Wheel bearing grease does three jobs: it keeps a film between the rollers and the race, it carries heat away, and it keeps water out. Get the grease wrong and a good bearing fails anyway. The good news is that you do not need a specialty product, just one that meets a few clear requirements.
The short answer
- Use a high-temperature wheel bearing grease made for the job, in the usual NLGI grade 2 consistency. Look for "wheel bearing" and a GC-LB rating on the label.
- Boat trailers: use a water-resistant marine grease. Warm hubs that get dunked draw water in.
- Disc brakes: the hubs run hotter, so the high-temperature rating matters more.
- Do not mix greases. Clean out all the old grease before you switch brands or types.
What to look for on the label
| Look for | Why it matters |
|---|---|
| "Wheel bearing" or "high temperature" | Brakes heat the hub. Grease that softens too much runs out of the bearing and past the seal. |
| NLGI grade 2 | The normal consistency for wheel bearings: firm enough to stay put, soft enough to reach the rollers. |
| NLGI GC-LB | The industry certification for wheel bearing and chassis grease. It is a quick sign the grease was tested for this job. |
| Water resistance / "marine" | Essential on boat trailers and useful on any trailer that sees rain, washes or creek crossings. |
| Rust and corrosion inhibitors | Protects the bearing while the trailer sits for months. |
Drum brakes vs disc brakes
Most RV and utility trailers have electric drum brakes, and a good high-temperature wheel bearing grease is right for them. Disc brakes put more heat into the hub, so on a disc-brake axle a high-temperature, disc-brake-rated wheel bearing grease is the safe choice. Our 10-inch Timken kit listing recommends disc-brake wheel bearing grease for repacking.
Boat trailers
A hot hub dunked in cold water pulls water in past the seal as it cools. Marine grease is made to resist washout, and it is worth using on any trailer that launches. Let hubs cool before backing in when you can, and inspect yearly regardless of miles. If you run spring-loaded bearing protectors, read our Bearing Buddy vs repack guide first: over-greasing through them forces grease past the inner seal onto the brakes.
Don't mix greases
Greases are made with different thickeners, and some do not get along. Mixed together they can soften and run, which leaves the bearing dry. When you switch greases:
- Wash the old grease out of the bearings and the hub with solvent.
- Let everything dry.
- Pack with the new grease, and use the same one from then on.
The same rule applies to grease-through (E-Z Lube) spindles: pump in the same grease that is already in the hub. See our grease-through axle guide.
How much grease
- Pack the bearing fully. Force grease into the wide side of the cage until it comes out of the narrow side, all the way around. A smear on the outside is not packing.
- Coat the races and the hub bore lightly.
- Do not fill the hub cavity solid. Extra grease has nowhere to go but past the seal.
Our Timken repack guide walks through it step by step.
Greases we stock
- Timken Premium Red Wheel Bearing Grease, 16 oz tub: a high-temperature wheel bearing grease in a tub, handy for hand-packing.
- Lucas Oil Marine Grease, 14 oz tubes (10-pack): an NLGI GC-LB certified calcium sulfonate grease for boat trailers and wet use.
- Lucas Oil Red "N" Tacky Grease, 14 oz tubes (10-pack): an NLGI #2, GC-LB certified tacky grease in grease-gun tubes, with strong water-washout resistance, for chassis and bearing work.
Bearings while you're in there
If the old grease is dark, gritty, milky with water, or smells burnt, inspect the bearings and races. Any pitting or blue heat marks means replacing the bearing and its race as a set.
- 3,500 lb axles (10-inch drums): Small Bearings, 10-inch Timken kit
- 5,200 to 7,000 lb axles (12-inch drums): Big Bearings, 12-inch Timken kit
Everything ships from Upland, California.