Grease on electric trailer brake magnets

[Luke'sScreenName]

Lippart, who made the axle/hubs/brakes says if excess grease gets on the magnet you need to replace the entire brake assembly. What say ye? And how do I keep this from happening again?

 

[flyerdan]

I can't see how grease would effect an electromagnet, the brake shoe materiel, yes. I don't know a lot about electric trailer brakes, but I'd imagine that the only way grease could get in there would be from a rear hub seal or excess grease on the pivot points. Use sparing amounts of high temp brake grease on the points that need a bit of lube and make sure that the seal is good, and also the correct size. I took a hub off a motorhome once that had a seal with a center hole about a quarter inch bigger diameter than the spindle it was on, so it didn't do much good. Also, if it has bearing buddy caps on it, don't fill them until you're out of spring, that puts unneeded pressure on the seal.

 

[BobG_in_VA]

I understand if you have the hubs that have grease zerks built into them if you pump too much grease into the bearings, the inner grease seal may get pushed out and grease will get on the brakes/shoes. I know I never pumped more than a couple a times on the gun on each hub, and only did that a couple of times a year. BobG in VA

 

[mikesee]

I'd clean all the grease up with solvent and put it back together and see what happens. Figure out why grease got in there in the first place and solve that.

 

[woody]

I wonder if this is what is happened to my new trailer, I have two other trailers with electric brakes and when empty and the brake controller set on five I can press the button and slide the tires in my gravel driveway I do that just to check them before I go and load up what ever I am going to haul but this new trailer I have will not do it even with the controller set to ten. I adjusted the brakes and the builder adjusted them and he also found one wheel connected wrong so they work better but not as well as the other trailers. when I get the time I will pull the wheels and look for grease.

 

[BeezFun]

If the brakes are used a lot, like coming down a mountain, it can heat the axle up so much that the grease runs into the drum and contaminates the lining. It can also happen if a brake is dragging. There's no reason to replace the magnet, it's a piece of steel. The shoe material would be ruined if grease got on it.

 

[Luke'sScreenName]

It's a new to me trailer so I don't know what the mechanism was. Though I suspect too much grease was forced in the easy lube hub.

If I do replace the assemblies (all four) should I go aftermarket for about $180 or Lippart brand for $250?

 

[mikesee]

I would suggest jacking up the trailer and testing all the brakes. Pull the break away pin and check each axle then do the same from the brake controller. Replace as necessary. I have had good purchasing experiences with easternmarine.com trailer parts

 

[skipmarcy]

The grease on the magnet will decrease the friction of it against the drum when energized and decrease the braking effect. When energized, the magnet attracts to the heavy, flat surface inside the drum which causes the magnet to cam the brake shoes into action. If the magnet is slipping easier on the drum due to grease it won't cam as hard against the shoes. Simply clean the grease off the magnet & drum and find out where it came from and repair that issue. If grease got on the shoes, they cannot be cleaned properly and need to be replaced. Personally I think those "bearing buddies" are more trouble than they are worth - there's no need to grease wheel bearings that much. If properly sealed, wheel bearings only need to be serviced every 20 - 30k miles just like on cars & trucks. The only place the bearing buddies are helpful are on boat trailers that get in water and don't have brakes ...

 

[dieselcrawler]

Having maintained nearly a dozen car hauler type trailers at work for the past year and a half, I agree... skip the bearing buddy grease fitting type caps. A properly packed and adjusted wheel bearing will be fine, in most cases, even under harsh conditions. Our trailers are used daily, often overloaded, drug around on rough country roads and access roads to gas wells and right of way jobs... only one has had a bearing get rough to the point we replaced it, but several needed brakes due to over greasing, while the ones without zerk fittings fair the best. We service them about every 6 months, unless in the shop for other issues. "Service" them, pull the wheels, hubs, check and replace/adjust brakes as needed, check lights, safety chains, etc.