I am having trans problems with my 2002 V10 excursion. When in overdrive, the trans will rev up 300 rpm before down shifting into direct drive. It never varies in rpm always exactly 300 rpm. Its not slipping and it seems to be an electrical problem. Any thoughts ? It has 190k on it but has only been used as a family vehicle and has never towed. It has 50k on fluid change.

 

It does this out of the blue? Or when you give it more throttle?

Sounds like what happens when you push the OD lockout button, which could mean a chaffed or crushed wire in the steering column. Pull the cover off and take a close look at the small harness coming up from the shifter. Common for that to rub through and short out.

 

With that many miles I would just rebuild it. Auto trans only lasted 30-40k miles many years ago.

 

A rebuild for something that might be a free fix? Did someone hack Brent's account because that is way out of character!

 

After rebuilding automatics for 10 years I know that when they have a problem with that many miles 95% of the time a rebuild is the only answer.
Wanna bet?

 

Hopefully Mark K will chime in here.
If the event happens as you are increasing throttle position could it just be the torque convertor unlocking before the downshift that is causing the slight increase in RPMs? I'm not near my Ex currently or I would try to duplicate the situation and see what mine does before/as it downshifts.
I would troubleshoot this issue a good bit before diving directly into a rebuild.

 

Actually I would too but depending on how long you plan to keep it etc......all depends but usually they aren't worth fixing at that point. Too many parts, too hard to get at them.

 

300 RPM is about right for the torque converter unlocking.

 

Thanks for all your replies. I have owned a trucking company for almost 20 years so I have some idea. The trans isn't slipping. It seems to be an electrical problem to me . If I shove down on the gas pedal real slow it wont kick down until I shove darn near to the floor at times. If I am in OD and want to speed up just a little or even wiggle the pedal it will do this a lot , jump up in rpm , then drop back down to the original rpm and go like it should have in the first place. I put a small trailer and a mower behind and with that tension it never did it. Also if I take it out of OD it wont do it at all. It seems like it wont since line pressure or its electrical because it always jumps the same amount. I know some trans have went out way earlier than mine but this thing has never been worked in its life. It was handed down from my wife. Mark thanks for your input seems like you know a lot and you should with your back ground. You know this same trans has been used for pulling hot shot freight all over this country and have lasted this long. Yes I know I could just rebuild it but it isn't junk and its my families money. Dad doesn't get to spend money on himself when he has 4 kids and a wife to take care of.

 

Yeah, Mark is the tranny...I should say transmission guru around here. Wouldn't want to send the wrong message about Mark, HAHHAAHAH.

 

Did anyone else notice that he had 50K on the current flush?

Try changing the fluid using Mark's own method...my HD4R100 reminds me when I'm overdue on a fluid change with lazy shifts and other weird issues. A good fluid change and it's good to go again

 

Mark is a tranny?

 

Hey, it's only money, replace the transmission. Why bother trying to troubleshoot?