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blindwolf 04-16-2008 04:46 PM

Transmission a no-go
 
Several weeks ago, I backed out of a parking place and the car has not moved under its own power since. I pulled the B2 piston, it looked good, so I reinstalled it. Replaced fluid and filter at the same time. Still no go. Ran a couple of cans of sea foam trans cleaner through it. Still no go. Jacked all four wheels off the ground to check drive line, everything looks good. Started the car and put in gear, the rear wheels spun like they are supposed to except for reverse, which was still rotating in a forward direction. When I drained the fluid it was not burnt and had no solids in bigger than what would not go through a coffee filter. There are no leaks from either the front or rear seals. I have about run out of ideas,. short of overhauling the tranny.

turbobenz 04-16-2008 04:51 PM

isnt there a band or something that you can replace/adjust that is related to reverse not working?

blindwolf 04-16-2008 05:10 PM

There is a reverse band, but I still don,t know why the tranny works in the air and not on the ground. I am guessing torque convertor, but that is only a guess.

imagesinthewind 04-16-2008 05:11 PM

Reverse Band Adjustment.
Tranny must be the 722.1XX for that adjustment

lietuviai 04-16-2008 05:12 PM

I had similar symptoms except the car would go in reverse perfectly but no forward movement unless I really revved it but even then it barely budged.
When I put it on jack stands it too would run and shift normally.
My B2 piston was perfect but perhaps the piston rod had fallen out which they do if not carefully reinstalled. On another try with the rod carefully installed, I blew the B2 cover seal when I put in drive without any forward movement.
I pretty much gave up on that transmission since it blew that cover a second time even with a new seal.
I found another tranny reasonably cheap and it's been fine so far.

blindwolf 04-16-2008 05:25 PM

The tranny is a 722.315

dawsonj3 04-16-2008 06:05 PM

So, the car will not move in any direction with the wheels on the ground? Perhaps the torque convertor has failed, or perhaps the fluid pump within the tranny died. It's also possible that one of the shafts within the tranny has broken, although this is less likely.

In conclusion, you've moved beyond DIY territory. You should take it to a transmission specialist.

Have you checked the shift linkage to determine whether it is still firmly attached to the transmission?

blindwolf 04-16-2008 06:17 PM

Yes, I have checked the complete shifting system for proper engagement. The torque convertor and front pump are not out of the realm of DIY, it just takes time dropping the tranny. With the tranny down, the torque convetor just slides on or off the imput shaft and the front pump is held to the bell housing by bolts and it too slides on or off the imput shaft.

blindwolf 04-17-2008 09:15 AM

bump

kingdoc1 04-17-2008 09:45 AM

Have you checked line pressures? I bought a car with a similar problem once and it had no pump pressure. After I pulled the torque converter I found the small ears that drive the front pump sheared off. If you buy a ATSG manual for your trans it will show you test locations and procedures.

blindwolf 04-17-2008 09:57 AM

That sounds like a good next step. Thanks

rs899 04-17-2008 11:34 AM

I can't say I know what the problem is, but I am fairly sure someone will have to pull it to figure it out. A total rebuild CAN be a DIY, just an involved one.

Rick

lietuviai 04-17-2008 11:42 AM

Quote:

Originally Posted by kingdoc1 (Post 1827177)
Have you checked line pressures? I bought a car with a similar problem once and it had no pump pressure. After I pulled the torque converter I found the small ears that drive the front pump sheared off. If you buy a ATSG manual for your trans it will show you test locations and procedures.

I have the ATSG manual and it is a POS. You might be able to reference it for the test locations but other than that I would not use it to try to do anything more involved. The illustrations are crap and the step by step info leaves a lot out.

blindwolf 04-17-2008 12:02 PM

Thanks for the heads up, I was fust about to drop $25 on one.

kingdoc1 04-21-2008 09:38 AM

Sorry, I didn't mean to imply that ATSG manual will tell you everything, but it does show you the test points. I suggested that you check pump pressure first, because if there is no pressure it suggests a possible pump failure, and at that point you know you will have to pull the tranny, while correct pressure indicates a possibility that there is another problem that could be fixed more easily, possibly without pulling the tranny.


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