Newbie Merc owner with a 1988 W124 260E Automatic Transmission issue
 

I'm a newbie here and recently acquired my first old-school Benz. It's a 1988 W124 260E and i very happy i got it. As with many pre-owned vehicles, there are usually some things that need to be fixed.

For my 260E i believe the issue is the 4-speed Automatic Transmission (model 772.409). Here are some of my concerns. Perhaps experienced owners can give me good advice on what to do:

1. 1. I noticed a sudden jolt every time i shift from P to R.
2. 2. When driving on D, car sometimes also jolts from 1st to 2nd gear. This happens especially when i slightly release the gas pedal before it shifts. However, if accelerating, it shifts smoothly.
3. 3. Once on 2nd gear, it shifts to 3rd gear right away, only after a few seconds, without going through the usual power band for 3rd gear.
4. 4. It doesnt seem to shift automatically to 4th gear. However, if i accelerate and manually move the shifter from 2-3-D, it goes into 4th.

The transmission shifter bushings needed replacement and so i had my mechanic do this. At this time i also had my mechanic check the vacuum to the modulator and the modulator itself. They had this special tool to check pressure. It was the first thing they checked and according to them, pressure was okay. Pressure is 3.0 for my 722.409, and up to specs. So the mechanic said it could be blockages in the valve body and/or issues with the lining.

The rubber disk coupling had also been replaced recently.

With these symptoms, what could the problem be? I'd hate to think that i need to overhaul my tranny. Hopefully i can still fix it without taking the transmission down.

Could it be the downshift switch under the gas pedal? I've also heard that the use of the additive "TRANS-X AUTOMATIC TRANSMISSION SLIP-STOP & LEAK FIX" really works and can free up a blocked valve body and prolong the life of a tranny.

I live in Manila, Philippines and the cost of a surplus tranny will is sky high, the same goes with the cost of overhauling my existing tranny.

Hoping for your expert advise!

Cheers!

The first thing to check is vacuum. There is a vacuum modulator on the side of the tranny. You can quick check if it is working by disconnecting the vacuum hose and seeing if your shifting gets rougher. Or, use a Mity-Vac and see if it holds vacuum. Also check the hose and other connections for vacuum leaks.

Couple Questions
 

You didn't state the mileage, whether the tranny was original, or the last service date of tranny fluid & filter. More info would be helpful. And do not put any additives in such as you mentioned. You're not buying time, you're buying trouble. I have an '89 260e.