The Stovebolt Site Forums The Parking Lot '60-'66 Trucks Brake drum irritation

So my son and I finished up doing the brakes and bearings on all four wheels today, got the final adjustments and everything done. I had a bit of a roadblock with the drums though...Two drums were too far gone to turn, so I bought new ones from NAPA.

The drums that were on the truck had the adjuster hole in the drum, not the backplate. Which was a whole other problem before, because the truck had been sitting for 10 years and the rear wheels were completely locked up, so I couldn't turn them to line the hole in the drum up with the adjuster to back off the brakes! But back to today...

The one I got at NAPA didn't have a hole in them. I called around, and every parts place that had drums for a '66 in stock confirmed that theirs didn't have the hole in them either. I even called LMC truck, theres is also hole-less. I ended up drilling and cutting a hole in the backplates so I could adjust the brakes, but it seemed odd to me that no one had ever heard of this before. Is my truck unique, or is this something you guys have seen in the past? My theory is that the part number that comes up at NAPA et all is a generic Chevy drum, used on many cars, most of which have the more common adjuster hole in the backing plate, and the pick ups just fell through the cracks. Weird thing is that this can't be the first time somebody has needed new drums for a 66 Chevy C10.....

... I'm not the 66 guru but could it be it has self adjusting and the hole was deleted??.... but heck, even on self adjusters I've seen have a hole in the back.
I'm watching to learn something myself!! (when was first year for self adjusters?)

1964 was the first year for self adjusting brakes on the Chevy's.

Erik, you may want to rebuild the self adjusters on your truck. You can buy a complete rebuild kit.

When I bought replacement drums from Autozone last year , none of them had the adjustment hole . I had to drill then file them by hand . It wasn't too bad to do , just took a little time !

They are self adjusting, but its still good to adjust them the first time when you do the brakes, and once they are worn it can be a PITA to get teh drum off if you can't back off the shoes....

I just did the brakes, coleaned and replaced as needed...The adjusters seemed to be in good shape, I re-used them...

Yeah, I wound up making adjuster holes myself. I put them in teh backing plate, it was actually easier than I thought, thats some pretty soft steel!

How does one know that the brakes actually need to be adjusted after you do a brake job? I've replaced my master cylinder, wheel cylinders and shoes. I have not taken it out on the road yet and am a little apprehensive about doing so w/o a brake adjustment.

If I do need to adjust them, how do I do that? I know where the adjuster is and how to access it.

as you turn the drum adjust the brakes until you hear them start rubbing. another harder method is adjust til you can't turn the drum and then back off until you can.

With drum brakes, I have always tightened them till I can't turn the wheel, then backed off till the pads are just rubbing the drum. My Dad taught me that, he said that tightening them all the way up gets the pads aligned with the drums...I have no idea if you actually have to do that or not. You should adjust them though, it will help to make sure all the wheels are stopping more or less evenly and keep the truck from pulling one way or the other under heavy braking.....

As always, great and easy instructions. Thanks guys!

I always hit the shoes(like I was clapping) to make sure they are seated and use a brake shoe cliper to adjust the shoes to the drum initally. I was also taught to adjust the shoes tight and then back them off 6 to 8 clicks. This is not an easy task with auto adjusters, usually use a small screwdriver with a bend in it to release the adjuster arm and hold it off the star wheel. The Dana rear in my GMC has the slots in the backing plate.