Ok here's the situation. My E4OD recently appears to have started slipping in 4th gear. Normally, upon initial startup and driving, the converter would never lock up in 4th gear until the tranny got warmed up some (which I've heard is normal for these trucks). And after a short amount of driving (depending on outside temperature) the converter locks up and everything is fine. But now, shortly after the previously mentioned routine takes place, the tranny appears to be unlocked in 4th gear only when trying to accelerate. Yet while just cruising in 4th gear the rpms are low as if the converter is locked up. Under light or moderate acceleration the rpms will climb easily like its unlocked, but it isn't as loose as when it's 'officially' unlocked upon warmup. It has the 'feeling' of being in the middle of the locked and unlocked status. It's almost as if the 4th gear clutches are slipping or something? Any suggestions from the tranny experts?

 

If it is slipping the fluid will be black in a couple miles. Is it black?

 

Mark will take care of you and I would say its slipping and time for a rebuild. WAG

 

I will check tomorrow to see if the fluid looks black or smells burnt. It was fine a few months ago when this started and the truck don't see much use but I'll check it again.

I know the torque converter hasn't been able to handle the increased power under hard acceleration for a long time now, but driving normally it always worked ok. I'm planning a BTS tranny in my future but just trying to figure out right now what the issue may be and possibly determine if its electrical related or strictly mechanical. The overdive light on the shifter is not flashing.

 

does your truck buck like your on a rough road in 4th at low rpm. say 45-50 mph? i'm having a similar issue with my stock '95, only i can not blame increased power yet. however the trans fluid is clean in mine.

 

Bucking at low RPM in fourth gear is usually an engine misfire.

 

That may be a new topic later then. Thanks for the info. Still learning about this diesel stuff. And fear of the auto is not helping

 

Fear of the auto?? I burned up three of them and finally spent the big bucks on a John Woods.

 

Yeah i dont understand the autos and i know i can not fix them. So i am afraid to break one and when this thing starts bucking like what i thought was a slipping clutch in od i get scared. Honestly when it needs a rebuild ill swap a 5 speed. But i really do not want to do that yet. Still fixing leaks and stuff the po just left alone. But if it is a misfire then ill start checking on that. Could it be low fuel pressure?.

 

Alright guys just got back from putting some miles on and getting the diesel all warmed up today in this 0 degree weather. I checked the fluid and it's at the proper fill level at idle and the fluid is pinkish/red. It does not look black-like or smell burnt. I would say there are several hundred miles on the truck since this symptom started happenning, so I would assume if clutches were slipping it'd be apparant with blackish fluid by now.

I think what's happening must be the converter unlocking in overdrive after it gets up to temperature for some reason. Any other causes for this symtom? Or suggestions what may be wrong? I believe the lockup solenoid is working as the converter will lock up in the beginning but then after some driving it's like its not locked up anymore, hence my issue.

Also, I believe I may have mis-spoke in my initial post when I said it felt like it was in the middle of being locked and unlocked. When I was referring to the converter being 'loose,' I was thinking of how the rpms are up when in 3rd gear with the overdrive turned off.

 

No I have no issues like that. I would agree more with the previous posts that it sounds like you have more of an engine issue.

 

What you might consider doing is putting a TC lock swithch on. That way if you feel that's its unlocked you could flip the switch and see if it makes any difference. There was just a thread going on talking about it and it had the directions on how to do it.

https://www.ford-trucks.com/forums/1...ck-up-mod.html

 

I was considering doing this for testing with this issue and I think I may just rig up something and see if it makes any difference.

If it does lock up with this mod then what would be causing it to unlock under normal circumstances? I've heard burnt out brake lights may cause a torque converter to not lock up at all but I checked my 3 brake lights and they all work fine.

 

I had this problem last summer and had to drive it a couple thousand miles pulling my 16k 5er. I started this thread, maybe you can find a few things in it to help you.

https://www.ford-trucks.com/forums/1182062-tc-lock.html

 

Hey thanks for the link I did find a few useful points to look into.