Rear end replacement for a 280 SL... How to find correct one

[BaronYoungman]

I have read the archives and I see alot on the 230SL replacement, but because my 1971 auto rear end is leaking like a sieve from the boot(sleeve) and I am gonna have to take it apart and while I am at it........  I understand that there are certain 1971-1972 body 111 rear ends that will bolt up and give me lower rpms at highway speed.  How do I find these and are there certain markings on them that I need to find.

Thanks, Bob
(630) 903-9877

[jeffc280sl]

Hi Bob,

Can't speak to the W111 rear axle but I can recommend changing to a 3,27 ratio rear axle from the W108 4.5.  There is a wealth of information if you search on 3.27 or 3,27.

[ja17]

Hello Bob,

Yes, Jeff is correct, the 3.27 ratio comes out of a W108 280SE 4.5 sedan.  You may want to go to the video section of this site and see the vedeo by Dick Metzer on the subject.

[JimVillers]

I would like to add my impressions.   I have a 5-speed 230SL with a 4.08:1 rear axle.  I installed a European 230SL axle with a 3.75:1 ratio.  With my 5-speed, This feels like it is about a perfect ratio.  In fifth gear (0.8:1), the equivalent ration would be about a 3.00:1.  I have since put on my CLK 16 inch rims with 205/65/16 tires that I used on my 190SL last year.  The larger tires reduced the ratio by an additional 4.7% so the equivalent fifth gear (0.8:1) ratio would be 2.86:1.   This feels like too tall a ratio as I spend a lot of time in third gear around town. 

With a four speed transmission, I would think that replacing the stock 3.92:1 with a 3.69:1 axle ration would be a good compromise.  While the 3.27 would be excellent on the highway, it might be a little tall for city driving.

I will add that I have not driven a 113 four speed or a 113 automatic or any car with a 3.69:1 rear axle so take my comments as supposition.