My driveline clunks when I decel, then again when I accel. Front and rear u-joints have just been replaced, tps replaced.

1990 Ford F150, 300 I6, E40D, 4x4

Any help is appreciated.

 

Slip joint maybe?

 

Yea, i have that same problem. Can hear it mostly under 50mph.

 

I have the same problem. I had the U-joints replaced, the differential rebuilt, and it still made the same metallic clunk. Now they are saying the drive shaft has an inner and an outer part; apparently if the inner part develops a crack, it makes this clunk, both in forward and reverse. Only fix apparently is a new drive shaft; dealer suggested I live with it--apparently if this is the problem, it likely won't get worse.
Hope this helps--would appreciate any other opinions.
Frank.

 

I had the rear end and the drive axle examined again and was assured that there was not enough play to be causing my problem. After research, I replaced the TPS and reset the computer by disconnecting the negative battery cable. This solved the problem.

 

Can someone explain to me how a bad TPS could cause a clunk in the driveline?

 

From what I understand, a bad TPS can cause hard shifting and idling problems. In my case, the tranny was not "engaged" when I began to decel. When I would accel, the tranny would "engage" and cause the clunk (which was really the driveline catching up to the speed of the rear end. Anyway, I am not sure that is an accurate description, but the new TPS solved my problem.

 

Had the same problem but only when accelrating, greased the slip yoke and it solved the problem.

 

I have this problem as well, what is a TPS, how much is it, and how hard is it to replace?

 

TPS costs around $25 from parts store. It is really easy to replace, just two screws. You will need to disconnect the negative battery cable while you do the replacement. There is a way to check your TPS to see if it is bad or not. Search the internet, maybe even this site for instructions. You will need a volt meter to do the test. Good luck.

 

Radius arm bushings could make the noises you describe. I have the same noise and it's coming from those bushings. ...Terry

 

Hey, I have a 87 F150 with 276k. It has had this problem since I bought it at 30k. Every now and then this clunk, usually low in rpms, and sometimes a buck as if it shut off for a 1/2 second. I decided to clear out the bees and get it back in shape. I have all the easy stuff off the engine. My TPS screws were so tight I had to soak them in PB Blaster. I'm changing all the sensors that are hard to reach along with the vacum lines. It would be nice not to have that clunk and buck after it is all done. But if it gives me another 100k or so I won't complain.

 

Ive also had this problem, I always thought that this is how these trucks were, mine acts like a standard when you let off the gas and then get back on it. I will look into the TPS although mine idles and runs fine, but worth a try anyway.

 

My 89 had similar clunk, new spider gears tightend everything up and clunk went away.