5R55S upshift to too high of a gear

[NHarris]

I have an 05 Explorer 77K miles and I'm noticing that lately (since it has gotten worse) it upshifts to a high gear especially when the transmission is under load. Going uphill at 30 mph I should be around 2000 rpms (2nd gear) and it will shift into 3rd then quickly drop to 4th gear throwing my rpms down to a little over 1000 rpm. Also it seems to have to search for a proper gear. Like it will kick (not a smooth shift) into 4th from 2nd, then shift back to 3rd.

Any ideas what is going on?


-Nate

 

[sethmorgan]

I can't help you but I'll give you a bump since my '02 5R55W does something similar.

Under light throttle it's like it shifts into OD too soon. I describe it kind of "flopping" into gear. It started after the tranny was rebuilt a while back. The shop said there was nothing wrong mechanically and that since the shifting was controlled by the computer, there's nothing to be done about it. I've since exhausted all computer-related solutions (flash PCM with latest transmission update at dealer, adjust for different axle ration in computer, SCT tune) and am now thinking it is indeed mechanical. I've just been living with it this way but would like to find a solution.

 

[NHarris]

I have to get my tranny replaced in a year or so, so its nothing to worry about (for me). I'd like to find out what exactly it is though.

 

[sethmorgan]

I hope you don't have the same experience I did.

 

[NHarris]

I've always wondered if its dealing with the servo bores...