I noticed that the front hubs on my 5a had accumulated moisture on the hub face. It's not so much that I think there is a real problem. Probably just long term leakage from the plug. The oil levels are okay, but I could fit a little more in it. Does anyone know what gear oil to top it off with? Should I just pour it in the plug hole or squirt it into the 3/8th hole on the inside?
I use Lucas hub oil. It's the right stuff for wheel bearings, and is very viscous so it doesn't seep out. The 3/9" plug is a drain hole. I just take the rubber plug out to add oil, but the plug would work fine if it was on the "up" side.
Brian
Plugs can harden and dry over time and cause oil migration. If they are old, maybe they could need replacing.
Thanks for the info. My manual seems deficient on this subject, although it looks like it is saying to use a GL2 lube. Mine does not have a small drain plug that I can see-- just the larger end plug itself, which is probably a bit dried out.
Fresh plugs are available at the parts jobber near you.
Take one with you as a sample.
Fresh plugs on an old wheel end communicates a potentially positive message about underlying preventive maintenance to those who have an enforcement style eye...
happy coaching!
buswarrior
BE AWARE that the transparent window that the plug fits into is kind of a unique size for MCI's. It took a lot of looking to find a pair when I broke one taking the old hardened plug out of the hub cover on my MC-5C. After a lot of looking I found a part number, then after a lot of calling I found two (only two!) units on a shelf in a truck store in Detroit, they would not ship and I had to call my sister to go get them. In the odd coincidence dept. I called her, and explained my issue and gave her the address, she said she drove past that store twice a day on her way to work...
Anyway, be careful with the plug and don't break the plastic bit it goes into.
Brian