Bearing Preload/Castle Nut Adjustment Question

[Calbar]

If the wheel rocks enough to hear it as you said I would lean towards tightening it enough to get the cutter pin lined up. I think a little tight is better than too loose.

This is incorrect. It is not supposed to be tight, not even a little. It is better a bit loose than a bit tight. Tight will generate heat and cause bearing failure.

Rob

[JessJoe4168]

Thank you el Rojo, i do intend to order an infrared gun prior to our next trip to monitor hub/brake temps at each stop, any recommendations?

I will also have a new TMS installed for that trip as I've having metal valve stems installed when the new Goodyear Endurance tires are mounted on the new 16" wheels.

Best regards,

Keith

I check the hubs, brake drum and tire sidewall close to the valve stem..
As mentioned --- you are looking for +10% variation.
Mid-day is best to avoid solar heat gain.

[Johnnyd53]

Let it wobble off, maybe you can help him put back on.

[huntindog]

Let it wobble off, maybe you can help him put back on.

Bearings NEED to have freeplay when cold. They are designed to run at zero clearance when hot. If you set them at zero clearance cold, then they will be too tight from expansion when hot. This will cause them to fail. There are two ways to set the cold clearance. 1. follow the nut tightening, loosening procedure in the manual precisely (do NOT second guess the manual by judging them to be loose and retightening them) 2. Use a dial caliper to measure the end play and set it to the specification in the manual. BTW, all tapered bearings in wheel applications are to be set this way. It isn't just a trailer procedure.

[Jamaddog]

Try swapping the nut from the one that lines up with the one that seams to be too loose. When nuts are threaded the threads start at different points.

[minnow101]

On another note; have you checked to make sure the 16” wheels won’t hit the underside of the wheel well? I know on my ‘15 27RL, no way a 16” would fit without a frame lift.

[DECelt]

Hello Fellow Grand Design Owners,

I'm currently in the process of replacing the severely greased brakes on our 2017 303 RLS which has < 3,000 miles on the trailer. I'm replacing the complete backing plate/brake assembly, hubs and upgrading to 16" wheels and Goodyear Endurance tires during the process.

Yesterday I replaced the brakes/hubs on the Left Front (Drivers) side and today I replaced the Left Rear (Drivers) side. When installing the new hub with new bearings/races I followed the procedure in the Lippert brake/axle manuals by torqueing the Castel Nut to 50 ft-lbs while rotating the wheel, backing off to remove the torque then hand tightening before installing the cotter key.

The Left Rear preload/castle nut adjustment went perfect, after following the procedure the cotter key hole was lined up perfectly with a slot in the nut after the hand tightening step. This provided just the right amount of runout for when the bearing expanding upon heating.

However, my issue is with the Left Front hub. Again I followed the procedure in the Lipper manual exactly. After hand tightening the Castel Nut the cotter key hole was not lined up with a slot in the nut. The Lippert procedure say to back the nut off just enough to line up the cotter pin hole. When I follow this procedure the runout seems excessive to me. Probably 1/16" or maybe just a bit more that that amount. End play can be felt when gripping the wheel on the edges and rocking it back and forth. You can hear a slight knock when rocking the wheel back and forth. This just seems too loose to me.

Thus the reason for my message. What would you do, should I

1) look for a washer shim to take up a bit of the space behind the Castle Nut with the nut pinned per the Lipper procedure or
2) tighten the Castle Nut just a bit past hand tight to enable me to line up the cotter pin hole with a slot in the nut that takes up the excessive runout.

FYI, when I removed the hub as installed by Lippert/Grand Design the Castle Nut was not loose on the axle spindle, I had to use Channel Locks to loosen it after removing the Cotter Pin. This makes me think the factory had the same issue with this axle spindle and implemented Option 2 above.

One other question pertaining to the Self-Adjusting Brakes. The Lipper Manual says to pre-adjust the brakes by expanding them against the hub until it is difficult to rotated the wheel, then rotate the starwheel in the opposite direction until the wheel turns freely with slight lining drag.

What is the purpose of this step, is to to center the brake linings within the hub and to minimize the number of adjustments the self-adjusters have to make to set the brake linings at optimum spacing? How much do you guys back off the starwheel after adjusting the linings against the inside of the hub.

Thanks in advance for your feedback!

Best regards,

Keith

Just a point of consideration. When you repacked the wheel bearings, did you use red permatex rtv sealant around the edge of the new inner seals? Dexter has been recommending this in their bearing repacking videos for some time. It may well be in response to greased brake issues like you had. There is also a school of thought that this issue occurs when you use the ez lube feature (if you have this?) This little extra step may prevent you from having another greased brake issue.

[gsitexas]

On another note; have you checked to make sure the 16” wheels won’t hit the underside of the wheel well? I know on my ‘15 27RL, no way a 16” would fit without a frame lift.

Thank you minnow101, my 2017 303 RLS has the 2" frame mod that Grand Design started putting on the 303 RLS in 2017. This model is now provided from the factory with 16" wheels/tires.

I read all I could on the subject and the consensus is if you have the 2" frame lift mod you are good to go for 16" wheels/tires.

I confirmed the 2" lift and also checked and confirmed that I had 4" + of clearance between the top of the 15" tire and the underside of the wheel well.

Best regards,

Keith

[gsitexas]

Just a point of consideration. When you repacked the wheel bearings, did you use red permatex rtv sealant around the edge of the new inner seals? Dexter has been recommending this in their bearing repacking videos for some time. It may well be in response to greased brake issues like you had. There is also a school of thought that this issue occurs when you use the ez lube feature (if you have this?) This little extra step may prevent you from having another greased brake issue.

Thank you DECelt, I used a high quality National (Federal Mogul) oil seal, Part Number 412920. This oil seal appears to have a red coating on the rim of it where it it contacts the inside of the hub. For this reason I did not use the red Permatex RTV sealant around the edge of the new oil seal.

I do not not believe the lack of RTV sealant on the factory oil seals resulted in the greased brake issues, all of my original oil seals were still in place within the hub, however, every spindle has two black rings of seal lip material around the circumference of each spindle.

My camper may be four years old but it has only been used for 10 trips ranging in 50-150 miles round trip thus with including the trip from the factory to Texas my camper has ~ 2000 miles on it. The brakes on all four wheels were totally soaked with grease to the point it was running out of the hub and all over the wheel surface.

I'm convinced the greased brake issue on my 5th wheel resulted from the use of very poor quality OEM grease and questionable installation procedures that were being used at Lippert at the time the chassis for the 5th wheel was manufactured.

Best regards,

Keith

[Buckskin]

Here is what happens if castle nut is too tight. You squeeze all grease from between roller bearings and bearing race. Therefore roller bearings are riding on bearing race without any lubrication and generates heats - metal to metal. You soon have bearing failure, better to be loose than tight.
Here is how I do it and it's worked for me for many years. Tighten castle nut up slightly tight with pliers and turn hub about dozen times to make sure everything is seated properly. Then back off castle nut and by hand slightly tighten and then back off just a very little bit, maybe 2 or 3 minutes if your looking at clock face.

Much better to be loose than tight, but not too loose.

Better to repack bearing on warm day rather that cold day; grease moves much easier. It's much easier to squeeze old grease from between roller bearing and bearing cage. Easier to wipe away old grease also. Also just enough grease is much better than excessive grease that may find it's way to brakes. Those zerk grease fittings on hub, I never use these. You may push grease pass rear seal and onto brakes, this happened to me once - learn from my mistake and don't use them..