me - https://www.driveshaftparts.com/ind...t_id=978&search=jeep+liberty&description=true