I think before I sprayed some silicone spray around the rear leaf bushings and it seemed to maybe change the clunk, not cure. It's worse in the winter, agreed? Changing my shocks I believe cured mine mostly it also seems. It doesn't bother me anymore because I've checked everything over and it's secure so no more worries.

 

Yes mine is worse in the winter..

 

I have a 98 EB expy and I get the same sound.

I think I'm going to have to crawl under the back and see what gives. Mine is also worse in cold weather. It drives like a champ.. well it will when I get the new coil overs in, but i've never felt anything goofing up back there. I can only hope it's a suspension issue. Oh please oh please. Then the wife will have no choice, as some of you already mentioned!

 

I have the same issue. I am starting to think that it could possibly be a leaf spring bushing. Mine happens on both sides from the rear of the truck. It is a 99. Anyone ever swap them out with new ones?

 

Mine just started doing it, so a WD-40 bath of the leafs and gone. Just a heads up.

 

its just the original shocks on my truck doing it......same with the front, its common.

 

I've have the same issues and I've asked a mechanic and they said its 1) likely the pads between the leaf springs that need to be lubed or replaced. 2) Check the U-bolt torque holding the springs to the axle and 3) faulty rear trans mounts. Haven't had time to check any of this but let me know if one of you give it a try.

 

old thread but just for fun id throw in my 2 cents. i used to work for my local ford dealership and never was a real fan of fords. so as i pulled truck into my bay there was a speed bumpish type of thing that i had to hit crooked (one wheel at a time) and almost every truck that came through had this clunk. I was told it was the rear end and its normal for fords. so i put a truck up in the air and sure enough if you kick the tire hard enough its the axles sliding in and out. on light trucks like rangers (never tried on my 97 150) if you shake the crap out of it over the rear end you can hear it. i never thought about it after that until i got my first ford not to long ago. i just deal with it. i went over everything back there and made sure all was good and just called it a day. lemme know what you find

 

interesting....

 

i have a 98 f150 4x4 and it does it to i replaced leafe springs,had rear end apart and all looks good noticed that on cold days after setting over nite it woudnt clunk till it was warmed up someone told me to put high temp synthic grease on slip yoke that it was binding up havent done it yet as im getting used to the clunk.

 

Ford has a TSB for the "Clunk" when accelarating or going over bumps. It can be the slip yoke needs to be lubricated with teflon greese. I have performed this service about 5 times over the past 6 years on my 2003 with 130,000 miles and drive "Clunk" free!
This link provides a great "How To" with pics. http://www.eurekaboy.com/f250/slipjoint.htm

 

I have the same clunk too. I had the brake lines replaced today and the mechanic told me I had a broken spring hanger on the drivers side. He told me it was nothing serious.
I will get it fixed after the holidays.

 

gentlemen, ive found the thumping noise. I replaced my rear leaf springs on my harley edition. the springs were collapsed. i put a set of springs from a regular truck and added a set of 2 inch lowering shackles to bring the rear end down to facotory spec's. just like everyone here ive been trying to fix it for 2 1/2 years. finally down. i didnt put factory springs i used a set of aftermarket springs. i hope this helps everybody.'

harley2002

 

Does everyone have the factory exhaust system? I had the clunk noise in the rear when turning up a steep incline. I just put a dual exhaust in and noticed that my original exhaust had a bunch of scrapes And wear marks next to the leaf. So I think the noise comes from the t leaf hitting the exhaust