Will Rear Brake rotor overheating comprimise bearing grease?
 

Last week I got the rotors cherry hot on an 84 300cd from rear calipers sticking ,replaced pads ,calipers and master brake cylinder and everythings up to snuff. Now Im worried after overheating the rotors with the severe heat that the rear bearing grease might have melted away leaving the bearings somewhat dry ,has anyone experienced this issue. It looks like 2 special tools will be needed to get at these bearings .Anyway to supply grease without taking the axels out ? looks like a sealed bearing .

Is it making any noise that is unusual?

The rear bearings are sealed. While the grease may have been compromised due to overheating, unless you see leakage from around the backside of the trailing arm where the axles are inserted, I don't think you'd lose any...

Post your location and see if anyone has the castle socket to remove those.

Not yet ,just like to beat the chance of it going out while driving.Houston area.

wheel bearing grease would be OK as they are pretty much sealed, your big concern should be to replace the brake fluid.

I had this same failure on an '84 300D I owned a good while back. Although I was concerned about the wheel bearings, I never serviced them due to the inconvenience and specialized tools required. They lasted the remaining life of the car. IIRC, the "event" happened in 1995. I sold the car to a friend in 1999. He drove it until rust and a failed transmission took it off the road in 2004 or 2005? So the bearings lasted at least 100K miles, probably more.

Hope this will alleviate your worry. My 300D rear brake bind and overheated to the point the rubber dust cover caught fire. I put it out with a fire extinguisher.:mad: Bind at least 2 more times afterward. Replaced the MC and I have driven the car 4K miles since with no issue with rear bearing.

However, individual experience may be different. So it is your call at the end of the day.

Thanks for the replies ,I plan a trip to the hill country this August in the 300cd and hope to take some video while cruisen thru the canyons.

Yes, too much work to replace the Grease unless there is a know issue.

If you use the Factory Method; Silde Hammer to remove the Hub it damages the Bearings.
Then near the end of it if you over tighten it and the end play is too tight you get to start over and damage the Bearings again.