Sounds like you're using a pneumatic grease gun. I'd be leery of using a pneumatic gun to grease my wheel bearings, as it's easy enough to overfill them with a manual gun and blow out the grease seals which means you'll need to tear down the hub to replace the seal. You'd be best served by taking the cautious route and filling the hubs manually. A product like the # ALL940798 you'd looked at would work perfectly. view full answer...