PeachParts Mercedes-Benz Forum - View Single Post - Switching diff to M-1 synthetic question

Jeremy5848 · #10 09-07-2007, 08:04 PM

I recommend wiping the inside bottom of the diff with a clean rag and some solvent, to remove as much crud as possible, then filling with Mobil-1 and drving normally. As has been suggested, a change after one year would be reasonable. The subsequent fill of M1 should be good for at least 30,000 miles after that.

With all of the axle changes I had to do recently, I ended up draining and filling my diff three times in a year. The inside looked cleaner each time. Even the original dino oil came out fairly clean the first time, over a year ago. The Mobil-1 that replaced it came out clean each time except for a little suspended crud that I removed with a coffee filter (a slow overnight process

).

Aside from being a better lubricant, the Mobil-1 has better cold-flow qualities, always nice to have in snow country. Although I no longer live in a cold climate (for which I daily thank God), I do occasionally visit one, and it's nice to do anything I can to make the old diesel run better.

Jeremy