Flaky pastry Brake drums !

[Mellemel]

I recently had a rear wheel/brake cylinder replaced and have since had a vibration happening around 50mph that wasn't there previously. I have 376,000km and the drums are very rusted to the point that I can almost peel chunks of rust off with my fingers, tapping with a hammer breaks chunks off !

Am I overdue on replacing my drums ?? When I spin them by hand they don't rub, on the pads or anything, I'm thinking the rust is causing an imbalance. What kind of 4Rnr age or mileage did anyone replace their drums at ?

 

[I_bRAD]

I replaced mine recently at ~320000 kms. They were rusty, but were replaced because they were worn out.

Did the person who replaced the wheel cylinder say anything about the condition of the drums? This just started after you got your brakes done?

 

[Mellemel]

Yup, about a day after the work. They never commented on the drums condition at all. I went back and they balanced the rear wheels, which did make a slight improvement and reduce the vibes.

Inside the drums there is a groove worn where the pads make contact, is that normal for such a groove ? it maybe about an 1/8 inch worn down ! Can you remember what yours looked like ? How did you determine yours were worn out ?

I had a new U joint this year so I am ruling that out as a cause.

 

[Morphyne]

The groove is normal and alwith that many miles. Everything on you truck is a maintainance item. Replace your drums I am betting that the vibration will go away.

 

[Mellemel]

I think it's time for new drums. Certainly can't hurt.

 

[I_bRAD]

Yup, about a day after the work. They never commented on the drums condition at all. I went back and they balanced the rear wheels, which did make a slight improvement and reduce the vibes.

Inside the drums there is a groove worn where the pads make contact, is that normal for such a groove ? it maybe about an 1/8 inch worn down ! Can you remember what yours looked like ? How did you determine yours were worn out ?

I had a new U joint this year so I am ruling that out as a cause.

Mine were worn down the same, that's why I replaced them. They do have a max dia, but I don't have the equipment to measure it properly. For what it cost, and how often they need replacing I just went ahead and did it. I used toyota factory rotors which were slightly more than the "premium" aftermarket, but significantly more than the economy version- they were suspiciously cheap and for the time they last the factory was worth the extra IMO.

It's odd that it happened right when you had work done on it. I wonder if they managed to warp the drums trying to get them off.