oliverdog

Rockwell (Now Meritor) built some pretty stout and trouble free differentials for the trucking industry. When I was with Ryder we simply drained out the OE stuff and put in synthetic with no issues that I can recall. Thousands of single and tandem tractors were done and I'm sure the change had the blessing from Rockwell. There might be an issue with a limited slip differential as it may require a specialized lube formula.