Bearing lubrication: re-packing the hub?

[Phil Waterman]

Hi Hanno & Alex

Good question and point about repacking the front steer drive ball and hub. When I'm working with a clean one for a complete repack I go with the amount listed in the manual or drivers hand book which for C60S - C60L as being 4.5 lbs of wheel bearing grease (listed in capacities section) while in the Handbook it says 2.5 lbs each. So much for clarity.

Now as to over greasing my long term driving experience with my HUP is that the outer grease seal is stronger than the axle side so that if too much grease is pushed in over time it goes in the axle tube and just sits there.

I add 5-10 squirts of wheel bearing grease into the center of the ball each spring. See http://canadianmilitarypattern.com/Tools.html about half way down the page for how. This can be done through the plug hole on the ball. I like this method of put a little new grease in each year because it gets the new grease into the center of the steering balls.

Cheers Phil

[rob love]

Grease does not flow around like oil. You pack the bearings with grease, but in the cavities and on the spindles, you only have to put enough grease to prevent surface rusting from any condensate that might form. In other words, just smear a thin coat on the surfaces. There is no reason to fill the cavities with great globs of grease. While grease will not flow like oil, it will spin centrifugally. As a result, overpacking can result in blown wheel seals, and contamination of the brakes. The heat will not transfer through grease, and it can turn to a liquid.

I have seen some bad results from certain aircraft lubricants. A plane really only does short distances at high speeds, so that is not really relevant to a CMP. My own recommendation is to use a good quality automotive synthetic grease. They are usually very temperature stable (important to those of us on the prairies) and are good from -50° to somewhere in the 200°C range.

In the military, we used to use a GAA (grease automotive artillery) which was very old spec grease. Around 1990 we went to a synthetic mil spec (MIL-PRF-10924) grease which totally changed my mind re military grease. It strongly resists mixture with water (including salt water), does not turn rock hard in the winter, and does not leak all over the place on a hot day.

At the Shilo museum, that is the only grease I am currently using, which is especially important on a vehicle that may not be re-opened for another 20 years. I just recently had to replace some wheel cylinders on a chev 15cwt that I had rebuilt back in 1996. The bearings and seals were still in perfect condition, and I did not even have to touch them other than to re-adjust the rears on re-assembly.