I just a new- used 4r70w automatic w/od in my truck had 103,000 miles on it. No slipping in reverse or 1-3rd gear but slips when engaging into od. But if i let off the gas pedal then reapply its then engaged and goes fine in od. What can this possibly be.

 

Are you sure it's not just the torque converter? The TC doesn't mechanically lock up immediately when you first start driving.

 

Honestly im not sure. My obd2 plug doeant have power to it so i cant even get it diagnosed until i sorth that issue out. It diesnt slip in any other gear only when its engaging into over drive but once it engages it no longer slips.

 

Check the cigarette lighter fuse.

 

Ill have to look in to it. There is two lighter outlets side by side is there a chance that they work off 2 different fuses bc i know one works forsure bc i use my car charger in it.

 

Check the manual for fuse locations.

http://www.fordservicecontent.com/Fo.../98f12og1e.pdf

 

Okay thanks i just did and it appears that one is powered by auxiliary power plug fuse and the other is operated off the cigarette lighter fuse. Ill check the lighter fuse in the morning when i leave for work.

 

Overdrive won't engage before 45 mph.
The trans must be up to temperature before OD will engage.
Are you sure you are meeting these parameters?
Also the TPS has control over when the shifts occur.
Running in OD then sudden lifting of throttle can unlock the converter for a few seconds then re locks again. Its normal.
You don't offer very much to what's happening.
A trans fault usually will flash or light the OD shifter light.
Nothing to do with the OBDII port power unless your looking for codes with a Scanner.
Good luck..

 

This one is shifting into over drive around 35mph. The light on the shifter for over drive does work however its not flashing at all and it doesnt come on unless i turn od off. Yeah i was trying to get power to obd2 connector so i could scan codes bc check engine light is on. I finally got it working the manual said it was fuse #12 so i took face off the fuse box and there were no prongs inserted to connect the fuse to the prongs in the bottom. I add to inserts and now the connector has powet however since i had the power unhooked while doing this the light is no longer on so now ill have to drive it for a while after i get off work until the light comes back on then ill have it scanned and see what comes up.