Our safety on the road is a big concern, so I’ve always made sure to have my trailers wheel bearings and brakes inspected and maintained. Over the years I’ve relied on the Keystone dealer where we bought our Cougar fifth wheel to perform the task. Every two years I’ve had them repack the grease, replace the seals and inspect the bearings and brakes.
However this time I’ve decided to learn how to perform the required maintenance myself. Not only will it save me a fair chunk of money I feel I will benefit from knowing exactly how my trailers wheel bearings, brakes, and axles operate. Furthermore, if we ever suffer a breakdown on the road, I stand a good chance of fixing the problem myself. A handy skill to have considering the cost and hassle of getting an RV service center to do the work.
Disclaimer: I’m not a certified RV technician or mechanic. I’m merely an owner doing their own maintenance and sharing my experience doing that. This post and videos are provided for entertainment purposes and should not be taken as instructional. Do your own research and follow the manufactures procedures and manuals. I accept no liability if you copy anything I’ve done. You have been warned – Ray
Inspecting the Trailer Bearings and Brakes
The first task was to jack up the trailer and pull the wheels to get a good look at the condition of my wheel bearings, hubs, and brakes. I did this by removing one wheel at a time. I placed the jack under the axle near the wheel and under one of the suspensions U-clamps. A few inches of jacking lifted the wheel enough to remove; then I let off on the jack a bit to remove tension from the leaf springs.
Note: This way of jacking is not advised by the axle manufacturer (Dexter) or my trailer manufacturer (Keystone). They recommend using the trailer frame I-beam frame rails.
However, I feel it’s less risky doing it my way versus their recommended way by jacking on frame rails. These rails sit awfully high on my fifth wheel, and I would be jacking the whole side of the trailer up in the air versus one axle only a few inches. The risk is bending the axle, but I think it’s worth it for the increase in safety. Also, I’ve watched tire shops use the same jacking location under the U-clamp many times now when they are changing my trailer tires. I want to be clear though it is considered a no-no by some folks.
Once the wheel was off the next task was to remove the trailer hubs dust cap. I find the easiest way to get it off is with a rubber mallet striking the side of the cap at an angle. Next, there is a retaining clip holding the axle nut in place (Some axles use a cotter pin). Unscrew the axle nut, remove D washer and pull the hub slightly forward to remove the outer bearing. Then slide the brake drum off the spindle exposing the electric trailer brake assembly. Finally, with a seal puller, I removed the rear bearing seal and inner bearings.
The old grease needed to be cleaned off. A messy job for sure, so I had plenty of rags on hand and some brake cleaner spray. I wiped all the grease off the bearings, hub, spindle, etc. and sprayed off the brake surfaces. Once everything was clean, I could carefully inspect it for damage and/or excessive wear.
Upon thorough inspection, I decided both the bearings and brakes were due to be replaced. After 7+ years and over 60,000 miles, things showed a lot of wear. Many of the roller bearing surfaces showed signs of pitting and the brakes pads had very little life left in them.
Parts and Tools for the Job
The first step was to identify and round up all the parts for the job. I needed new bearings, races, seals and brake assemblies for each of my four trailer wheels. Thankfully my hubs, brake drum, and axle spindles still looked to be in great shape. Races or sometimes referred to as cups are a thin metal band of hardened steel that the bearings ride in. They need to be replaced anytime the bearings get replaced.
I located the official Dexter axle service manual online which was a valuable source of information and part numbers. I was also able to find some part numbers on the parts themselves. I decided to replace the bearings, races, and seals with quality Timken brand parts. For the brake assemblies, I sourced Dexter OEM replacements. I found the brake assemblies locally and ordered the other pieces from SummitRacing.com. Below you’ll see linked alternate sources such as Amazon and Etrailer.
Dexter EZ-Lube Axle – D44 (4400 lbs)
Dexter Brake Assembly Part Numbers
Bearing, Races and Seal Part Numbers
Hub and Drum Kit Part Number
Next was to acquire the right tools and supplies for the job. Many of them I already owned. However, I did purchase a few specialized tools to help with the task. I find appropriate tools make a job go much smoother. Heck, I was saving a bunch of money by doing the work so may as well treat myself.
Visit the Love Your RV! Amazon Page where I’ve put together a special category for Trailer Bearing and Brake Service parts/supplies.
Tool and Supply List:
- Lucas X-tra Heavy Duty Grease
- Bearing packing tool
- Grease gun
- Brake cleaner spray
- Anti-seize lubricant for nuts and bolts
- 20-ton bottle jack
- Race and Seal driver kit
- 1 1/2 inch socket
- Cordless 1/2″ drive impact wrench
- 1/2″ drive 0-250 ft/lbs torque wrench
- Socket and ratchet set
- 2 1/2 lb sledgehammer
- Brass drift punch
- Rubber mallet
- Brake spoon adjuster tool
- Seal puller
- Wire strippers/crimpers
- Butt connectors (waterproof and shrinkable)
- Butane Torch
- Shop rags
- Shop towels
- Nitrile gloves
- Fast Orange hand cleaner
Trailer Brake and Bearing Installation (Step by Step)
Steps to Replace Brakes and Bearings
- Lift axle under U-clamp using 20-ton bottle jack and remove the wheel
- Remove hub dust cover with a rubber mallet
- Remove axle nut retaining clip and unscrew the nut
- Slide the brake drum forward and remove the D washer and outer bearing
- Remove the brake drum from axle spindle
- Wipe off all the old grease and clean brake drum
- Undo the 4 – 11/16ths inch bolts holding the brake assembly on the axle
- Cut the pair for electric brake power wires and remove the assembly
- Install new brake assembly (There are left and right-hand pairs)
- Add anti-seize compound and torque nuts to 45-70 ft/lbs
- Crimp wires with butt connectors and shrink with heat
- Tape wires and dress leads away from the wheel
- Remove bearing races from the hub with a brass drift punch
- Clean out the inside hub surfaces and lube slightly
- Install new races with race driver tool
- Add a light coating of grease inside the hub
- Pack bearings with grease and install into races
- Drive in new axle seal using race driver disc
- Lightly coat spindle with grease and mount the drum
- Add the D washer and axle nut
- Preload axle nut to 50 ft/lbs while spinning the hub
- Release nut torque while holding hub stationary
- Finger tighten axle nut and back off slightly and install the retainer clip
- Check hub play – should have slight movement in and out
- Coat axle end with grease and install the dust cover
- Adjust brake shoes with brake spoon tool for slight drag
- Reinstall wheel and lower jack
- Torque wheel in star pattern 20-25, 50-60, and 100-120 ft/lbs
Well there you have it, that’s how I went about replacing the bearings and brakes on my Keystone Cougar fifth wheel trailer. Like I said I’m no expert just an owner wanting to learn to do his own maintenance and repairs. If you spot anything wrong here, feel free to contact me or leave a comment on the YouTube video and I will update the article.
I plan to take the trailer out for short test drives and will be monitoring the axle temperatures via my EEZRV TPMS when underway and with an infra-red temp gun at stops. I’ll also be checking the lug nut and brake nut torque after 30 miles and 100 miles. New trailer brakes will get adjusted after 200 miles.