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300SDL transmission question

I recently had a rembuilt transmission installed in my 86 300SDL. The mechanic said to bring it back after about 1000 miles to ahve the fluid and filter changed. The day after i had that done, it began to act strangely. It seems to have no power near the higher end of the gears. If i keep my foot in it, it would normally shift about

4000-4500rpm. Now it just doesn't have any more pull to it after 3000. It will still rev passed 3000, just no more pulling power. Once in 4th gear it is very hard to get it passed 3000rpms. To getr it to shift, in the lower gears, when the power level is reached, i have to let off the accelorator. When i do this from 1st gear, it will shift into second for just long enough to feel it then it shifts into 3rd before you can even put ther pedal down again. When in 4th, nothing over 1/2 pedal seems to make any difference. It does not rev and not pull, like it did with the last transmission. It just seems to have no power. If i move the gear selector from 4th to 3rd the engine will rev higher but the transmission does not pull harder. I can't get passed 80-82 mph now. The menchanic is on vacation and will not be back til Monday. Will it hurt to be driving it til then? What can i look for and where? Thanks for any help, Shannon 86 300SDL 289,000miles 80 450SL 218,000 miles
Reply to
Shannon Pelley
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  1. Just drive it, no harm will be done so long as the fluid level is between the dip stick's H and L marks when checked hot and with engine at idle.

  1. Suspect the cable from the throttle linkage to the transmission is disconnected or broken. Its function is to "tell" the transmission the throttle position so the box will downshift when the driver steps on the accelerator. You can take a look at the upper end of this cable - it probably connects to the throttle linkage at the top rear of the engine and goes down to the right side of the transmission.

Reply to
T.G. Lambach

Could that cause it to lose top end speed? Putting the cruise control on at 75-80mph, the pedal stays almost all the way on the floor, while only at 3k RPM's. Mileage doesn'rt seem to be affected, but it just seems to be killing itself to run at speed.

Reply to
sdp1

Suggest you check the throttle linkage and the motor mounts, the latter come to mind since the transmission was removed. A broken mount will allow the engine and transmission to sag out of position for the throttle to work correctly, among other things.

Reply to
T.G. Lambach

Mechanic checked it over and found a faulty "transmission module"? What is this module and could its failure be related to the transmission being replaced, or to the fluid and filter having been changed the day before it went out? The car has 289,000 miles. Is the timing of the failure just a coinsidence? thank you

Reply to
sdp1

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