4-5 flare

[cooldrool]

1999 EXPLORER SPORT 5R55E 4.0 OHV.............ive had a thread about this problem a while back......but since its been awhile..id start anew...the 4-5 flare only happens when warmed up [20-30 minutes driving]....no other gears seem affected...reverse is good....ive had all the solenoids replaced as well as the VB gasket...imput and output speed sensors.....the pressure is a little low....so theres an internal leak....but where?.....reverse takes the most pressure and it works fine [so i dont think the pump].....ive beel told overdrive and possibly intermediate servo o rings leaking can do this......this isnt a common problem....and trying to find this scenario on all the Explorer/Ranger forums have come up NADA....can anybody help with this one?....thanks

 

[Fordzilla80]

Internal leaks are complicated to diagnose since you can't see them when the transmission is sealed. The low line pressure and issues only when warm could definitely cause a pressure leak since most seals expand when warm. That's about the only tip the transmission is gonna give you, aside from the 4-5 flare. Any number of seals can be leaking and causing your issue between 3rd and 3rd OD (4-5). It's really a guessing game of trial and error without doing a soft parts rebuild. What has been suggested to you already are good places to investigate, and you might want to check the o-ring on the corresponding shift solenoid, just in case it was installed wrong and the o-ring was torn, if applicable.

 

[cooldrool]

ok...thanks for the imput.......yesterday ..something new started to happen....it feels like the converter clutch is engaging or disengaging in 1-4 gears...it feels like its shifting twice as much as it should...but its not an actual shift.....all i can think is the converter clutch is doing it....very weird

 

[ranger7ltr]

Internal leaks are complicated to diagnose since you can't see them when the transmission is sealed. The low line pressure and issues only when warm could definitely cause a pressure leak since most seals expand when warm. That's about the only tip the transmission is gonna give you, aside from the 4-5 flare. Any number of seals can be leaking and causing your issue between 3rd and 3rd OD (4-5). It's really a guessing game of trial and error without doing a soft parts rebuild. What has been suggested to you already are good places to investigate, and you might want to check the o-ring on the corresponding shift solenoid, just in case it was installed wrong and the o-ring was torn, if applicable.

Actually 4th gear in the 5R55E is not 3rd OD; it is the forward clutch engaging...3rd is the intermediate band engaging on a drum and 5th is the od band engaging...If you are having a 4-5 shift flare I would replace the servos on the side of the tranny and see if that fixes the problem. The vb gakets and the solenoids leaking are also a possibility...

Also if you put the tranny in low gear do you have engine braking? If you don't or if the braking is slipping you could have the band not clamping tight enough on the drum...Of course the band adjustment might fix the problem as well...

Have you checked the band adjustments yet?

 

[cooldrool]

im trying to narrow it down....but band adjustments have come up in discussions too....related to servo problems.but i havent done it yet...............as you can tell...im trying to do everything i can to fix this without pulling and rebuilding the tranny...[its too much money for me right now].............im might do this my self probably........now...can anybody tell me if i can do servo work with the tranny in the rig?....thanks for any knowledge you have to give!

 

[cooldrool]

another servo thing.........ive heard of this servo pin bore problem where the the casing wears and the servo gets jammed...but im still thinking servo o-ring leak because of the low pressure symptoms

 

[ranger7ltr]

Servo replacement in the vehicle?

Can the servos be replaced in the vehicle? Sure it can be done...You will need to remove the center section of the exhaust from the y-pipe flange back to the tailpipe flange...Then you can use the Ford servo cover removal tool or use a wood dowel to pry the cover back to help you remove the snap ring and then remove the tool to remove the servo cover and servo...

Now the servo adjustment is meant to keep the band clamping force uniform when the servo is actuated...As the band wears the adjustment needs to be tightened up to keep the clearance uniform and to make sure the band engages quickly yet doesn't drag on the drum...

The servo pin can be a problem but it seems to be a problem on the newer 5R55N,5R55S, and the 5R55W transmissions which have bigger servo heads and pins that wear the pin bore...And remember the servo head has a built in seal to the servo cover and that is usually where the wear happens or the servo head itself being rubber will crack or become brittle and not seal to the cover...

 

[cooldrool]

excellent ....how much should i expect to pay for the servo tool?

 

[ranger7ltr]

Servo tool...

I bought mine for 30 bucks on ebay a while back...Or make one out of stock and half of a muffler clamp...

 

[drdoom]