Rebuilt 5r55e reverse not working

[Glacier991]

Did you replace the EPC? The Transfer case COULD contribute as well, but I always worry about low line pressure rise with an aging 5R55E EPC solenoid. The good news is that there are serveral pressure taps on this transmission where you can test pressures.

 

[edseven]

I'll pick up a pressure tester and take some readings.

If the pressure is normal in all gears re:thread on how to use the pressure tester, then should I start looking at the xfer case?

IF pressure is low in reverse (my problem area) would that more likely be the modulator valve malfunctioning rather than the EPC? If the EPC was bad wouldn't I have low pressure in all gears? Should the EPC and boost valve be changed in tandem?

How should the vb pcs feel? SHould they slide in an out of the bores by gravity alone or should they need a little tug? If I find one that is sticking can I polish it up with some 400 or 600 grit sandpaper or do I need to get a kit to ream and sleeve the bore?

When I put in the FORD TSB thats all I did. I pushed on the other valves but did not remove them. I tested the solenoids and they all fell in spec for what its worth.

I'll report back this weekend after the pressure test. This vb thing really is doable. I hope I just need to do a more complete cleaning and add the EPC boost valve to fix this thing.

Whats the deal with the reverse servo? The ones I see on line all look like rubber plungers. Mine is a metal disk. The original one fell out when I was changing the seals. After changing the seals the servo stays in the. It moves up and down with light pressure from my palm but it doesnt fall out of the bore. Also, the cover has no gasket. The servo looks ****ed now but still get engine braking and manual first. Should I try the tip extension for this?

 

[BrooklynBay]

The reverse servo isn't like the other 2 servos. This one has 2 grooves for seals. I would recommend the viton "D" ring kit. There are 3 sizes. Just get the correct size, and don't waste time with one of those grindable extension tips. Measure the depth first with a depth gauge before buying the part. The servo cover has a gasket.

 

[BrooklynBay]

Here's a picture of the low/reverse servo from Glacier991's photo gallery:

Your 5R55E doesn't have this big spring. This picture is for the A4LD.

 

[trlemarr]

I took the valve body apart.I did not now what bore was what so i checked all of them what i did find is (part number 31 thermistat by pass valve in the valve body blow up) was in backwards Do you know if this was a direct cause of it not going into reverse.

thaniks

 

[BrooklynBay]

It worked up until now with it installed backwards. The bypass is for the cooler.

 

[Glacier991]

It could be... reverse is a boosted pressure that might have overcome the cooler bypass.

 

[trlemarr]

no it did not go in to reverse before now i have put it in the right way i was just wondering if that could have been the problem since you say it could have been i guess i will have to reinstall it and see if it works.

thanks

 

[trlemarr]

ok put rebuilt valve body in seemed to work. Drove to work next day 15+ miles 4 to 5 stop sighns got to work parked truck. After work went to leave backed out of parking space put in drive will not engage. Put in first tries to go back wards just barely. So no forward in drive and 2nd they seem to be in neutral 1st tries to pull backwards. reverse works fine as well as neutral and park. swap back to the donor valve body same exact thing.

any ideas if not anybody in southwest washington interested in a 97 xlt and a 98 4 door with thee crap trans

thanks

 

[CurtisL]

ever figure out the problem? i have the exact same problem and i dont know what to do?

 

[CutterJon]

Intermittent no Reverse in 5r55e

This is an old thread, but has some similar problems to mine.

I lost reverse a few months back, then went through all the steps mentioned here-I installed a rebuilt valve body (with new EPC, other solenoids tested), and then replaced the reverse servo piston. I can see that there is a mark on the band itself when I look into the bore-it looks exactly like the tip of the piston-kind of cratered. Installed new D rings.
Also, changed the filter and added a remote filter and flushed the fluid a few times.

This all only mostly fixed it.

My problem now is rough shifting between first and second, and occasionally-rarely, but always at a bad time-no reverse. Just revs. When R is out, manual 1st will work, but it clunks into gear. (the band is not broken, the piston usually works)

I sometimes can get into R by shifting down to 1, then back to P then into R, but not always. No particular combination seems to do the trick. I usually need to drive a short distance in D, then R works fine. Sometimes just waiting 10 minutes will work. Today, I was stuck at the top of a parking garage ramp with no R after lots of back and forth shifting, then rolled to the bottom and got R on the first try (with a clunk).

The only "easy" things I haven't done is the DTR and the wiring harness.
It seems like it would still shift between 1 and 2 smoothly with a bad DTR, though (?)

I pressure tested it and was getting strange dips in the pressure, pressure was generally low, but nothing that was obviously a problem.

Does any of this sound familiar to anyone? I can't find many threads for an "intermittent" no R problem.
Could it be a clutch? The pump? A bad VB rebuild? A warped Servo piston bore?

Thanks!

 

[AROC]

Man I just got back from a camping trip in the woods, we were in a tight spot and I was reversing and then suddenly this big bang sounded under my truck, I thought I hit a Rock or something. put in drive to check it out and when I wanted to back up guess what NO REVERSE at 1 am in a pitch dark forest haha we were able to push enough just to U turn back to the trail. I think it is blessing in disguise and wanted to see what you think. It is a 99 sport 4x2 and cuurently very interested in turning into 4x4 and puting in a SAS in the front (OFFRAOD RIG). Should I try and Fix the reverse? or should I just go and put in 4x4 transmision with a transfer case and start my swap? Depending in how much the shop will charge me to fix the transmission or if I can figure out how to to make it work will help me decide. Maybe its just the kick off i needed to start my project haha

AROC