Hard 2-3 shift then at med throttle

[Silver X]

Title should be "Hard 2-3 shift at med throttle".

My 5R55E has been acting strange sometimes since I did some trans work earlier this year. I added a Superior VB kit, replaced all the solenoids, torque convertor, pump, input shaft, seals, bearings, and adjusted the bands. The rest of the internals looked fine, so I didn't replace anything else. It was great for a couple of weeks, but started acting funny once in awhile. Eventually the hard 2-3 shifts were happening all the time.

Now....
At light throttle, everything works normally. All shifts are smooth and quick.

At half throttle and up, 1st to 2nd gear shifts are great. 2nd to 3rd shifts nice and firm, but then immediately seems to engage a brake for a half second, then releases and continues to accellerate. Sometimes it'll lock up hard enough to drop a couple thousand rpm and get belt squeal on the engine. 3rd to 4th is nice and firm without anything unusual. 4th to 5th is fine too.

I have the trans apart right now....had the engine out and figured I should open the trans while its out. I found that the friction plates in the Coast Clutch are destroyed. All the teeth on all the plates are almost completely chewed off. The intermediate band looks a little worn now too. The Direct Clutch friction plates look fine. All the gears have some visible wear, but not too bad. Trans fluid looked and smelled normal. And it should, since it is only a few months old. All the internals except the input shell (old has windows for ISS, new one doesn't) are going to be replaced with parts from my other trans (11k miles). Those parts look like new. The trans is about halfway back together now, but I ran out of time and motivation tonight. Its really freakin cold out there and I only have a little electric heater. Can't even feel it 3ft away.

I don't know what would cause the shifting problem. Only thing I can think of is the intermediate band was adjusted too tightly. Not sure what else would cause the lock-up after shifting. Need to figure it out before everything goes back in the truck later this week.

 

[Silver X]

The trans shop I talked to had no idea what it would be. Just said they hate working on these transmissions, because of all the strange problems....then said good luck finding a place to fix it. And that was before I told them I had it apart. Then the guy just laughed. I wasn't going to give them work anyway.

Here are the clutches:

Intermediate band:

 

[BrooklynBay]

You could get a new boost valve with O rings, end plugs with O rings, and a manual shift index sleeve such as this one: http://www.transmissionpartsusa.com/A4LD_Manual_valve_index_sleeve_p/400-005694701.htm

 

[Silver X]

I don't know much about how auto transmissions work. All I know about the 5R55E is from reading the ATSG manual and reading some threads here. Then physically taking one apart and reassembling it. What each circuit in the VB does is still kind of confusing to me. Some of them seem to control several different things and overlap with other stuff.

Are you thinking too much pressure is bleeding off during the 2-3 shifts?


If I have time after work tonight, I'm going to put the rest of the trans back together except for the VB. I'll try to get those parts for the VB if they can ship before the weekend. The truck has to be completely finished by Saturday...engine is back together, but still needs to be installed too. Sucks right now, I'm working long hours and have very limited internet usage. Can't do much searching to try to learn about this stuff.

 

[Silver X]

Well, still haven't had a chance to work on anything yet. Planned on working on it today, but got called into work instead. I'll gladly take the 10 hrs of overtime, and the truck can wait. Gotta work 10 hrs tomorrow too.

Would be nice to get the truck back together before I forget where everything goes.