car won't reverse!!!!!!!!!! HELP!!!!!!!!!

[kirk240]

I have an auto '83 240D that for a while has occasionaly locked up in reverse but just running the shifter through the Gate a few times fixed it. then yesterday at lunch break I had a really hard time getting it to reverse but finaly got it going (my muffler hangers vanished on the way down the mountian but that is a diffrent story). sence then it has just gotten worse and finaly today gave out completly. the car goes foward in reverse... some times. no one else seems to have this problem I am takeing it to a shop on monday that replaced my moms traney a while back. any advice would be apperceated.

thanks

BTW... about how much extra would it be to have a stick put in the car? now seems like a good time.

[mechmagcn]

I'm also interested in hearing responses for this one. My 81 300 SD sometimes will try to reverse and then stop like it is trying to go forward also(like it is in two gears at once). Other times it works just fine.

[kirk240]

it took mine about a year from when I noticed it for this to happen
exact same thing and also exactly what I thought

[TonyFromWestOz]

How long since the tranny has been serviced?
Is the fluid level correct?
Does the fluid smell burnt?
What have you done since first noticing the fault, to remedy the situation?

[leathermang]

Look up ' trans-x' and follow the procedure first... to include changing all your fluid ( TC also )... this is the cheapest best chance for either fixing or pointing out what is not wrong....

[kirk240]

Originally Posted by TonyFromWestOz

How long since the tranny has been serviced?
Is the fluid level correct??

I dont know it seems to full but I have never gotten the same reading twice it was flushed and filled nov. '03 doesn't smell burnt still looks new I dont drive enough to need it changed yet

Originally Posted by TonyFromWestOz

What have you done since first noticing the fault, to remedy the situation?

the lock up didn't seem to bad this happened really fast and I havent had time to crawl under the car to have a look.

Have you looked at the shift linkage from shifter to tranny?

[Glinko]

Off topic but mildy related; my mother owned an early 60's chevy impala (during the 70's) that did not have reverse.

She used to have to be strategic when she parked it. Like one time someone parked in front of her and she had to wait until they came back to their car before she could leave.

[kirk240]

Originally Posted by BusyBenz

Have you looked at the shift linkage from shifter to tranny?

what should I look for?

[davidhoward]

My experience/knowlege is limited to the 722.1xx/722.2xx automatic transmission. It may apply to newer transmissions, but I do not have the manual or experience with them, so don't treat the following as gospel .

If the linkage checks out O.K., and it is an automatic, it sounds to me like the B3 brake band is not engaging. This could be because it is too loose (it is adjustable from outside of transmission), or the B3 servo might have a major internal leak (possibly repairable in-vehicle), or the band is completely worn out (need to remove transmission to replace).

If you remove the tranny oil pan, and valve body, you can use compressed air to verify correct operation of B3 servo/band. The B3 servo/band is used only for reverse.

You may find the piston/cylinder is damaged, however, beyond in vehicle repair . The fact that it would get stuck in reverse doesn't sound like a simple leaky piston or wear to me . See my experience with B2 cylinder wall wear in link:

722.118 transmission B2 servo/piston

Also has nice pictures of tranny with valve body removed...

There is a rod fitted/connected that extends from the gear shifter to the transmission gear lever. The rod has clips that hold it connected and fail with age.

Drive the car up on some ramps, and with the emergency brake on, tires chalked, (safety) crawl under and and look (drivers side) up between the transmission and transmission floor hump and you should see this rod, about 12 or 15 inches long, 3/8" diameter. have someone move the shifter back and forth. At this point, it should become clear if the shifter rod is moving the transmission lever located on the drivers side of the transmission. You should be able to tell right away if something is amiss! Hopefully it is just this simple and all you need to do is reconnect the rod and clip that holds it in place. If not, it could be something wrong internally with the tranny........good luck...BB

[leathermang]

"If the linkage checks out O.K., and it is an automatic, it sounds to me like the B3 brake band is not engaging. This could be because it is too loose (it is adjustable from outside of transmission), or the B3 servo might have a major internal leak (possibly repairable in-vehicle), or the band is completely worn out (need to remove transmission to replace)."


Is there anything in the transmission valve body, or anywhere else, which, if constricted by varnish build up ( potentially cured by Trans-X ) which could cause the B3 piston to not work ? IE, is the B3 piston controlled by or does it control anything else which would stop working if some little hole were blocked by varnish ?

[davidhoward]

Originally Posted by leathermang

Is there anything in the transmission valve body, or anywhere else, which, if constricted by varnish build up ( potentially cured by Trans-X ) which could cause the B3 piston to not work ? IE, is the B3 piston controlled by or does it control anything else which would stop working if some little hole were blocked by varnish ?

In My Humble Opinion, no (sorry) .

I've tried Trans-X in desperation on more than one transmission , and while it may have marginally helped for a short time (probably my imagination), the problems didn't go away completely or for long.

Here's what the Automatic Transmission Service Group (ATSG) Mercedes 722.1 722.2 TechTran service manual says:

Trouble:
No power transmission with selector lever in position "R", all forward gears in order
Cause:
1. Band brake B3 wrongly adjusted
2. Band brake B3 and/or lining badly damaged mechanically
3. Free wheel defective
4. Working pressure too low or completely absent --- lip sealing ring on band brake B3 damaged

All of these 'causes' can be tested by removing the pan and valve body. This can be done on jack stands or ramps in a garage or driveway in less than an afternoon. They could also be done by any decent transmission shop.

[leathermang]

It will only work for varnish build up .... but it is a cheap thing to try first and has helped out a bunch of cars... a couple of them mine... in dramatic fashion....
If you can suck out a couple of quarts of trans fluid from the top of the car and put this in ( less than $20 even if two cans are needed for initial application ... my 81 wagon needed that much ) it is a clean and quick attempt that does have some chance of success....

[kirk240]

took it to the shop this morning...the good news...I might put a stick in it...the bad news...I need a new transmission. he said the drive cluch was welded together. he had never heard of changing a car to a stick though so...problem solved