Rebuilt trans now no 3rd or 4th...

I just rebuilt my trans because it was slipping in drive and reverse. I found the brake band, reverse clutch and high clutch burnt up. I installed all new clutches, seals, and the updated oil pump gasket, and cleaned out the valve body. I put it back in the car yesterday flushed out the cooler and lines. I drove about two hundred feet in drive and then nothing. Now reverse works normal and I have forward motion if I manually shift into first or second but nothing in drive or third. I haven't had a chance to check for codes or do pressure tests. Any thoughts would be appreciated?

[Mr. Pockets]

Man, it sounds to me like you're more familiar with the tranny's internals than the vast majority of us. I hope we can help, but it sounds to me like we're more likely to ask you the questions in the future.

Does the tranny just not even try to shift to 3rd at all, or is it trying to and just slipping?

I guess you haven't driven it far enough to get a code from the TCU at all, if it was an electrical problem...

When I put the car in drive the engine rpms increase so the computer must know that I selected drive. But the engine just revs like it's in neutral. It does the same when I manually shift to third. I'm thinking maybe a piece of debri blocked a passage or a valve is sticking because I drove the car a couple hundred feet before it quit. I'll mess with it again tomorrow. Thanks for the reply.

[oab_au]

Originally posted by dekidd7457
I just rebuilt my trans because it was slipping in drive and reverse. I found the brake band, reverse clutch and high clutch burnt up. I installed all new clutches, seals, and the updated oil pump gasket, and cleaned out the valve body. I put it back in the car yesterday flushed out the cooler and lines. I drove about two hundred feet in drive and then nothing. Now reverse works normal and I have forward motion if I manually shift into first or second but nothing in drive or third. I haven't had a chance to check for codes or do pressure tests. Any thoughts would be appreciated?

I don't know how much tech background you have, but you are certainly game

The main objective in rectifying a fault is to ascertain the cause of the failure. In this case you say the high clutch was burnt up, you don't say what the high gear set was like. Did the gears or shafts show signs of excess heat?.

There could be two causes for this that I can think of (may be many others). If the cause is just a line pressure failure, caused by the pump gasket, then the facings would just be burnt.

If it was caused by the Torque converter lock up clutch facings blocking the cooler and pieces lodging the lubrication passages. Then the epicyclic gear set and shafts would be heat affected. in this case there are also other items that would be affected like the main input shaft internal seal. This separates the converter oil flow from the lube oil.

When you flushed out the cooler, was there much crap in there?

More questions, you say it goes in 1st, 2nd but not in D or 3rd. Does it not move in the D and 3rd position at all?
Does it only move when the lever is in the 1st, 2nd position only?.

If it will move in 1st and 2nd but not in 3rd and 4th, then the high clutch is not working.
If it won't drive in the D position at all then it could be the Over-run clutch, not operating.

Very hard to say as there are now too many variables, after the work you have done.

Harvey.

[gl1674]

1. Check TCU codes to make sure it is not electrical and shifts solenoids do engage. From control point of view all forward gears are controlled only by two shift solenoids - the big manual valve only switches rear/neutral/forward.

2. Check high clutch line pressure (if there is a port for it) - it will tell you whether you have oil supply problem or clutches don't work. A forgotten/misplaced check valve (steel ball) in the valve body would do it.

3. Start disassemblying it again - don't worry, after a couple more tries you'll figure it out.

If you need diagrams from the FSM - yell.

I did not see any wear on the gears or shafts. The brake band was burnt along with the reverse drum so I replaced both. The reverse clutches clutches were seized together. The facings on the high clutch were burnt so I replaced them too. All the other clutches looked ok but I got a kit that came with them all so I replaced all fiber and steel plates.

The trans was full of dark brown and black fluid but no filings or big pieces of material.

The car does not move at all in Drive. The engine revs just like its in neutral. When I manually shift the lever to first or second the car moves fine.

Thanks

[oab_au]

Originally posted by dekidd7457
I did not see any wear on the gears or shafts. The brake band was burnt along with the reverse drum so I replaced both. The reverse clutches clutches were seized together. The facings on the high clutch were burnt so I replaced them too. All the other clutches looked ok but I got a kit that came with them all so I replaced all fiber and steel plates.

The trans was full of dark brown and black fluid but no filings or big pieces of material.

The car does not move at all in Drive. The engine revs just like its in neutral. When I manually shift the lever to first or second the car moves fine.

Thanks

If it won't take off in 1st when the lever is D position, but will when the lever is in 1st position, it is most likely the 1-2 one way clutch is not operating.

Were you driving the car when the box failed?, or did you get it in that condition? If so what was the procession of failure, what went first ?

Harvey.

There is no TCM codes.
The Line pressure test is OK. 85 psi in reverse and 70 psi in all other positions at idle. 170 psi in 1st and 2nd at wide open throttle.

So I took the valve body out to inspect. I found the accumulator control valve cap had popped out. Somehow when I put the valve body halves back together the pin slid out that holds the cap in place. Must be when I put the pin back in it wasn't in the slot on the cap. So the valve was able to move were ever it wanted.

I'm hoping this is the problem. The valve does have line pressure to it.

It makes sense because the car worked in Drive for a few hundred feet and then stopped. The cap probably held until the pressure increased.

I'll keep you updated. Thanks for the help so far.

[gl1674]

If it won't take off in 1st when the lever is D position, but will when the lever is in 1st position, it is most likely the 1-2 one way clutch is not operating.

Judging by the diagrams in the service manual the 1-2 one way clutch is operated only in 1st gear only when selector is in D. Even if the clutch is out, the car still should have 2nd, 3rd and 4th gears...

Let's hope it is the accumulator valve.

I took the valve body out and reinstalled the accumulator valve properly. I still have the same problem. I am pulling my hair out at this point. I will probably remove trans again to inspect seal rings, clutch clearance specs, etc. Why did it work in Drive for a while and then quit?

[gl1674]

If it moves in 2, but does not move in 3 or D, then it is really strange - there isn't a whole lot of difference, between the two modes.
To correct my own earlier posting, the manual valve does change the fluid passages between the 3, 2, 1 and D modes. The difference between 3 and 2 is that oil pressure is applied to shuttle shift valve and overrunning clutch reducing valve.
The point here is that all the difference should end inside the valve body - clutch pressure on all clutches should be identical.

Are absolutely positively sure this is not something trivial like the manual valve linkage adjustment?

Page 97 of section 3-2 of the FSM shows more testing ports on the outside of the housing. It does show forward clutch test port - you may want to see if you have pressure in 2. It should have pressure in all forward gears in all ranges.
Unfortunately it does not show a port for high clutch (might be one of the unmarked ports next to line pressure).

If you have compressed air you might want to take the valve body out and apply pressure to the ports that control the clutches. They are marked on the same page 97. This can tell you if you have a blown seal...

My somewhat educated but unexperienced guess this is a valve body problem...

I took apart the trans again and found a seal ring that got crunched when I installed the forward drum. The seal was in three pieces so I don't think it was sealing too well. Hopefully this will be the final fix. Thanks

I fixed the seal ring and now the trans works better than ever. Now just have to fix the exhaust leak. Thanks everyone for the help.

[gl1674]

Great job!

Can you list the parts you ended up replacing, more specifically:
Did you buy the big seal kit? Did you replace clutches as assemblies or just friction plates?
What was your total part cost?

I ordered a Master kit through www.bulkpart.com
It came with all of the fiber clutch plates and the steel plates. Yes every clutch plate in the transmission. It also came with every seal, gasket, seal ring, and o-ring that I needed. It had new valve body gaskets and check balls. It even came with a lot of seals that I didn't even use. The kit was only $225.00
I ordered the oil pump gasket through Subaru because it is a better design. The one in the kit was the fiber one. I had to order a few selective sized retaining plates to adjust the clearances on the plates. The brake band and reverse drum were burnt so I replaced them along with the filter screen, about another $250. All together I figure about $700 including the 12 quarts of Mobil One synthetic ATF. It was a lot cheaper than the $2500 remanufactured trans from Subaru. I've put about 500 miles on her so far without a problem. The shifting actually gets smoother the more I drive it. I highly recommend this kit.