I spotted a tiny leek from the diff on my 1988 240glt auto 230E and decided to replace the oil. I guess it has not been done in at least 10 years 70,000 miles.

I bought GL4 by mistake and noticed only after draining - so I shall use that as a flush for a few days at low speeds before repeating the job...

The Question!

How can I tell if this diff has LIMITED SLIP or not and which is therefore the best oil to use.

Any advice gladlly received. Thanks...

Andy

Well, I believe you jack the diff off the ground and put the trans in neutral and spin one wheel. If the other turns in the same direction then you have a diff lock. If the other wheel does not turn or goes in reverse then it's a standard planetary diff.
Hope this helps -T2P

Cheers TypeII, that is really useful - as it's dry this morning, I'll jack the old brick up and try it... Have you any views on oil types, or is it all a bit faddy?

Just 80w90 in a standard diff and LSD lube in a posi. I don't go for anything fancy if you're changing it enough. Every 70K is pretty good but every 50K is better if you know what I mean...
enjoy the good weather -T

lovely sunny day, so I didn't delay - flushed old (new gl4) oil out and refilled with good quality gl5 sae90, so I'm feeling saintly!

took the trouble to check rear axle, brakes, bearings etc. whilst the brick was up on the axle stands.

do you have a view on repacking bearings with grease? I did it about 4 years (16,000 miles) ago?...