Auto Tranny not catching first gear?!? HELP
 

Did a search, nothing like what I am going through I could find.

This has really been a confusing process. At 120k, It was at the dealer, and they did the Auto Trans Cooler Lines because they were leaking. At that time, they diagnosed the Flex Disc as being worn and need replacing. At about 122k, the car started slipping/not catching first gear, and slipping if floored. However once in second or up, totally fine. The car can cruise at 100, a full pedal to the medal at 40 drops into second all the way to 60, and no slippage.

So when I went to the dealer to get the flex disc replaced. It didn't solve the problem though. At further inspection, dealer said ATF fluid was 5 quarts low. They said they only needed to add 2 quarts when lines were replaced cause a little might have leaked, and then a quart for taking the lines off and loosing ATF fluid there. However, they had no explanation for 5 quarts low. No leaks from the lines they said, and no leaks are apparent. My father believes they probably forgot to add the fluid in, and probably loss more then that when changing the lines, or that when changign the filter, didn't add any either. They blame me though for driving 2k miles and not checking my fluids, when I've never had to cause the cars is especially clean, engine, everything. Car came right from the dealer, so I didn't expect anything.

However, the dealer left the diagnosis ass the transmission, and they don't service MB trans, only replacing with new ones, which is $4500 brand new installed. I quickly took the car, and got a second opinion. This was at AAMCO, and they said its probably a torque converter. The third was an independent MB mechanic, and they said its probably the Friction Plate inside the tranny, so a new trans is in order.

Took it to another MB Mechanic, and they said they would believe its the torque converter also, because stand-stills are when the torque converter really works. When moving, its perfectly fine, and you wouldn't think the car has a problem.

So that said, what could it be. I really don't want to buy a used trans, and it not be the problem, am not spending $4500, and if it is a torque converter, does that sound right.

The car reverses fine, and once out of first, no slippage ever. Goes through all gears, could cruise at 120 all day, be floored from 60 to 100. I know I have done it. The only thing is if it were a bad tranny, wouldn't the other gears not work. Or wouldn't first be messed up, cause once caught, its pretty much fine unless floored?

I really gave the best diagnoss I could, any help is great, and would even pay someone at this point that saves me mega $$$$$

Thanks.

First gear uses the largest band in the transmission as you need a lot of torque to get going. Sounds as if the piston that applies this band isn't working properly.
The piston has a "teflon" seal & there are various size adjustment pins to change the band clearance. FIND a local shop that will try to replace this seal & adjust the band(in car).
Should be able to do this in 2.5hrs & $25 or less in parts.