Update to a 7 spd

[Charity's Van]

I have a 2007 Sprinter with high miles and a bad engine. I am considering putting another engine in it and returning it to service. Is the 7 spd that is in the newer vans compatable with the OM642? I am looking for mods to increase fuel mileage and longevity. Anybody know what this may entail or who to contact that may have experience?

 

[FlyingVan]

The 7 speed is a sweet transmission. A few years ago I bought a family hauler Sprinter with the 2.1 liter 4 cylinder and the 7 speed transmission. I believe this is the best combination Mercedes put in a Sprinter. Nowadays they also put this transmission behind a 6 cylinder.

However, replacing a 5 speed with a 7 speed has about 2% success rate if possible at all. Unless you know someone that has done it and was successful, do not waste your time and money. Someone mentioned that a Sprinter is a computer on wheels and they were not far from the truth. Actually, the sprinter has about 7 or 8 computers in them, with some of them being coded with the particular vin number of the van, meaning you cannot take the same computer out of an identical van and make it work in another van.

If you want a 7 speed, retire the 2007 and buy another one with the 7 speed transmission.


Sent from my moto g(7) using Tapatalk

 

[LDB]

I'm not very mechanical/technical so this may be a crazy question. What is the final drive ratio of the 5 and 7 speeds? Since so much of expediting is long distance highway driving would changing the ratio in the 5 speed give at least some of the mpg improvement, on the highway portions at least?

 

[danthewolf00]

Might just be cheaper to change the gear ratio in the rear axle.

 

[Charity's Van]

the 07 is computor complicated enough, i am considering putting another drive line in it and was on the quest for optimum fuel economy at the same time. that is the reason for questions about the 7 spd. thanks for the replys

 

[danthewolf00]

The rear end is the easiest change to do and reprogram the computer.....if you change the transmission you need the computer for it AND drive shaft then reprogram it....you can even change tire size and get different fuel mileage.