Sierra 18-9220-1 Calcium Sulfonate Marine Grease 14 oz

If you tow a boat or run gear that lives around salt water, the grease you pack matters more than most folks think. Sierra Marine's Hydro Defense heavy-duty grease uses a calcium sulfonate thickener, and that's really the whole point of this cartridge. Calcium sulfonate grease was built to stay put when water tries to wash it out, which is exactly the problem you fight on a trailer that gets dunked at the ramp every weekend.

Here's why the chemistry matters. A calcium sulfonate grease naturally resists water washout, stands up to heavy loads, and helps fight corrosion on the metal it's protecting. That combination is hard to beat around salt. A lot of ordinary greases will emulsify and run out of a bearing once water works its way in, and then you're staring at a smoking hub on the shoulder of the highway. This one is formulated to shrug that off and hold a film right where you need it, on the races and rollers that carry your load.

Where does it go? Trailer wheel bearings are the classic job. Pack your hubs with this before the season and you'll sleep a lot better on a long haul. It's also right at home on steering components, u-joints, winch gears, coupler and latch mechanisms, jack posts, and just about any grease fitting that sees water or takes a real load. Anglers running a single boat trailer, cruisers with a heavy tandem-axle rig, folks maintaining a lift, a dolly, or a set of rollers, all of them can put a cartridge like this to work. If your hubs run spring-loaded bearing protectors, this is the grease you top them off with too.

Heavy duty isn't just a label here. Calcium sulfonate greases carry genuine extreme-pressure and high-temperature capability, so the film doesn't break down when a bearing runs hot on a long tow or a fitting takes a shock load. That's the kind of margin you want on a part that's a pain to service and expensive to replace. And because it fights rust as well as it lubricates, it does double duty on a trailer that sits through a wet off-season, when corrosion, not wear, is what usually kills a neglected hub.

The format is about as simple as it gets. This is a single 14 ounce cartridge, the standard size that drops straight into a normal grease gun. No adapters, no odd fittings, no mess beyond the usual. Load it, prime the gun, and go. One cartridge will handle a bearing repack and still leave you plenty for touch-up shots through the season, so it's an easy thing to keep in the tow vehicle, the dock box, or on the shop shelf.

A quick word on doing it right. If you're switching over from a different grease, it's worth purging the old product out of the fitting or the hub first so you aren't mixing thickener types that don't always play nice together. Do that once, settle on one grease, and stick with it going forward. When you pump fresh grease into a fitting, keep going until clean grease pushes the old, water-stained stuff out the other side. Check your hubs for heat at every fuel stop on a long tow. A warm hub is normal, a hot one is a warning, and re-grease on whatever schedule your axle maker calls out.

Sierra has been supplying marine engine and rigging parts to boat builders and OEMs for decades, and their lubricants are held to the same standard as the rest of that catalog. For a part that quietly keeps your wheels turning and your gear moving, a cartridge of good calcium sulfonate grease is about the cheapest insurance you can buy.