5r55e troubles

[handyman1355]

I am currently having trouble with my reverse and drive they seem to engage but will not move till I raise the rpms, like there is not enough fluid pressure. I have replaced the valve body with a rebuilt one but still the same. I am going to replace reverse servo seals next. If that does not cure the problem I am considering rebuilding it my self. How will I know what parts to replace besides what comes in the rebuild kit?

 

[JK080]

How will I know what parts to replace besides what comes in the rebuild kit?

By ordering the parts after you disassemble the transmission and inspect every part.

 

[handyman1355]

By ordering the parts after you disassemble the transmission and inspect every part.

what do I look for say for instance if the pump was bad?

 

[JK080]

A worn pump should have grooves or scratches on the gears and in the body of the pump.

A line pressure gauge would help you determine where the problem may be. Are you sure that the filter is correct and the filter seals are good? Maybe overfill it by a quart or two, this can catch missing or leaking filter seal or low fluid due to incorrect dipstick (had that happen to me more than once)

What happened when the transmission first started to have problems? Was this something that happened all at once or this is how it is after some time of having other problems?

 

[handyman1355]

A worn pump should have grooves or scratches on the gears and in the body of the pump.

A line pressure gauge would help you determine where the problem may be. Are you sure that the filter is correct and the filter seals are good? Maybe overfill it by a quart or two, this can catch missing or leaking filter seal or low fluid due to incorrect dipstick (had that happen to me more than once)

What happened when the transmission first started to have problems? Was this something that happened all at once or this is how it is after some time of having other problems?

It started out going neutral after kicking passing gear in, evolved to going neutral in drive let up on gas it would go back in gear.I changed the separator plate gasket all was good. Strong engagement in all gears until I kicked it into passing gear again then I lost drive and reverse, but I can upshift manually from 1st and it will change into all forward gears after I get up to speed. reverse will engage but I must rev the engine for it to move, so I parked it so I would not cause anymore damage.

 

[JK080]

That sounds like a failed input sprag, it has to reapply in a forced 4-3 downshift and sometimes they break. When they break the condition will be no engagement in forward or reverse but will move in manual low and can manually shift up through the gears.

 

[corkey]

are there any mods done to you vehicle that you think may have caused the bad trans issues ?

bigger tires, hauling a big trailer ?

 

[handyman1355]

That sounds like a failed input sprag, it has to reapply in a forced 4-3 downshift and sometimes they break. When they break the condition will be no engagement in forward or reverse but will move in manual low and can manually shift up through the gears.

That's what I kinda thinkin too. Guess I may as well go ahead and put a rebuild kit in it as well. What do you think?

 

[handyman1355]

That sounds like a failed input sprag, it has to reapply in a forced 4-3 downshift and sometimes they break. When they break the condition will be no engagement in forward or reverse but will move in manual low and can manually shift up through the gears.

Question. You call it an input sprag, when I look for parts I see a overdrive sprag and a rear low sprag . Is there more than two sprags?

 

[JK080]

I call it the input sprag because that is really what it is, but it is referred to as the overdrive sprag by most parts people, I guess because its in the overdrive section. Ford calls is a one way clutch, which is what it does, it turns one way and locks the other.

The input "overdrive" sprag is not used (it overruns) in overdrive on this transmission.