Differential questions!
 

Hi all!

The differential of my 190D 2.5 turbo has been bad (making noises) since the first day I bought it.

First it would do a "clunk" noise when changing from 4th to 5th gear (manual). Now it does it with all the gears.

My car is a '92 190D 2.5 turbo 5sp manual european (I live in europe). As far as I know it's a 2.65 ratio differential.

I'll start looking for a better differential, at least in a better condition than mine, at the junk yards.

Is there anyway I can tell what ration the differential has? I want at least a 2.65 one. What mercs used the 2.65 diff?

Also is there any difference between the diff froma car with abs than the one without abs?

If I can I'll try to find a lsd diff. How can I tell if a diff is lsd or not? Which mercs used them?

Thanks a lot!

Deni

A euro 2.5T with a manual has the 3.46 ratio. You probably shouldn't go any taller a ratio than that or your acceleration from a stop will be poor and you will prematurely wear out the clutch.

Don't automatically assume it's the differential at fault. Check your engine mounts, transmission mount, both flex disks, center support bearing, u-joint and rear suspension bushings before you condemn the differential. There are lots of wear items that can cause clunking during shifts.

Hi!

Thanks for the clarification! I did check and changed everything it had to. All the mechanics I've been to say it's the diff.

Our mechanics are ignorants, but they've seen a lot of mercs. I'd say in average we have more mercs/people than any other country.

How can I tell the difference between different diffs?

On the lower rear corner of the main body, where the back cover bolts to, there will be a stamp that shows the ratio.

If you change the ratio, you will need the speedometer from a car with the same ratio to keep the readings accurate.

mb differentials are fairly easy to rebuild. the parts are somewhat pricey here in america but maybe not where your located. you are much beter off with a rebuilt diff then a used one.

Are the differentials from the w201 interchangeable with the differentials from the w124 chassis?

Also how can I tell the difference between a lsd and non lsd diff?

I would look closely at the flex donuts in the driveshaft and the half shaft/ cv joints. The diff is a very very robust unit in a benz that is pretty hard to wear out.

Generally with a diff if you lift the back of the car off the ground and turn one wheel, if the other goes the opposite direction you have an open diff. If they both turn the same way it is a limited slip.

Tom W

Very good advice. I bought a near mint 300D that PO insisted was a bad trans. only to find a bad half shaft........OH HAPPY DAY:D