Tranny Rebuild

[Bekoatvb]

Just rebuilt 2006 Exp tranny. 5R55S. Babied this thing for over a year with no reverse. Finally down to only 1st gear.
Replaced: all bands, clutches - seals - o-rings - servo pistons. Remanufactured pump. Reverse drum assembly - band - servo piston. New valve body - shift solenoid pack

• Now have 3rd - 2nd - 1st gear
• No "D" gear
• Reverse reacts "just as it did" before rebuild. Can feel it shift in, tries to move a little, acceleration doesn't help. All reverse components new, don't want to damage anything

Any ideas to what I can do. Going to keep picking at this thing. Plan to pull it back out if needed. It is now a vision quest. All advice/ideas welcome.
Asking: Could this be the torque converter? Could it be the housing wear for the servo pins?

 

[Rick]

I'm not sure if this will help, but there is a discussion about no drive in this thread about the 5r55E.

5R55E no drive

Hi everyone I'm new here, I was hoping someone here could give me some ideas about what could be causing my trans to have no drive. Its a 5r55e out of a 98 ranger with 4wd the motor is the 4.0L v6. I had a local trans shop rebuild it back in January because of the same problem. First second and...

www.explorerforum.com

 

[Bekoatvb]

I'm not sure if this will help, but there is a discussion about no drive in this thread about the 5r55E.

5R55E no drive

Hi everyone I'm new here, I was hoping someone here could give me some ideas about what could be causing my trans to have no drive. Its a 5r55e out of a 98 ranger with 4wd the motor is the 4.0L v6. I had a local trans shop rebuild it back in January because of the same problem. First second and...

www.explorerforum.com

Thanks Rick, everything helps. I'm reading anything I can. Double checked the reverse servo, band and drum last night. Actuated the band manually and turned the drive shaft, the band held the drum as it should. Going to pull the transfer case next, disassemble .

 

[JK080]

If this transmission wont go into reverse or drive and only moves forward when the OD is canceled or manual 2nd or low is selected the number one cause of this is a failed input sprag. This sprag can wear out or flip over and "look" fine especially if your not familiar with the way it supposed to look or work.

I can promise you it's not your transfer case or the torque converter they have no idea what gear you have selected so they won't just only work in the manual selections.

Worn servo bore symptoms are shift flares mostly during the 2-3 and 3-4 shifts not forward and reverse engagement issues.

Unfortunately you will need to pull the transmission back out and remove and inspect the input clutch/sprag assembly. If the sprag has just flipped there is a good chance that the inner and outer sprag races are damaged so you may be replacing all three pieces so look closely.

Check out this post for more information

 

[Bekoatvb]

If this transmission wont go into reverse or drive and only moves forward when the OD is canceled or manual 2nd or low is selected the number one cause of this is a failed input sprag. This sprag can wear out or flip over and "look" fine especially if your not familiar with the way it supposed to look or work.

I can promise you it's not your transfer case or the torque converter they have no idea what gear you have selected so they won't just only work in the manual selections.

Worn servo bore symptoms are shift flares mostly during the 2-3 and 3-4 shifts not forward and reverse engagement issues.

Unfortunately you will need to pull the transmission back out and remove and inspect the input clutch/sprag assembly. If the sprag has just flipped there is a good chance that the inner and outer sprag races are damaged so you may be replacing all three pieces so look closely.

Check out this post for more information

I can feel it engage into reverse, the vehicle will move a little then when I accelerate it slips and barely moves. The strange thing is if I "hit" the gas quickly it will move backwards for just that moment of quick throttle. Repeated this about 6-8 times then decided to quit. I already pulled the transfer case and disassembled it. No obvious issues. The fluid was probably original (220,000 miles). Going to put new clucth kit in since it's already torn down. Since I have the transfer case out, I'm going with your information and pull the tranny and check the clutch/sprag assembly. I was debating on this anyway. Thanks for the info. Will update as soon as I get that far.

 

[Bekoatvb]

I can feel it engage into reverse, the vehicle will move a little then when I accelerate it slips and barely moves. The strange thing is if I "hit" the gas quickly it will move backwards for just that moment of quick throttle. Repeated this about 6-8 times then decided to quit. I already pulled the transfer case and disassembled it. No obvious issues. The fluid was probably original (220,000 miles). Going to put new clucth kit in since it's already torn down. Since I have the transfer case out, I'm going with your information and pull the tranny and check the clutch/sprag assembly. I was debating on this anyway. Thanks for the info. Will update as soon as I get that far.

No issues in the transfer case. Here are some pics of what you identified as the "input clutch/sprag assembly". The manual I'm using identifies this as the overdrive center shaft "sprag assembly". They appear to be the same component per the pics. Mine does seem to have flipped as the picture I saw in the link from your reply. Checking on replacement parts. Thank you for your input on this. I never would have identified this.

 

[Bekoatvb]

No issues in the transfer case. Here are some pics of what you identified as the "input clutch/sprag assembly". The manual I'm using identifies this as the overdrive center shaft "sprag assembly". They appear to be the same component per the pics. Mine does seem to have flipped as the picture I saw in the link from your reply. Checking on replacement parts. Thank you for your input on this. I never would have identified this.

Here's the pic from my transmission. Forgot to attach them last time I posted. When I removed this from the race it basically fell apart. The plastic retainer was broke in a few places.

 

[JK080]

Yep, it looks like you found it, check the race on the overdrive planet that rides in the sprag for damage, it has to be smooth. Same for the outer sprag race in the center shaft.

The best way to remove the sprag element from the center shaft is to use the three holes on the shaft side and a punch.

 

[Bekoatvb]

Yep, it looks like you found it, check the race on the overdrive planet that rides in the sprag for damage, it has to be smooth. Same for the outer sprag race in the center shaft.

The best way to remove the sprag element from the center shaft is to use the three holes on the shaft side and a punch.

Thank you. I wouldn't have noticed that issue no matter how close I looked. No damage to the races at all. I am now in hyper inspection mode before I assemble the tranny. Want to resolve all possible issues before putting it back in the vehicle. That being said, I've disassembled it 2 times. Each time the turbine / input shaft stayed in the overdrive planet It should remove easily but wouldn't. I decided to "punch" it out. The splines in the sprag were damaged, either from previous work or over torque from the tranny at some point? The shaft splines look ok. Gathering the parts to replace the planet carrier (and shaft if I can find one, local dealer says it's discontinued) Any idea on finding a new shaft? Part # XW4Z7017AA
I have a overdrive planet carrier in my Ebay cart waiting to buy. Any advice on parts availability for the shaft? I have two vendors online saying they have new ones? Little suspicious of them at this point. Again, thanks for the help.

 

[Bekoatvb]

Thank you. I wouldn't have noticed that issue no matter how close I looked. No damage to the races at all. I am now in hyper inspection mode before I assemble the tranny. Want to resolve all possible issues before putting it back in the vehicle. That being said, I've disassembled it 2 times. Each time the turbine / input shaft stayed in the overdrive planet It should remove easily but wouldn't. I decided to "punch" it out. The splines in the sprag were damaged, either from previous work or over torque from the tranny at some point? The shaft splines look ok. Gathering the parts to replace the planet carrier (and shaft if I can find one, local dealer says it's discontinued) Any idea on finding a new shaft? Part # XW4Z7017AA
I have a overdrive planet carrier in my Ebay cart waiting to buy. Any advice on parts availability for the shaft? I have two vendors online saying they have new ones? Little suspicious of them at this point. Again, thanks for the help.

Found input shafts on Ebay. Getting ready to order.

 

[JK080]

Make sure the overdrive planet turns in the proper direction, the sprag can be installed upside down.

 

[Bekoatvb]

Make sure the overdrive planet turns in the proper direction, the sprag can be installed upside down.

View attachment 446163

Got it. Clarification question, should replacing these parts (if I do it right) give the tranny reverse?
If you don't mind I would like you to look at a pic of the reverse sprag. I'll try and get it on here today or tomorrow.

 

[Bekoatvb]

A picture of the reverse sprag, it looks ok to my newly trained eye. Bought it used advertised as "A 1" shape. What is your opinion? Hope I'm not being a bother.

 

[JK080]

From what I can see it looks like it should, when it's installed into the case the drum should turn clockwise and lock counterclockwise.

 

[Bekoatvb]

Finished installing the re-rebuilt tranny late last night. What a relief, backed right out of the garage!!. Only drove it a mile then back. Shifting good, multiple reverse tries in the driveway. Working good so far. First time in over a year. No more strategic parking for awhile. Thank you JK080. Your advice on the input sprag was the key to this success. Another subject; I was having trouble getting the tranny lined up to the motor this time. Working alone, so I got some matching bolts cut the head off and made some line up dowels. Also cut the ends to replicate a screw in case they were snug after. They came right out with fingers. Attached some pics in case anyone is interested in the idea. Don't know if this is already out there, just wanted to share in case it may help someone else. I was struggling and this worked first time. Easily removed afterwards. Thanks again forum and JK080.
EDIT; Forgot to mention, only used 4 dowel pins, 1 in bottom, 2 on passenger side (pictured), one on driver side. The locations easy to access for removal.

 

[Bekoatvb]

Just an update, tranny rebuild has 2500 miles. One 5hr trip and back, one 3hr trip and back included on this milage. Doing fine. Thanks to all.