I have a 96 F150 with 4R70W trans. The problem is that it will not shift to 2nd till it reaches 4000rpm or I punch the accelerator. It will also race from 2000 to 3500 while on the freeway. The check engine light is on constant.

Thanks to all who reply

 

Well it feels like my standard response to problems with this transmission. Check the mlps they are cheap buy a new one and try it. If that doesn't fix it the roller clutch puked get a new trans.
Alan

 

My 2000 did a simalar thing but it was between 1st and 2nd when it done it with no check engine light on. I manualy shifted for a week until I could get to the dealership and trade the thing in.

 

A 2000 does not have the roller clutch a 96 has. I would guess you had a sticking solenoid or a bad/misadjusted mlps. I have worse luck with solenoid problems on the late solenoids over the early ones.
Alan

 

Alan,

I was able to replace the mlps, took it for a test. Seems that when I start out in jack rabbit mode, it gets to over 4000rpm before shifting. Although, when I do a nice smooth start, It shifts normally. Checked trans fluid level and it is in the correct range. The check engine light has turned off, but only after I decided to clean the battery post while I had the hood up. I'm looking for any other help prior to taking it in and having it decoded.

Mike

 

If the od light is not flashing I doubt you have codes. A conventional scanner can not pull those codes you need a rotunda tester to really find out anything. I would drop the pan and look for debris this sounds like the typical failing roller clutch symptoms. Until they completely break they work at light throttle usually.
Alan