300D with 240D Automatic tranny ?? - PeachParts Mercedes-Benz Forum

sun tortise · #1 09-26-2013, 11:42 PM

Considering buying an 81 300D nonturbo that has an automatic transmission from a 240D. Does not work correctly, won't shift into gears higher than second.

Can a 240D tranny work properly in a 300D? and if so, what would be the likely cause of it not shifting into higher gears?

How could I tell an non workable transplant from a defective transmission from a vacuum problem or something else minor and fixable?

What should it cost to pay someone to do a transmission transplant?

Thanx! This forum has been really helpful so far!

ROLLGUY · #2 09-27-2013, 12:23 AM

As far as I know, they both have the same trans (722.1XX). I have both a 240 automatic, and an '81 300D (617 Turbo installed), and the trans is the same on both. As for the shifting, I can't help you there other than check the modulator. I replaced one in my old '81 CD, and it did not shift out of first after that. I had to take it to a trans shop, and they took it apart and fixed something inside ($750 cost).

sleepstar · #3 09-27-2013, 12:25 AM

what year is the 240D trans? early ones don't use vacuum from the vcv to control the shifts. you'd need to get the control rod for one of those.

Zacharias · #4 09-27-2013, 12:45 AM

I had much the same experience as Rollguy, and ended up with a similar transmission shop bill on my '80 300td, The 300td has the trans out of a 1983 240d that I owned previously, but didn't want to shift up from second after sitting in storage for about five years.

My problem was a stuck governor. I believe other things can also cause the problem, however.

First step is to determine exactly what model of transmission you've got. It's on the passenger side of the casing, above the pan lip. You will likely need to clean off some grime to read it. It will be a 722.XXX number.