Tackling Bearings (Lessons Along the Way)

[howson]

Adding to my own thread as I'm now 1/2 way through doing the bearings (and brakes) again. For new readers that may be seeing this for the first time, my '19 315RLTS suspension is a MORRyde IS and it has Kodiak disc brakes.

FYI, the last service was 22 Feb 22 (27,661 tow miles on trailer at that time). Today is 29 Nov 23 and total mileage is 41732 (so 14,071 miles since last service).

The street side inspection and service is complete. Bearings and races look and feel perfect--no issues.

Gee whiz info:

• The MasterPro 412920 seal (O'Reilly Auto Parts) is a relabeled Timken 412920 (referenced in post 29). See https://cad.timken.com/item/seals/oil-seals-inch/412920
• A cross-reference of part numbers to the original Dexter 010-036-00 is here: https://www.trailerparts4u.com/files...hart_11-11.pdf
• The installation direction of the MasterPro is not obvious (to me). On one side there’s a slight raised rubber lip. This side goes on the AXLE side. The other side of the seal the rubber is slightly indented. That side goes against the bearing.
  • Direction of installation verified with Timken customer support.

For those who may remember the problem I had with the Caliper Guide Pins "frozen", I found that this time they were moving freely. (Yea!) Unfortunately there is still more wear on the outboard pad than the inner pad. :(




According to the box the new pads came in, there's two potential issues going on with the brakes (annotated below the pic below).



There's definitely a "Step in lining" issue with the outboard pad. I've already replaced all the hardware (last service), so that's not the issue.

The other issue is the "Only one side worn" issue. At this point it appears to be the caliper piston. But--all four brakes have a bad caliper piston??? I tend to think it must be a single-source problem, just not sure what that source of the problem is.

Both problems are nuisances, but do not affect brake performance. The disc brakes are strong and brake performance is checked prior to departure each tow day. Last item on the pre-departure checklist.

• Note to Country Campers -- the controller level was lowered to 6.5 from 7.5 as you suggested quite awhile ago.

Conclusion? There was still plenty of pad left, but I went ahead and replaced them anyway. (Peace of mind.) A set of pads is $20, so $40 to do all four brakes. I can live with that.

Finally, there was some concern about the "witness marks" on the disc, but I think they were caused by the (very) short movement of the trailer to center it in the driveway. The trailer has sat since 17 Oct (it was moved on 28 Nov).



If there's anything of substance found tomorrow I'll add it in another post.

There's a PDF attached that I made for myself. Posting it in case there's something useful in it for someone else. (I tend to forget stuff when the time between services is so long, so this document is in lieu of good brain cells. )


Bearing and Brake Notes to Myself 29 Nov 23.pdf

[Country Campers]

howson

Howard,

I know you said that the guides are free moving, did you check this with the whole assembly assembled? When reinstalling make sure the piston is pushed back and try to slide the caliper on the pins. The wear on the outer pad consistently points to stuck guide pins.

Also you mentioned changing the gain down to 6.5, not reading back thru the thread did this change pad wear? I would think that 6.5 may be pretty high for disc brakes, my drums are only at 5.5.


Brian

[howson]

howson

Howard,

I know you said that the guides are free moving, did you check this with the whole assembly assembled? When reinstalling make sure the piston is pushed back and try to slide the caliper on the pins. The wear on the outer pad consistently points to stuck guide pins.

Also you mentioned changing the gain down to 6.5, not reading back thru the thread did this change pad wear? I would think that 6.5 may be pretty high for disc brakes, my drums are only at 5.5.


Brian

I'll try moving the assembly tomorrow, Brian, and will report the findings. Not sure, though, what could be done if it doesn't move.

No idea about the wear vs gain setting. Overall the pad wear looks consistent--as mentioned easily could have extended the time on the trailer, but since I've got it apart so infrequently I threw on new ones.

[Jlawles2]

Howard to the end of your write up I'm going to add the adjusting of the grease gun tip: https://www.youtube.com/watch?v=Sq9MNUHwUFY

Also note that on the opposite side from the filler on grease guns is typically a plug or a check valve that will allow you to release the air trapped in the head that takes about 100 million pumps to push through the hose.

As for knowing which way the grease seals go on, USUALLY the rolled pate forming the main body of the seal goes OUT. The other thing is the inside will be where the opening in the seal is that lets grease or oil get to the spring that creates the seal around the shaft. I also noted that packing the groove on the inside of the seal with grease helps ensure the seal gets properly lubricated immediately during initial drive not having to wait on heat and centrifugal forces to get the lubrication to the sealing area preventing damage to the lips.

As for pad wear not being even, typically the outside pad is the one that wears the most. This is caused by a couple of factors (in my opinion): 1 - the piston pushes against a sliding pad in the caliper, this causes the outside pad to be PULLED into the rotor, thus when released the piston retracts allowing the inboard pad to freely slide away from the rotor leaving the outboard pad to wear slightly until either wear or something pushes the pad away from the rotor; 2 - the outboard friction surface of the rotor tends to oxidize faster than the inboard surface leading to increased roughness and wear on the outboard pad.

I suggest you have the rotors skimmed every time you change the pads as this will ensure you have a true parallel set of friction surfaces. Be prepared to immediately take the unit out for a test tow and burnish the new pads and friction surfaces before oxidation can set in. Burnishing helps create oxidation resistance as friction material gets embedded into the friction surface minimizing oxidation.

Note these are my observations and opinions. These are things I have learned and observed over the years. If you can find a 2 piece seal ditch the lip seal (you will like these much better due to the pure nature of how they work)

[Cate&Rob]

WRT gain setting, I purposely run my trailer disc brake towards the high end at 7.5. I like to feel the trailer pulling back during braking. Too many iterations of greased brakes, non-functioning brakes, etc . (Brake pads are not expensive.)

Rob

[howson]

I suggest you have the rotors skimmed every time you change the pads as this will ensure you have a true parallel set of friction surfaces. Be prepared to immediately take the unit out for a test tow and burnish the new pads and friction surfaces before oxidation can set in. Burnishing helps create oxidation resistance as friction material gets embedded into the friction surface minimizing oxidation.

How is this done?

[Jlawles2]

How is what done?

Skimming the rotors? Take the rotors to a local auto parts store and have them lightly turned. Unless the rotors have excessive run out, they should be able to just touch off and make a single pass of a few thousandths. This ensures that any radial ridges and wear patterns from the previous pads are removed thus increasing performance.

When you call the parts house ask if they can turn rotors from say a 85 RWD Caprice (GM was still using cast rotors very similar to your trailer rotors). Note in the picture below the similarity where the outer dust cap fits. The race boss is just below that and on the inboard side the same race boss and lip seal boss. And yes that is a picture from Rock Auto for a 1985 Chevrolet Caprice with the 5.7L gas engine.

[Scott'n'Wendy]

How is what done?

Skimming the rotors? Take the rotors to a local auto parts store and have them lightly turned.

Parts stores having that equipment is not nearly as common as it once was.... rotors have become toss away parts....you might have to make a few calls to find a place. At least you would up here in Canada.

[Cate&Rob]

I agree with both Jlawles2 Joseph and Scott'n'Wendy Scott . . . Lightly turning the rotors would be the ideal thing to do, but finding a place with both a machine and a competent person to run it will be far more difficult than it used to be. Most brake rotors are now separate parts from the hub and are usually replaced rather than resurfaced.

If the wear pattern on the disc is concentric and relatively smooth (even with small grooves) on both sides . . . I would not risk an incompetent shop screwing up my rotors.

Rob

[COReflection]

Parts stores having that equipment is not nearly as common as it once was.... rotors have become toss away parts....you might have to make a few calls to find a place. At least you would up here in Canada.

Being a GM tech for many years in a former life---and having turned hundreds of rotors and drums---there's no way I would want an auto parts store salesman doing that work for me at least the ones that now work in the stores here in CO. Maybe Napa---but that would be it! I would find a reputable auto repair shop and have them do the work or just replace them as others have noted. Rotors are much cheaper than they used to be.

[Wileykid]

WRT gain setting, I purposely run my trailer disc brake towards the high end at 7.5. I like to feel the trailer pulling back during braking. Too many iterations of greased brakes, non-functioning brakes, etc . (Brake pads are not expensive.)

Rob

I had the brakes turned up to that on my trailer, and found that although I liked the feel of the trailer pulling a little, the tires, depending on the road surface would sometimes unnecessarily lock up, I backed mine down to 6.5. The trailer is still stopping great.

[TucsonJim]

I had the brakes turned up to that on my trailer, and found that although I liked the feel of the trailer pulling a little, the tires, depending on the road surface would sometimes unnecessarily lock up, I backed mine down to 6.5. The trailer is still stopping great.

This is what I do also. Every time I pull, I drive at 20 mph and fully apply the brake lever in the truck. If any tires skid, I back it down. If there is a lag in braking, I increase it.

Jim

[Jims94vmx]

Thanks for this post. Going to tackle this soon. Are your axles and hubs 6k by chance. I did the disc brakes with a friend and can not find paperwork. Been reaching out to Eastern Marine where I originally got the Kodiak 12" disc brake assembly. Part 1561005 (think that is the number)

They just gave me a 2.25" ID grease seal number for Dexter. 010 036 00

[Yoda]

Adding to my own thread as I'm now 1/2 way through doing the bearings (and brakes) again. For new readers that may be seeing this for the first time, my '19 315RLTS suspension is a MORRyde IS and it has Kodiak disc brakes.

FYI, the last service was 22 Feb 22 (27,661 tow miles on trailer at that time). Today is 29 Nov 24 and total mileage is 41732 (so 14,071 miles since last service).

The street side inspection and service is complete. Bearings and races look and feel perfect--no issues.

Gee whiz info:

• The MasterPro 412920 seal (O'Reilly Auto Parts) is a relabeled Timken 412920 (referenced in post 29). See https://cad.timken.com/item/seals/oil-seals-inch/412920
• A cross-reference of part numbers to the original Dexter 010-036-00 is here: https://www.trailerparts4u.com/files...hart_11-11.pdf
• The installation direction of the MasterPro is not obvious (to me). On one side there’s a slight raised rubber lip. This side goes on the AXLE side. The other side of the seal the rubber is slightly indented. That side goes against the bearing.
  • Direction of installation verified with Timken customer support.

I thought I would a a note to the gee wise. Timken seals are made by National Seal Here is the complete catalog and some information for thought. https://www.timken.com/wp-content/up...talog_7707.pdf

Excellent write up Howard. To the readers - WARNING: Cross referencing can cause brain damage. I have found it is helpful to print out the information as you go so you have a written record, and file it in the trailer somewhere. This goes for all wear parts such as brakes and suspension parts. That way if you on the road and need something you know what to ask for at the parts store or when you order on line later.

I can attest to the same effort Howard whent through when trying to find what Set of Timken bearings and seals to get for my new axles. Unfortunate I did not keep a printed record of my search, and only have the bearing sets in the box. But I can back reference from there if I need to. I got the base information (bearing and seal numbers) off of my new axle build sheet - which you should also have a copy of in the trailer.

Hope this additional information helps.
Keith

[howson]

Thanks for this post. Going to tackle this soon. Are your axles and hubs 6k by chance. I did the disc brakes with a friend and can not find paperwork. Been reaching out to Eastern Marine where I originally got the Kodiak 12" disc brake assembly. Part 1561005 (think that is the number)

They just gave me a 2.25" ID grease seal number for Dexter. 010 036 00

That Dexter 010-036-00 seal is what came out of my hub.



The MasterPro / National / Timken 412920 is a suitable sub.

My trailer has the 7K IS "axles". To my knowledge the IS comes in 7K and 8K versions only. https://www.morryde.com/wp-content/u...-Guide_v18.pdf

I'm not 100% sure on the size of the Kodiak disc brakes on my unit, so can't help with that information.

Howard