I have had my E4OD rebuilt on my 97 F250 Powerstroke. Ever since then, when it is warm, when I shift into reverse it lugs down like it is in a higher gear and backs up fairly fast, after a moment or two, it will feel like it downshifts again and reverses normally. Also, after a drive on the highway when I come off the ramp and stop at an intersection, again, it lugs down and wants to move forward, I have to apply the brake heavier, then it feels again like it downshifts to normal, then it will lug down again and try to move like it is in a higher gear. Once it is fairly warm, it will do this every time I stop at an intersection. I have taken it back to the shop on numerous occasions but they cannot find the issue. Any suggestions?
Thanks, Kevin

 

Sounds like your torque converter is not disengaging properly.

 

After the rebuild, (6 months ago) the first TC failed. This one was installed three days ago and it is still doing the same thing. What would cause it not to disengage?

 

Yea I agree first thought came to mind what Lead Head suggested.

First thing I'd look for is a short to ground someplace in the TCC lock up circuit. Something like that, an intermittent/varying short direct to "ground" causing the TCC to lock or partial lock when its not supposed to? could easily cause what you describe and would kill a TC pretty quick.

What its "temperature" has to do with it, happens warm but not cold be hard to say but that be first thing I'd check into.

If came to it install an OFF|AUTO|ON switch in that circuit as so I could turn it off verify that is exactly whats going on. If does verify that's what is happening switch also offers added benefit of manual operation/control until narrow down exact cause, save on the TCC retaining use of truck.

I don't have a diagram for a 97 Powerstroke so can't pin point wire color for ya.

 

purple wire w/ yellow tracer.

 

Oh ok yea same as gassers then, thought it probably would be but didn't want to assume as much.

 

Control circuit issue as mentioned could do it.

But judging by the fact that it's already eaten through a converter, I'd wager that the valve body is warped and is letting fluid bypass something. It is very easy to warp E4OD/4R100 valvebodies if you are not careful.

 

Thanks for your replies, Kevin