Brand New AT4X Making thumping noise in rear when backing out of driveway

AT4XMAN · Feb 2, 2023

So, Im far from a lifted truck expert. Just received vehicle. Seems to drive great on the road, but I cant help but notice a pretty noticeable thumping sound in the rear when going down the smallish curb of my driveway. Is this normal or should I take it to the dealership? Never had a lifted truck before.

gemarsh · Feb 2, 2023

A lifted truck should not make any other noises than a non-lifted truck.

BroCO · Feb 2, 2023

I've been fighting this for months. Mine turned out to be subpar aftermarket shocks in the rear, but in the process of isolating the issue I found the following that removed some of the other noises. 1. Check your ubolts for correct torque - mine were very loose. 2. Place some isolators (rubber) between the leaf springs - at the end of each leaf I made my own 'springthings' with 1/4" rubber as well as isolated the bottom leaf with some old bicycle tube. 3. Don't waste your time with a dealership. They'll only tell you the noise is normal and that is even more frustrating as they don’t try to find the source of the noise.

Good Luck! I know how annoying the clunk can be...

Teegunn · Feb 2, 2023

This is really odd. I have had my 2023 AT4X for almost a month now. Smoothest, nicest riding truck I have ever had by far. These new shocks on the AT4X and ZR2's are really nice.

I have had no funky clunking sounds or issues, and live in Montana where we have tons of snow and lots of big bumps on the crappy roads around here. Your issue is defenitely not something that should be happpening. Dealers can be a pain to deal with, you might need to be assertive in making sure they actually figure it out. Good luck, and let us know what you find out!

AT4XMAN · Feb 2, 2023

Thanks everyone for the replies. Going to take to the dealership next week. something isn't right.

Rockyah86 · Feb 2, 2023

Have an at4x and I had some clunking noise in rear also after a couple weeks. Tightened the u bolts at the leaf springs and it fixed the issue. They were not torqued very well.

Teegunn · Feb 2, 2023

Rockyah86 said:
Have an at4x and I had some clunking noise in rear also after a couple weeks. Tightened the u bolts at the leaf springs and it fixed the issue. They were not torqued very well.

Wow, that is kind of scary. If the u-bolts aren't torqued tight enough, what else isn't?

Glad you found the problem, and that it was an easy fix.