I’m not sure how long other than the last 2 months its been going on but my 2000 F350 has a weird pop or clunk noise that seems to be coming from the back half. I think when it first started I would only hear it when i was turning to get the truck lined up to back in the driveway, then it got to when i turned hard to the left id get it. Now it’s definitely more when I’m turning hard left but occasionally get it when turning right as well. Ive checked all my suspension bolts, flatbed mounts, exhaust where it could bump anything, rear driveshaft for play and probably a couple other things and have found nothing yet that would cause the noise. I don’t have sway bars so i know thats out, the only 2 things ive seen while under the truck are the leaf under the main one on the drivers side rear doesn’t have a wear pad unlike all the others so its metal on metal. The passenger rear body mount, while the rubber looks the same as all the others, on the metal portion attached to the frame it look like there is fresh rust similar to the leaf spring rubbing but no raw steel is visible.

Does anyone have a spot on the truck they think i should look at again or a different one that might be causing this annoying issue. While not detrimental to the truck, that i can find atleast, its getting really old fast and id much rather fix it before it becomes a big problem. It’s my daily so it cant be down for long but something definitely is up with it that id love to get resolved.

 

Did u change the rear diff fluid? If so, most require a friction modifier. When checking driveshaft play, how did the ujoints look? clean or greasy, any play at all.

 

Did you check the spare tire?

 

Have you lubed your driveshaft slip joint? (Usually clunks from stop to start, start to stop and not turning though...)
Slip joint regreasing

My aftermarket leaf springs clunk from time to time. Sort of drives me insane. You can get a prybar up between the main leaf packs and shackle and pry side to side to see if the leafs slide side to side from eachother. Mine do once in a while and it results in a pop/clunk noise. Felt mostly when turning into driveways with some incline to them.

 

Ive got a trutrac in the back axle, I was planning on popping the cover off to check everything out and putting new fluid in soon just to be safe. When I checked the rear u joints I had the rear end in the air and was pushing on the driveshaft at different angles and couldn’t get any movement other than the carrier moving some from the rubber itself. The joints looked good with only the excess grease pushed out or flung some. They’re 2.5 years or so old.
I don’t have a spare tire under the truck, or at all currently.
I greased the driveshaft 2.5 years ago I think so definitely wouldn’t hurt to do it again. I’ll have to try the pry bar in the leaf pack, it makes the noise when I get crossways in the road to back into the driveway most times but there isn’t a huge amount of slope. Last night I got a ton of popping noise but that was going over a large speed bump in a parking lot at an angle with both axles while turning.

 

Anyone have any other points worth checking out? Haven’t had a chance to mess with greasing anything yet, between work and holiday stuff I’ve been swamped.