[W126 Coupe] Help! : diff ratio's

[Satish Tummala]

Also, there is the 1.4 liter unit used in 12 cylinder models

-----Original Message-----
From: "Steve Nervig" <dakota at mac.com>
To: "Mercedes Coupes Mailing Lists" <mbcoupes at mbcoupes.com>
Sent: 4/29/07 9:18 AM
Subject: Re: [W126 Coupe] Help! : diff ratio's

Alex, first off, let me say that I am not an MB diff expert, so  
verifying what I say would be a good thing.

My understanding is that MB has generally had two sizes of  
differential housings and gears. There is a smaller size (1.0 or 1.1  
liter oil capacity, 185 mm dia ring (crown) gear) and a larger size  
(1.3 liter oil capacity, 210 mm dia ring gear). There also appears to  
be some changes within these two categories. See Job 35-500 for some  
visual clues on differences.

My belief is that the two sizes are not interchangable as a unit in a  
particular chassis because of mounting configurations and that the  
gears are not interchangeable between housing sizes.

I've heard that the smaller size generally came on cars with less  
than 200 HP and the larger size on cars over 200 HP.

I've also been told that changing or installing a gear set in a  
housing requires a special tool jig set and can't be done properly  
without it. In the past, I've set up rear ends (non-MB) with shims  
and machinist blue, but apparently this isn't how an MB rear end is  
set up. Something about crush washers on the pinions seals. How an  
improper set up would manifest itself, I do not know. Maybe you could  
get by with it for limited racing, and the only problem would be a  
leaky pinion seal. Maybe not.

So apparently, the trick is to find a suitable donor car that has the  
same configuration housing and replacing the whole thing, without  
opening up/changing the gears.

I'm sure there is someone who can either confirm or poke holes in the  
above statements.

Regards,
Steve Nervig


On Apr 29, 2007, at 3:54 AM, Divov wrote:


> This website is just great!  Without it I would be floundering  

> around in the dark.

> Thanks to the various inputs, I have located a 3:46 diff from a 80  

> 350SE saloon and the best of it is that it is available free,  

> gratis & for nothing!!

> Now, what I am scheming is the following:

>