saad Aqel

i just bought a E240 2001 w210 car
the past owner swaped the engine to 320 engine
so when i drive on 100km/h the RPM is going on 2600 while it should be on 2000 because of the engie replacment
can i swap the diff to a 3.07 diff and solve the problem? (the current diff is 3.67)
note: that my diff hasnt any sensor in it and this its OEM number 124 351 37 08

E55Greasemonkey

You'll need the corresponding transmission control unit to match whatever ratio the rear axle has.

saad Aqel

seriosly i have swaped the diff yestrday at the same time i have changed the gearbox fluid filter and add a 1 liter of AT fliud (notice that i had never changed it before and i dont know if the past owner had changed it or not) then the car started in a limp mode on the fourth gear i should put it on N then return it to D while driving to reach the fifth gear i have tried over 3 TCU with diffrent numbers some of them stucks on the first gear and just one has the same issue with the current TCU i also had reset the tcu by a software called xentry i think nothing happend.
do think the problem is from my gearbox ?
or its programming issue ?

E55Greasemonkey

If the TCU does not match the rear end ratio it will be in limp mode forever.

saad Aqel

do you mean there is no difference between the 240 and 320 gearbox? the only difference is the TCU ??

E55Greasemonkey

That I can't tell you, we don't have a 240 or 320 diesel here in the U.S. You would have to compare part numbers using the VIN of each vehicle for the transmission, TCU and rear axle. I do know there are different internal gear ratios for various 722.6 transmissions. The rear axle ratio is stored in the TCU. It has to match whatever is installed in the car.

saad Aqel

i have tried all the TCU's that is compatible with the 320 engine and diff still same problem.
do you think the gearbox is dying?

Plutoe

you have the gaza syndrome-----simply look in MB EPC where you will find all the applicable ECU and TCU and differentials that will or will not work for mod and or engine

saad Aqel

Update:
i have returend my old diff and every thing just get back to normal