When To Replace Your Brake And Hub/Drum Assemblies And How To Handle Discoloration On The Spindle

Published 03/20/2024

Question:

What does UC3 mean? I bought 2 drums before 2020 and there was not UC3 at the end of the numbers. Are those genuine Dexter parts?. I have a little over 1/16 left on one pad I would think, can you look at the photo and give me your opinion? If I change the back plate, is it best I change the drums too? have them turned? Also the Dexter manual mentions to check for discolouration on the spindle, I have some collars on the spindle, could you check the photos if that is ok? Thank you very, Julie

asked by: Julie P

Spindle Discoloration
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Brake pad thickness
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brake assembly
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Expert Reply:

Hi Julie,

UC3 is added on to this part number because we offer parts with the same part numbers from multiple manufacturers so a code or extra numbers get added on to differentiate the parts. If you scroll down on the # 8-388-80UC3 page you'll see the manufacturer's part number (pictured below) after the item description.

Dexter recommends replacing the brake assembly when the pads get down to 1/16" (.0625") in order to prevent damage to the hub or failure of the brake assembly. They recommend replacing the hub/drums every time you replace the brakes because they build a groove and form to each other over time. They follow very strict guidelines to make sure that everything is perfect each time. Most people however, just check the drum for any deep scratches or gouges and replace as necessary. If you can get them turned for a reasonable cost then that's the route I'd take.

When it comes to light duty (axles under 8k) brake assemblies it's typically cheaper and easier to just replace the entire assembly rather than replacing the shoes. Replacing the assembly will also give you a new warranty in the event that anything malfunctioned. If you do want to replace the shoes you still can but you'll likely have a hard time because the shoes are held in place with tight springs that don't want to cooperate.

The discoloration on the spindle is concerning because it's right where your grease seal sits. If the grease seal fails it will allow water, dirt, debris, etc. into the hub and can bind up or corrode the bearings. If your bearings bind up the wheel won't want to spin and it'll heat up and destroy the spindle. You can try lightly sanding the rust with some very fine sandpaper to remove some if it but you don't want to sand too much and build a groove in the spindle. You're likely looking at needing a new axle in the near future, but could probably ride this one out just a bit longer.

When you do end up having to replace the axle you'll need to know the capacity, hub face to hub face measurement, and spring seat to seat seat measurement.

expert reply by: Kevin C

8-388-80UC3 Part Number
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Axle Measurements
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Julie P.

3/20/2024

Thank You for your Prompt response, I have Nev-R-Lube bearings, maybe it is more protected from debris. I noticed those marks on the spindle 4 yrs ago, I did not know then it could be an issue. Nothing seems to have gotten worse but I will litly sand and keep a close eye on the spindles and a possible Axle replacement.