Tranny acting up

[gargola1227]

I was Wondering if anyone could help me ? I own a 95 explorer xlt with the 4.0 motor Automatic . Well here goes i just recently replaced the motor in my truck and now somethings up with my tranny it seems to happen alot on the highway since thats all the driving I do . My truck shifts fine until it get to like 55 mph and then it starts to feel like if it want to either down shift or pick up over drive it goes from 2000 rpm's to like 2 1/2 3000 rpms and it does it like ever 2 minutes or so . Normally it would just stay at 2000 rpms at highway speeds also when i drive it slow it stay at 2000 rpms and you can fell the tranny changing but it doesn't seem to be picking up speed. please help me should i d be looking at a new tranny my truck has 113,000 mi on now

 

[Glacier991]

do you know if you have the 4R55 or the 4R44?

 

[TPLYNCH]

Your description sounds like what happens if your tourque converter is repeatedly locking/unlocking.

 

[Brain]

4R55E's went behind the 4L (4R44E's were reserved for the smaller engines).

Check the fluid level. Check for vacuum leaks. Is the Check engine light on? It does sound like a torque converter clutch locking and unlocking, and that is controlled by the computer which gets input from different sensors. The computer runs a solenoid valve in the tranny (called the TCC solenoid) and that valve could be malfunctioning also.

 

[gargola1227]

thanks guys. I honestly am new to this so I dont know what type of tranny i have .I do know that a few days ago for the first time my O/D light started flashing while i was on the highway . my check engine light only turns on if i'm doing a long highway trip other than that it never comes on . today is monday and the truck ran like a champ no problems what so ever . I'm confused ..... any info would be appreciated

 

[Brain]

In '95 they had the 4R55E, which is electronically controlled. The computer that determines the 'when and how hard' to the shifts gets its info from sensors. The CEL isn't definitely a tranny problem, but a blinking OD light is like a CEL for the tranny and could possibly be caused by whatever is causing the CEL to come on. Any idea on why the CEL would be on (have you 'read' the codes causing the CEL)? Those have to be fixed first before trying to diagnose the blinking OD light (which is like a 'check tranny light').