I need a replacement transmission for my 1980 300SD W116. I have a shot at what looks to be a rebuilt 4-bolt 722.112 transmission in a 77 280SE.

Will this gasser transmission be an OK replacement for the 722.120 transmission my car should have? Are they radically different such that it will not work at all or perform so badly that I'll need another one?

Its only $75 and I figure worst case I can probably use the front pump or something to fix the one I have.

Stop me before I buy junk again.

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80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)