Rear end clunk/rattle

Hey guys, I’ve been trying to solve this for a while now and am at my wits end. 2001 Double cab, long travel with Currie rear end. Set up with Deavers and King bypasses. Automatic.

I’ve tightened every single bolt front to back and nothing is loose.

the noise is coming from what sounds like the rear of the cab. Metal on metal clunk especially over speed bumps, lot holes and rough roads. Rarely does it ever make noise over 45mph unless it’s a big bump or pot hole also.

I’m thinking cab mounts or bed mounts but I’ve checked both and tightened them all down. Could the bushing just be totally gone?

the clunk is loud and I cannot recreate its by jumping on the suspension. It’s similar to if you were to lift a wheel a few inches then drop off a ledge or curb, but somewhat metallic.

I’ve pressure washed the leafs and lubed everything possible and it affects nothing. Doesn’t matter if it’s cold or hot either.
Hallllpppppp

 

Update: sounds like a creaking wooden boat at times too.

 

Anybody?

 

slip yoke if its when you come to a stop and let off the break

 

I know you say it sounds like the back but check the R/L sway bar links. I had a similar issue and it was a lose sway bar link.
It was a more pronounced knocking sound when turning into an unleveled driveway.

 

Yeah I was gonna say driveshaft. Check your slip yoke and u joints.

 

No sway bar since I’m LT but I will check both the yoke and joints. Never even considered that but it would travel up into the cab like I mentioned.

it’s beyond annoying haha thanks guys

 

These things can look fine but in reality are shot. If they have never been replaced on the truck it's a good idea to do regardless if it's the problem or not. Cheap insurance- really. A good driveshaft shop charges >$100 parts and labor to replace u joints and regrease the slip yoke.

 

Greased all my u joints and yoke. Made a big difference on the initial shift from park to drive for sure. Smooth with no clunk. Funny I didn’t even notice that clunk much until it’s gone. That’s not the noise I’m trying to track down though.

It’s a rattle more than a clunk. Seriously sounds like it’s coming from the rear seat pans area. But I did find this..... see photos

it seems as though at some point I bent my leaf mounts and now the leafs are rubbing on the mounts. If the bushings are shot, which I assume they are if it’s moved that far over this is likely my vibration rattle.

Shook around everything I could locate and nothing is loose.