Trailer Grease - How Often?

[gibbywmu]

Hi All,

2018 Yacht Club Trailer/Jet Ski here, Michigan native, so never dumping in/out of salt water. I'd say I take mine in/out of the water at least 10-15 times a season. Typically I've been adding grease at the end of every year, just wondered if it was really necessary?

How often are you Northern States people changing/adding grease? Once a season?

I HATE my dust caps. I have the newest style Super Lube Hub where the zerc is on the rear of the hub, and it forces the old grease out the front. Problem is after taking the crappy aluminum dust caps on/off over the last 4 years, the fit isn't as good.....and the bad Michigan roads vibrate them out JUST enough so that an annoying amount of grease usually ends up all over the inside of the rims by the time I'm at my lake house 1:45 min away. Pain in the ass. So, I know there is plenty of grease in there.

My concern was just for water inside that grease. It's never looked water contaminated before, so I was curious as to how often others are changing/adding.

[K447]

The posted diagram shows a removable rubber plug in the center of the dust cap.

Is that what your wheel hubs have?

When you say you 'add grease' at the end of each summer, how much new grease are you pumping in/through the hub and bearings?

Are you seeing grease slung outwards from the rear grease seal onto the inner side of each trailer wheel?

[gibbywmu]

No,

I actually have aluminum dust caps. I'm pumping enough grease until I see the "new" grease start to come through the front just as you see in the diagram. Outside of the rim is where some grease ends up often. The grease that's coming out is because these aluminum dust caps have started to vibrate out from the bad roads. So after a 1:45 drive, there's enough a gap for the grease to make it's way through. I always have to take a 2x4 and bang that cap back in after a trip.

I'll attach more pics so you can see my caps. There's got to be a different solution than these crappy aluminum caps. As mentioned, longer road trips they are starting to come out, so all it takes is a small gap and that hot grease (that gets less viscous as it heats) finds its way out.

Maybe I'm just using too cheap of grease? Just a Wal-Mart brand (Super Tech maybe?), but it's in fact marine grade. Would never use anything but that for water applications.

But..........I'd still like to know how often everyone is changing their grease out. Is it really necessary to flush it out once per season.

[K447]

If the grease that is inside the hub bearings is not being contaminated with water or dirt, the grease can last for years.

The primary defense against water intrusion is the grease seal on the back side of the hub. It is not unusual for the rear side grease seal lip to become worn, especially if the hub shaft surface becomes corroded or roughened with use, where the seal lip rides on the metal axle. When the rear grease seal becomes compromised it tends to leak grease out the back, which then slings outward onto the wheel around the hub backside.

I use Bearing Buddies, which are 'big dust caps' that also apply a mild spring tension pressure onto the grease trapped inside the hub. With a good rear grease seal the pressure is not enough to force grease out past the seal. But it is enough positve grease pressure to resist water entering past the inner seal. Which keeps the grease from being contaminated, which means you do not have to change the grease.

If the rear grease seal begins to fail there may be grease oozing out the rear and you can see it accumulating on the wheel.

My Bearing buddy also have a 'grease level indicator' on the front side, so I can visually check whether a hub has been losing grease.

The Bearing Buddy is effectively a high grade dust cap. It is tapped into place like your existing dust caps but it is made from much better metal. There are regular versions and a stainless steel 'marine grade' version. For fresh water use the stainless steel version is probably not really necessary.

There are other brands of similar product to Bearing Buddy.

You can probably purchase the rubber insert type of dust caps to replace what you have now. No grease pressure feature, just a simple dust cap with rubber center. There are a few sizes of dust cap diameter with a very common size being 1.980" or very close. If you have a measuring caliper you can check what the ID is of your hub and buy the corresponding size.

Your current dust caps may be worn from repeated reinstallation and a new set would stay put.

[beaver6713]

Re pack and grease once a year. Grease is cheap, sitting broke down beside the road is not

[Team Bilford]

Re pack and grease once a year. Grease is cheap, sitting broke down beside the road is not

Use Bearing Buddies and you won't have to deal with water or packing your bearings.....for decades. I finally pulled mine apart after 19 years and there was no water and the bearings looked brand new.

[beaver6713]

Use Bearing Buddies and you won't have to deal with water or packing your bearings.....for decades. I finally pulled mine apart after 19 years and there was no water and the bearings looked brand new.

The water will still get in through the wheel seal, eventually. And, bearings do not last for decades, they will pit and need to be replaced. maintenance is cheap

[Team Bilford]

The water will still get in through the wheel seal, eventually. And, bearings do not last for decades, they will pit and need to be replaced. maintenance is cheap

You simply are incorrect. Please review other posts that discuss the operation and benefits of using Bearing Buddies.

[troyheb]

I usually only hit mine before long trips which is usually once or twice a year.

[Mr. GP1800]

As long as the grease isn’t water or dirt contaminated it’s fine. I pull trailers 10s of thousands of miles a year. No bearing problems. I just took my ski trailer to Florida and back a week ago. I’ll probably check out my bearings once the weather here doesn’t suck. But they are the original bearings that came with my 2013 Triton elite double trailer, and I’ve hauled this trailer all over the place. I bet I have 40,000 miles on the trailer. It’s going to need its second set of tires shortly too. I actually wear them out. The tread is getting a little thin

[K447]

You can install better quality dust caps.

I like the stainless steel version of the genuine Bearing Buddy. It think it would work just fine with your hub mounted Zerk version of Super Lube. Use the inner Zerk to pump through the fresh grease, then install the Bearing Buddy. Pump grease into the bearing Buddy until the grease indicator moves outwards.

It will slowly burp out the trapped air. During towing it will bleed out more air. Keep pumping more grease periodically into the Bearing Buddy until the indicator stays consistent over time.

With fresh grease and functional Bearing Buddy, the grease should last for years.

Note that Bearing Buddy creates a mild positive pressure on the grease inside the hub. The slightly pressurized grease prevents water from seeping in past the seals.

If the grease seal on the inside of the hub is worn or the shaft surface the seal rides on is not smooth then grease will ooze past the damaged seal. IF that happens install new seals and inspect the shaft sealing surfaces. A worn or rusted metal axle shaft surface can be repaired using a special thin stainless steel sleeve that slides onto the axle stub.

Hi All,

2018 Yacht Club Trailer/Jet Ski here, Michigan native, so never dumping in/out of salt water. I'd say I take mine in/out of the water at least 10-15 times a season. Typically I've been adding grease at the end of every year, just wondered if it was really necessary?

How often are you Northern States people changing/adding grease? Once a season?

I HATE my dust caps. I have the newest style Super Lube Hub where the zerc is on the rear of the hub, and it forces the old grease out the front. Problem is after taking the crappy aluminum dust caps on/off over the last 4 years, the fit isn't as good.....and the bad Michigan roads vibrate them out JUST enough so that an annoying amount of grease usually ends up all over the inside of the rims by the time I'm at my lake house 1:45 min away. Pain in the ass. So, I know there is plenty of grease in there.

My concern was just for water inside that grease. It's never looked water contaminated before, so I was curious as to how often others are changing/adding.