'99 3.0L w/4R44E - trans won't lock in R at all times

[nxne75]

This site is a great resource - glad I found it. My situation:

I've got a 1999 Ranger XLT, 3.0L with the 4R44E automatic. When I shift into R, sometimes the transmission won't lock up. If I give it enough gas, it will lock up but it makes a loud "CLUNK" sound before it locks up. Alternatively, if it won't lock up in reverse, I can sometimes put it in drive, then put it back in reverse and it will lock up correctly.

Any thoughts/ideas on why it's been doing this? It's been an ongoing thing for several years now - just a mild annoyance on what's otherwise been the best vehicle I have ever owned.

Thanks in advance,

Keith

 

[Bruce]

How does the transmission shift going forwards?? The 2 things applied in reverse are the direct clutch and reverse band. If third gear is kinda slipping then either the clutches are bad or it could be the sealing ring in the center support are worn or hard. If you have a good third gear then i would say probly the servo seals have gottin hard and not sealing or could be EPC not giving enough pressure to apply all things to make reverse work.

 

[nxne75]

I'm going to assume here that by third gear you mean Drive, so...

In drive, with the truck moving, the transmission works fine, although...every once in a while, the transmission (at least I think it's the trans) will sort of "clunk" forward while the truck is moving. I had one other person say they thought that clunk might be u-joints, which I suppose could be a possibility? The truck has 160k and I have never changed the u-joints.