When I shift my truck from Park to Reverse after a cold start, I hear a clunking noise coming from the rear end that is similar to the clunk/click noise when I engage 4L.

I brought my truck into the dealership for a normal oil change and tire rotation, and asked the mechanic to check this out. He told me people have been coming in with similar problems. He said the fix is to simply pack the rear differential with grease. He said it is a 15 minute job with the truck already on the lift for the oil change. I wasn't charged anything for the work, but the noise has not gone away.

It sounds a lot like a solenoid clicking. Is this because the transmission is electric? Could this possibly be a U-joint issue? The noise only occurs after a cold start (being parked overnight or for a long time).

Has anyone else had this issue? Thanks for the input.

 

I'll throw this out there for thought. Might be dumb thought but could it be transfer case slop at output shaft?????? Mine does it a little at 112k mi....

 

Hundreds of posts on this issue

https://www.f150forum.com/f38/ford-s...everse-160965/

 

My truck did this clunk since new. 177k miles later, rear end blew out. Ford put a used one in that had 50k on it. No more clunk. It's so weird not hearing The clunk. I have about 1500 miles since the "new to me" rear end was put in.

 

Theres a TSB for it.... Just got mine from the dealer today to fix that issue under warranty