1989 420 SEL no power going up grade
 

I recently replaced the tranny in my Benz and all of a sudden I don't have a any power when the car is going up grade. Its fine on flat ground, but when I depress the accelerator, going uphill it seems to have no power at all. I've already had a tune up done to the car. Any suggestions.

Who did the work on the tranny? Was it a DIY?

Hello,
The tranny was done by an auto repair shop. It drives great on level ground but when the car starts to climb there is definitly a problem with acceleration. It loses all power. The RPM shows no movement. Appreciate all the help I can get. Thank you

loses power on highway speed
 

Hello,
the fuel pump has also been replaced as well as the gas regulator. What could be next? Car loses power at highway speeds and then picks up. The car in question is the 1989 420 SEL.
Thanks for your help.

Try adjusting the Modulator, even though it is for hard or soft shifting of Tranny but I found it to be effecting the pick up of the car. I would assume your car was running Ok before the Tranny chnage, so may be new tranny need adjustment.
Is it a new tranny or rebuild or used?
Did you trid changing the Fuel filter?

I hope it help. Keep us posted.
Thanks