I have a 1984 300SD with a 1983 300TD engine. I got a PnP tranny from a 1985 300SD.

The transmission failed and the quote to rebuild was $2500 to $3000.

My indy and I went to the local pick-n-pull and got the trans out of a 1985 300SD. That one is a 123 271 1901

The one we took out of my car is a 126 271 1501.

My mechanic is finding some difference that may cause trouble. The shaft for the shifter linkage is a different size. The kickdown cable is also different.

The electrics are different for the safety switch. They fit over the shift linkage shaft.

The modulator valve is green from the one in my car, and its black from the 85 donor car.


Is that enough info for one of the experts here to help me figure out what to do? Thanks in advance.

__________________
.
1st MBz: 1982 300SD
2nd MBz: 1987 300SDL
3rd MBz: 1995 S420
4th MBz: 1987 190DT
5th MBz: 1984 300SD w/1983 300DT engine
6th MBz: 1999 C230k I'm 3rd owner, got it w/57,235 miles.
and manages Mom's 2007 R320 CDI

I am not an expert. I do know, however, that the 1985 model year vehicles have a few differences from the factory from the previous years. Also, in 1985 there are California market cars (will have a 722.4) and federal market cars (will have a 722.3 (SD would be 722.303)). See the chart below, and also this thread: 1985 diesel Mercedes upgrades - Mercedes-Benz Forum


1985 FEDERAL W/S/C123 (300D/TD/CD) = 722.315 transmission
1985 FEDERAL W126 (300SD) = 722.303 transmission
1985 CALIFORNIA W/S/C123 (300D/TD/CD) & W126 (300SD) = 722.416 transmission (300SD had a different tailcone for electronic speedometer - 100% interchangable with mechanical version)

I hope this is at least somewhat helpful, and that someone with more (and better!) information will chime in.

-Chris

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Christopher
'06 Mercedes E350 station wagon (silver/black)
'85 Mercedes 300D (black pearl/palomino)
'85 Mercedes 300SD (smoke silver/burgundy)
'79 Cadillac Sedan DeVille

'05 Toyota Camry (because always running is nice)

'85 Mercedes 300D sold back to orig. owner 8-1-06
'84 Volvo 264GL Diesel, owned 2000-2013

I found this cross reference for transmissions.

Mercedes Benz 722.6 transmission application guide

This info should be made easy to find, its really a good resource for swapping transmissions.

__________________
.
1st MBz: 1982 300SD
2nd MBz: 1987 300SDL
3rd MBz: 1995 S420
4th MBz: 1987 190DT
5th MBz: 1984 300SD w/1983 300DT engine
6th MBz: 1999 C230k I'm 3rd owner, got it w/57,235 miles.
and manages Mom's 2007 R320 CDI