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Discussion Starter · #1 ·
I have a strange automatic transmission problem I can't explain, and I'm hoping somebody here who know more about it might be able to explain it to me.

Basically, sometimes it is as if you are pulling a sled in a truck-&-tractor pull when going in reverse. You have to rev it up to start moving and rev it higher and higher to keep going in reverse. The car self-brakes to a sudden stop if you let off the gas.

I suspected the parking brake self-adjusters, but with both rear wheels off the ground they rotate easy enough either direction by hand. If I put it in a forward gear the wheels start to rotate as I release the brake as they should. But with both rear wheels off the ground, the engine idling, and the shifter in reverse, I get nothing unless I raise the revs.

In fact if I spin one rear tire by hand with the engine idling and the shifter in reverse, the other spins the opposite direction. This tells me the transmission is not trying to spin the driveshaft in reverse until I rev the engine up higher. Or if it is trying to spin it, something inside the transmission is resisting and no force is transmitted to the driveshaft.

Any thoughts on what might be going on in there?
 

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Tranny expert needed,here.

Maybe Junkie has an answer. Seem to remember how an over running clutch works-maybe the rollers fell out and it's locking up.Many systems come into play while in reverse.Sorry,see a tranny shop.:duh: Dave in Seattle.
 

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Sounds like a torque converter problem. Locking up at low speed and reverse. Try unplugging the transmission computer and see what happens.
 

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Discussion Starter · #4 ·
I drove this car to work this morning, and it is definitely worse after a spirited 20 minute drive then it was when backing out of the driveway. In fact, I found it impossible to back into a parking spot at work. Put it in reverse, give it some gas and it starts to move backward but slows so I give it more gas. I moved about 10 feet backward before it has slowed to a stop even with the rpms over 3500. I let off the gas, in reverse on level ground, and the car moves FORWARD slightly. This transmission is definitely shot, but I'm still really curious what is going on in there.
I'll try unplugging the computer and let you know if that effects it any.
 

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Nah, not computer controls-Bad L/U solenoid will actually kill engine. Dave may have hit it on the head-One way clutches(sprags) are used instead of bands to hold a clutch against a case journal/shaft inside trans. Dont have a service manual here, But I would bet that if you pulled pan off, you would see either lots of Metal, or fibre, or actual pieces of sprag..
 

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It maybe just a bad valve body gasket or your sprag gear for reverse gear has cracked and the load on it spreads it out. Just like the LSD gears that go bad and split.
 

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Discussion Starter · #7 ·
Something under the car snapped on the 1-2 or 2-3 upshift this morning. The revs went up but the car coasted down and I thought the transmission had quit entirely. I stopped and looked under it with the car idling in Park, and the driveshaft jolted several times as if getting sudden force from the transmission. Probably ingesting bits of metal from whatever just broke.

I figured it was FUBAR and I couldn't hurt it any worse and I was only a couple miles from work, so I put it in drive and brought the revs up. A bit of smoke from burning transmission fluid and the car began to move. It will gain speed slowly by reving it up a lot and get up to 55. Amazing it hasn't stranded me as this transmission is certainly self-destructing. About 350,000 miles on this transmission.

I may try and drive it the 20 miles back to my house if I don't feel there is much danger of the driveshaft coming loose, but I won't be surprised if the hills are too much for what is left of the transmission.

I appreciate all the help here, but I think I'm about to give up on daily driving 25 year old high-mileage cars. Looking for a mid 90's BMW 325 or 328...
 
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