Problem with Adjusting Lippert Forward Self Adjusting Brakes

Question:

I have a 36 ft-long 5th wheel RV with Lippert 7000 pound axles and the TV is a 2016 RAM 3500. In early 2020 I installed new Lippert backer plates with Lippert forward self adjusting brakes and new Lippert hubs as well. All year I had no trouble with braking or anything heating up above 30-35 degrees above ambient air temperature. I have traveled about 7,000 miles with the new hubs and self adjusting brakes. This year when I repacked the bearings, I noticed that the small race on one hub would spin as I was cleaning the old grease out. So I proceeded to replace all the new hubs 1 year old with the original hubs which have about 27,000 miles on them. Now my brakes will not engage to stop the trailer and TV when driving. I have about 3.15 amps at each hub when the truck foot pedal is applied and about 2.6 amps when I manually engage the brake controller. Also I jacked each wheel of the the ground and manually adjusted the brakes at each wheel using the star adjuster and the magnet stops each wheel from spinning when the TV brake pedal is applied. This year I noticed that I can spin the star wheels at each wheel, from the rear of the hub without raising up the metal curved plate covering the star wheel. When I initially installed the new hubs and backer plates last year I had to use one screwdriver to lift the curved plate over the star wheel and another screwdriver to turn the star wheel. QUESTION: What could my problem be? Thank you so much in advance.

asked by: Greg A

Helpful Expert Reply:

As we do not carry the Lippert brakes, I cannot say for sure what is going on as I have not had the chance to mess with them before. However, if you had say an etrailer.com Left Hand Self-Adjusting Electric Trailer Brake Assembly # AKEBRK-7L-SA, I would say it is most likely one of two things.

First, something has become disconnected on the brake. This does happen every now and then and can be confirmed by removing the hub/drum. If this has happened, you can most likely just reattach the pieces. But, if there is another issue, it could have also caused this to happen.

What could cause another issue is the older hubs being a bit wider in diameter than the new ones. This could then cause the brakes to over adjust when being used. This can cause the previous issue and I think may be what's going on. This will also require the removal of one of the hub/drums as you will need to compare the inside diameter of both the new and old drums.

If the old ones are larger, you will need to replace them with the new ones once repaired. This should get you back up and running properly. If it does not, or if they are measuring the same and nothing has come undone, your best bet will be to contact Lippert. They will have more insight and should be able to get you taken care of.

expert reply by: Lazer S