Rear end ratio in my 92 300ce - PeachParts Mercedes-Benz Forum

#1 05-03-2002, 03:48 PM

My 92 300ce seems to be turning some serious rpm's.Its turning 3500 revs at about 72 mph. As far as I know the car has not been touched and is stock. I just sold a 92 300sl which, I understand,has the same engine. It seems to me that it wasn't wound up as much but I could be wrong. Does anyone know their gear ratios for this car and does this seem o.k.? vin WDBEA51E7NB668785

stevebfl · #2 05-03-2002, 06:55 PM

I don't know what rpm you should be doing but the ratio of the 300CE should be higher (less engine rpms) than the 300SL. The 300CE has a 3.06 ratio from 91 on. Up to 90 it was 3.27. The 300SL has a 3.69 ratio with the automatic and 3.46 with the 5spd. The 300SL has the 5spd auto which is odrive so it could wind up with the higher over all ratio. The TDM gives a 240kph max speed for the 129 and 232kph for the 124.051 car, so the overall ratio must be higher with the odrive tranny even with the much lower ratio diff.

#3 05-03-2002, 08:08 PM

Steve, If the rear end ratio is higher, it would give ''higher '' RPM for a given speed, not less as you mentionned. Probably a ''typo'' from your part, I guess.
JackD

Ashman · #4 05-03-2002, 11:12 PM

It definately should be 3.06

I was under my car today and the mechanic. It is imprinted int he differential housing on the right hand side at the bottom.

Alon

omegabenz · #5 05-04-2002, 03:28 AM

That doesn't seem too unreasonable if you have 3.07, I dont think that it is 3.06. If you can tell me the factory tire size for your car, what size you are running now, I can figure out which one it is if you care that much.

Also, if you want to know. Climb under your car and look at the rear differential. if you look on the bottom left hand corner (drivers side) you will find the gear ratios. Make sure you also arent in third gear.

At 60 mph, turning 2100 is 2.41 gear ratio if that helps any. Typically mesurements from 60mph are easier to tell if you are in final gear (drive)

Hope this helps,

Austin

Ashman · #6 05-04-2002, 03:59 AM

yeah 3.07 or 3.06 its one of those. I just took a quick glance at where mine was. I was too busy looking underneath at everything else..

Mine is usually around 2500 I think at 60 maybe a little more or less If I remember Correctly. Its been a few weeks since I drove my car since it is well undriveable at the moment.

Alon

stevebfl · #7 05-04-2002, 03:17 PM

Actually Jack, I said it right. Higher gear ratios produce less rpms. A 4.11 is considered a low gear ratio while 3.06 would be a high ratio. Its all a matter of semantics.