Driver's side drum getting hot after brake job

[Shran]

Weird problem - I did a brake job on my '94 and it included new shoes, drums, hardware. The driver's side drum is getting pretty hot and the passenger side one is not - I drove it a few miles and checked it with an IR temp gun - it gets up to about 170 degrees and the passenger side one is at about 90 degrees. It got hot enough to turn the OD of the new drum sort of a straw color.

I tried a different wheel cylinder and star wheel adjuster. Neither made a difference. The shoes are not super tight, I can slip the drum off fairly easily without loosening them.

Kind of at a loss here. Do I have a bad drum maybe? The old brakes were not hanging up at all, they worked fine, I swapped axles to get a different gear ratio and figured I'd do a brake job on it while I had it apart.

 

[fastpakr]

Bad bearing at the end of the axle?

 

[Uncle Gump]

Confirm both shoes are firmly seated on the anchor pin.

If not the park brake cable is too tight.

 

[Shran]

Bad bearing at the end of the axle?

Man I don't THINK so... there is a very tiny amount of lateral play in the shaft but I compared it to a couple other axles in the pile and it's not really any different than those.

I put a dial indicator on the shaft and let the truck run in gear with no drum - just to rule out a bent shaft - there was maybe like 0.005" of runout. Not much.

I guess I could replace the shaft & bearing, I have plenty of spares but let's leave that for a last resort.

Confirm both shoes are firmly seated on the anchor pin.

If not the park brake cable is too tight.

Shoes are seated as far as I remember...I've had it completely apart several times and didn't notice anything weird. I will double check.

Does the parking brake pull on the driver's side first? I didn't adjust it at all, nor have I engaged it... ever... figured since the drum slipped on & off fairly easily I wouldn't need to?

I'm gonna run the drum down to the parts store and see if they can put it on their lathe and rule out a bad drum. This was a $10 Rock Auto closeout item so it's possible it's out of spec.

If that checks out I may swap drums from side to side and see if the problem follows the part.

 

[Uncle Gump]

If you can wiggle the park brake strut... the cable isn't too tight. I also think the park brake pulls the passenger side first.

Perhaps a long shot... but the backing plate isn't grooved bad enough to not let the shoe return properly?

 

[Shran]

@Uncle Gump your expertise was very helpful... thank you.

I think I have it fixed - I changed 3 things:
#1, had the drum turned. The guy who turned it wasn't there when I picked it up but the other guy said they wouldn't have turned a new drum if there wasn't something wrong with it... so I'm guessing it was out of spec somehow.
#2, I did find a shallow groove in the backing plate where the shoe contacts it but only on one of the little pads. I smoothed that out with a flap wheel.
#3, I greased all of those wear pads and the anchor pin. Admittedly I have NEVER done this... never. Didn't feel it was necessary as I've never found any grease there when disassembling old brakes... but it can't hurt.

Took it out for a drive and that drum stayed much cooler. Figured I would take the other side apart & re-check/grease that and found a damn seal starting to leak!!! So now it's torn apart for new bearings & seals, which I should have done to begin with.

Normal looking:

This one had a visible groove worn in it.

 

[Uncle Gump]

Ya know... I was taught that way in school. It was reinforced by my mentor starting out as a mechanic. His reasoning was to prevent a squeak when braking... which would certainly be a comeback. But it's really two-fold.

If it's squeaking... metal to metal... and it's wearing that dreaded groove.

Another note...

The bigger the squeak... the further out you are on the brake adjustment. If it just a tiny squeak... brakes are probably adjusted fine... but dry and wearing grooves in your backing plates.

Your groove doesn't look that bad... but it might have been enough.

 

[Shran]

The other side had a groove that was worse but it wasn't dragging so I guess I'm at a loss as to what exactly caused it but am not complaining either.

I did notice that after greasing everything, the assembled shoes return to center by themselves if I push it off center. Prior to that they would not have returned to center at all without pushing them there... so I guess that by itself is a good thing. I will just consider myself educated & do better brake jobs from now on.