Greasing

[kodiak545]

When greasing the axles, the manual says to use a hand grease gun

Just wondering why you cannot use a pneumatic (air) grease gun
Turning down the air pressure a little should work, force that grease into those bearings.

Any thoughts

[JRTJH]

What you're about to get into is the "theory" that if it doesn't fit, get a bigger hammer, or if a little is good, a lot is better.....

Not true with trailer EZ-lube axles. You're correct, you want to force grease through the bearings, but the "weakest link" is the grease seal on the back of the hub assembly. If you put too much pressure (or volume) behind the bearings as it's trying to "ooze" through the spaces in the bearings, you'll push the grease out the grease seal. Once you deform the seal or deposit grease on the back of the hub, you're setting yourself up for water intrusion and/or slinging grease on the brake shoes/drum. Then you're going to have problems.....

There is a caution in the procedure to use a hand pump grease gun (LOW PRESSURE/LOW VOLUME) and SLOWLY pump grease into the fitting while rotating the hub assembly. Rotating the hub allows the grease behind the bearing to contact all the surfaces and "ooze" through all the spaces, not just the "convenient ones" along where the grease is flowing. Going slow with a hand pump will save your grease seals and possibly your brakes..... I wouldn't advise using a pneumatic gun and turning down the pressure because you still aren't controlling the volume.

The concept of "force that grease into those bearings" will do more harm than good...... A lot of "tender loving care" will protect the grease seals much more than brute force with a bigger hammer (or in this case, grease gun).....



Just my opinion......

[outwest]

Plus, with a hand operated grease gun you can feel if there's too much resistance and stop before you blow the seal. If there is any mud on the zerk it can impede the outflow of grease, causing you to blow the seal.