Mrmatt2009

finished my 3 inch lift + 1inch block last night and driving here to work this morning I was hearing grinding once and a while.. sounded like it was coming from the rear driver-side. I look and dont see anything rubbing... any ideas?

Gorillaxj

check your front backing plates to make sure they aren't rubbing or got teaked a bit, common that people bend them.

then it is "grinding" is it a rotational come and go? or a constant grind and then its gone? when turning? accelerating ect?

Mrmatt2009

What/where is the front backing plates, and it is not constant, doesnt seem to matter if turning accelerating or braking, it does kind of seem to when there is a bump or dip in the road, but not for everyone... its like it will do it off and on for 2 min then stop for 3 min and back. thanks for the help

Bustedback

Muffler rubbing on the driveshaft?

Mrmatt2009

good call, i will check when i leave work... really seems like its comming more from the other side though

jacked_xj

Mine does something similar. Only grinds once I let off... but goes away when accelerating

Mrmatt2009

I haven't driven it long enough to find a pattern ..... did u find out why its doing it?

jacked_xj

I'm thinkin its the driveshaft bein a little too short... but haven't confirmed I also want to try the tc drop first

no rdplz

Sounds like the rear driveshaft u-joints. U-joints get a wear pattern, and when you install a lift, the angle is increased, resulting in the joints "grinding" in a new pattern due to the different angle. This will actually destroy the joints. A t-case drop will help, is not fully resolve the issue. if you still get some noise after the tc drop, buy new u joints for the rear shaft and you should be good.

jacked_xj

So u joints and a tc drop will be the best bet for me?

Mrmatt2009

do I need to do ujoints too or just the tc drop

98CherokeeLimit4x4

Grab your rear drive shaft while in park and try to twist it and see if the u joint has play in it, If not its good , nothin wrong with replacing u joints though better safe than sorry.

Mrmatt2009

seems like the tc is the issue! is it worth it to change the u joints in addition to the tc? also when searching for tc lowering kits it seems like most are just over an inch... is this enough for 4 inches? difficult installation.? thanks all!!

ps is there just one u joint or two? are they different? thanks

no rdplz

jacked xj - yes, do both the drop and new u-joints.

Mrmatt2009 - Most tc drops are only 1". Very easy to install and it'll work perfectly fine for a 4" lift. I'd still replace the u-joints (2 of them, one at each end of the rear drive shaft, they're the same style u-joint) as they form a wear pattern and even with the tc drop will still wear out faster due to the new angle of the drive shaft. better to just do it all at one time and know it's good to go than to have a greater issue later.

ericfx1984

had the same issue... it went away when I installed a 1" t case drop