Need info source: physical differences between rear differentials amoungst w203s
I'm ready to swap a lower ratio rear differential into my 06 c350 @ a 2.83.
3.47 and 3.67 are the lowest available as OEM pumpkins. The 3.67 is the most desireable, found in the early c240s. The 3.47 I have found in a c230k as late as 05. I believe the switch to the 2.5L m272 precipitated a lower ratio in the 06 and 07.
I need to know what differences between the pupmkins I need to phsyically be able to distinguish so that I will know if the donor pumpkin can be a direct interchange candidate... or not.
This came as a surprise from splinter, as I was under the impression all the rear diff's were physically the same minus the ring gear/pinion inside.
Not knowing any better, I would asume the 3.47 would be a better candidate as it came in a facelited 05, versus an older say 2002 3.67 from a preFL c240.
Thank you
considering i found the 3.46 out of the 05 with only 21k miles for ~$300, I may be forced to pull the trigger on that due to fears around the pumpkin out of an old c240 being the most likely to not swap in place... and the fact the c240 3.67 is going to have the most # of miles.
someday when I have a more endless supply of money I'll get the Quaife LSD setup and have a custom ring gear and pinion made instead of 3.07 found within the c32 diff.
anyone have any help to offer, any resource/person for me to contact?
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someday ill get my hands on star, but not sure i could learn how to use it! feel like i'd have to learn german to garner its full potential.
supercharger maybe someday if i got bored with the N/A. I really wanna squeeze everything i can out of it with cams, headers... and then before i screw with the heads and compression id make the choice whether or not to go forced or stay all natural
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So there's no way to even supply some directions w/o screenshots? (im assuming not, blacklisted is a word i equate with eff'ed)
does this mean that the diffs can be programed to the desired ratio?
OR
that our cars can be programed to support such differentials when replaced?
sorry for sounding naive C:

Now to find a developer mode.....
one of the SAs at the local dealer is a corvette tuner independently, maybe he'll sympathize and help me out. otherwise, im buying you a plane ticket brother.
if you figure out a way around your blacklist thing, via the way any dealer can do it, im definitely listening.
thank you special K!!
Called dealer. They can get access to developer if they need to. They call MB and get a password to enter that mode. The shop foreman said he had done this a couple of times in his 8 year history there, lol.
So I guess ideally we'd find the way to do this without developer, correct? If have access to developer, then what is the other part of star called that was blacklisted that you dont have access to? Is there a way to do the ratio change in your now 'blacklisted' mode? (sorry dont know what its called)
Ive got a PM out to Johnand maybe he has access to what you dont?
Ive also got a call out to the shop thats doing the gear swap. Hes checking with his partner if they know someone with star.
Good luck and take care
Good luck and take care
Thanks for the heads up. So this has to be coded directly to the TCU?
Edit: You think his manual will throw codes too?
Last edited by W203E35; Jan 20, 2011 at 06:48 AM.
I have no further details than what you gave me. But im hoping what you gave me is all i need
The dealer has never done this before and has no idea but said they would follow your screenshots in developer mode and see what happens.
I really need John to get back to me, ugh.
EDIT: John got back! Developer is the only mode where an option exists to change ratio! woohoo!
Last edited by cpbeasley; Jan 20, 2011 at 09:53 AM.
Good luck and take care
fortunately, my 6 spd manual doesn't have a trans controller, and last time I checked the only slipping inside a manual is from the clutch, so I dont share the worries you do with your auto-box.
Good luck to your efforts, however my 6 spd is ready to march on
fortunately, my 6 spd manual doesn't have a trans controller, and last time I checked the only slipping inside a manual is from the clutch, so I dont share the worries you do with your auto-box.
Good luck to your efforts, however my 6 spd is ready to march on




