So just recently my truck has begun to run awful after I tow a load. This weekend, I towed a 24' boat for only about an hour. During that hour that I was towing, the truck ran awesome, as it always does when I tow something. After I unhooked the boat, then truck ran terrible. The engine surged, and the tranny slipped between gears and it just flat out ran terrible. I got into the truck this morning, and fired it up and it ran great. It has ran great all day long. It seems to only do this right after I tow something. While I was towing, I used the 60 tow tune on my dp-tuner, and I always use it when I tow. Does anyone have any idea what might be wrong?

 

just giving myself a bump...

 

how hot was your trans getting, could be that it is getting to hot and then after slipping.

 

it was only running around 180 degrees.

 

Did it throw any codes ?

 

What tune did you switch back to after unhooking? If you went up in power to the 80 or 140, it might be old or dirty oil causing your IPR to do funny things. You could try leaving it in the tow tune and see if it does the same. Don't know, just throwing out thoughts.

 

That's your truck's way of telling you "let me tow, I wanna work!"
Honestly, I have no idea. Maybe when you unplug the trailer lights its messing with your electrical system somehow???

 

Could it have been the PCM learned the caracteristics of towing, fuel, load, and then its trying to learn it again without a load, just throwing things out there. After my 568 mile trip home from RRE, my truck ran a little rough, not enough for anybody else to know but I could. Smoothed out after driving it a while. Didn't think it was a major issue.

 

I switched back up to 80E. I just can't figure out why it ran fine the next morning. Maybe I should just leave a load on it all the time haha. The oil should be fine, it is only at 4000 milies. My main concern is that it may be the tranny. Does anyone know if this might be the case? The only reason I ruled the tranny out was because the truck pulled fine with a load.

 

How about a tranny flush and fill, maybe drop your pan and see whats in there. I was telling Barry before I got the J-W VB, I was noticing some slipping, just a couple times and I did a fluid change and installed the VB, no more sporatic slips .

 

No, it couldn't be that because the 7.3L PCM isn't capable of learning any of that.

 

I'm gonna get the tranny flushed next week, and see if that helps anything.

 

01 might have a diode that is causing problems or starting to cause problems.

 

I am the second owner of the truck, and the guy I bought it from had the tranny replaced at 65000 miles. Could the dealership have put in a new tranny with the diode problem?

 

Not a dealership since they get reman units and those wouldn't have the diode.