Mobil 1 75W-90 - Page 2 - PeachParts Mercedes-Benz Forum

Hatterasguy · #16 02-04-2007, 12:44 PM

I second the above advice. When I first changed what I am sure was the orignal diff oil in the SDL it came out pretty clear actualy. But after a year of running Mobil 1 changed it again and it looked like crankcase oil!

Man that stuff cleans people are not kidding!

The only reason not to use synthetic be it Mobil 1, Amsoil, Redline is cost. Since the rear ends take so little and the change intervial is so long the cost point is mute. Use synthetic.

tobybul · #17 02-14-2007, 10:42 PM

All these fancy tests about syn vs min oil.... syn has proven itself to me over and over to lubricate and clean out deposits especially in engines. Although it may not appear to coat the gears in that website's test, how then can you explain a clean all-the-way-to-the-top and easy starting engine after syn is used in it. If syn doens't reach the top part, then that part of the engine would remain dirty - but its not. To me, this proves the efficiency of syn oil.

Matt L · #18 02-14-2007, 11:28 PM

Quote:

Originally Posted by lkchris

Mercedes has never approved synthetic oils for its differentials.

Are you sure about this? I recall reading that synthetic oil is now recommended for replacement in the 210. They say you can top up with synthetic, but it's better to replace it all due to the better fuel mileage.

babymog · #19 02-15-2007, 10:53 AM

The original differential photo looks very much like water in the lube. Check the vent when you change the fluid, happens a lot to guys in the LandRover group from water crossings etc., but old cars do get condensation in them. I had to dump 42pints from my Wanderlodge differential because it had condensation in it.

The bobistheoilguy website is, well, interesting. This particular "test" has been floating around internet sites for years and for some reason keeps resurfacing.

His test using oils and additives on small stamped gears with sharp corners run by a high-speed electric motor don't necessarily emulate real-world testing of 6" diameter bevel gears or bearing loads turning at lower RPM. Also does nothing to test the actual lubrication properties under any conditions. The latest test on his site "tests" several air filters, with the criteria for good/bad being the color of dirt deposited on a small patch of paper filter used as a secondary filter in his daily driver, photographed on a kitchen stovetop.

I commend him for his attempts, and likely he has good intentions, but IMO his testing has nothing to do with whether the oils or additives are of any value. I have no connection with any oils or additives, don't use Lucas additives, but would like to see only scientific tests and results, give this bob guys website the heave-ho.