Intresting Diesel Conversion (help)

[Diezel_guy]

Hi guys
About a year ago i did a 300sd motor swap with a 4spd 240D transmission in my 1990 YJ jeep. the rig has good TQ but the top end has yet to be desired,1st gear is really too low, but on the highway it revs too high, the 4x4 works fine, i have 4.10 axels and 33" tires. so im wondering should i look for a rare 5spd tranny that came with the 300sd motor in europe, or should i have a tranny shop take alook, or a new tranny all together. I should be able to pull a small trailer with a atv but the power is not there. I would also like to mention that the motor was rebuilt, any suggestions??

thanks

 

[Hibbo]

Are you saying that it is not powerfull enough to tow your trailer, and that it revs to high?

If that is the case then I think a new, more powerfull engine is required! No gearbox can solve those problems!

If I have got the wrong end of the stick let me know!

Is it a om617 engine (5 cylinder, as used in the w123) or om603 (6 cylinder as used in the w124)? Turbocharged or n/a?

If it is a 603, then there is a 5spd autobox that should fit, it was available on some late w124s, and is basically a normal 4spd hydraulic box with and electriconically controlled overdrive module bolted on the back.

 

[Diezel_guy]

i think its a om617 engine 5 cylinder, 1980 300sd model, im pretty sure they had 5 spd models for the 300, i remember seeing a mercedes g wagon on ebay that had the 300 motor with 5spd and 4x4, thx

 

[Hibbo]

There was no 5spd auto available on the w123/w126s that used the om617, I'm pretty sure of that.
Not sure about the G-wagen though, it was available till the late 80s still using the 617. But Merc didn't introduce 5spd autos till the early 90s as far as I know.

If the bellhousing and driveplate are the same on 617 & 603 engines, then a 5spd may well fit.
Good luck!

 

[Diezel_guy]

how easy is it to get a 5spd tranny from a 617 & 603, i can get a plate made to mate the motor and tranny, but im in toronto canada, are these avaiable in the uk???

 

[240D 3.0VNTi]

The engine and tranny are completely incompatible between the 617 and the 5-speed from a 602/603. The tranny body is an all aluminum 1-piece and the starter warts are on opposite sides of the engine.