Identifying heavy duty vs not heavy duty brakes

[jcwren]

Last weekend I snapped up a 1970 C10 long-bed step side. It was a father-daughter restoration project that was mostly complete, but they need to sell. There is not a spec of rust on this truck, it's been repainted, new interior, lots of other new parts. It has the extra load springs, also. 250 CID, 3 on the three.

It's got an Offenhauser 3 carb intake, along with 3 TMC 1-123 carbs for it. To get it finished, I need to install the carbs, battery, inner wheel wells (came with those), front and rear bumpers (came with), bed (need to get a bed kit), and do the brakes. Which gets me to the point of the question...

Autozone and a few other places have wheel cylinders, but have both heavy duty and non-heavy duty cylinders. Is there something that identifies which the truck has? One of the front ones is leaking, and the brake hardware is a little rusty and gunky in that wheel, so I'm planning on new cylinders, shoes, and hardware for the front. The back brakes are dry, and the hardware is decent.

Any advise for a newly minted C10 owner?

Link to albumn w/ pictures

[rsavage]

Pull one off and take it with you to compare.

[Jrainman]

I dont remember off hand but heavy duty brake pads I think where wider then standard. I think 2 inch wide but could be wrong , also I would replace all the hardware when doing a brake job the hardware Kit is cheep and worth replacing

[PDXk5]

Standard drum brakes are 2 inch wide. The heavy duty brakes are 2 3/4 inch wide and can be found on 76 to 87 and 10 bolt rear end K series rigs.

It's a fairly simple swap to do if you have the standard drums and want to change to the later heavy duty version. I recently had my rear end refurbished and upgraded the brakes to the heavy duty version at that time.

[Ironangel]

Thats a clean old stepper! I'm "Ironangel" from the 67-72 GM Truck Board...I was wanting to get a peek at the rear axle and suspension. And maybe a front brake assembly with the drum removed? Also take pic of the "SPID" (Service Parts Identification Label) and it will note the heavy duty options added. Leaf Springs are an option, fleet vehicles, state and government vehicles were often HD optioned...Cool truck! Pull the drums and measure the brake shoe width

[rsavage]

Originally Posted by jcwren

Last weekend I snapped up a 1970 C10 long-bed step side. It was a father-daughter restoration project that was mostly complete, but they need to sell. There is not a spec of rust on this truck, it's been repainted, new interior, lots of other new parts. It has the extra load springs, also. 250 CID, 3 on the three.

It's got an Offenhauser 3 carb intake, along with 3 TMC 1-123 carbs for it. To get it finished, I need to install the carbs, battery, inner wheel wells (came with those), front and rear bumpers (came with), bed (need to get a bed kit), and do the brakes. Which gets me to the point of the question...

Autozone and a few other places have wheel cylinders, but have both heavy duty and non-heavy duty cylinders. Is there something that identifies which the truck has? One of the front ones is leaking, and the brake hardware is a little rusty and gunky in that wheel, so I'm planning on new cylinders, shoes, and hardware for the front. The back brakes are dry, and the hardware is decent.

Any advise for a newly minted C10 owner?

Link to albumn w/ pictures

If you are unsure of which wheel cylinder you need, I, once again, suggest you take one with you so that you can compare. I also suggest you get new hoses, Take your shoes too. If the drums are bad, see if they can be turned. If it has been a while since you have done drum brakes, take some photos before you pull it apart so that you can see which way the spreader bar, springs and adjusters, emergency brake bar, etc. go each side. Clean the backer plates and where the shoes run and put a tiny bit of grease on the nubs. Make sure that the shoes are in the correct position - long and short. Good time to clean the front wheel bearings, check them out, and repack using new seals. You probably know all this. Good luck with your brake job.

[68Gold/white]

Originally Posted by PDXk5

Standard drum brakes are 2 inch wide. The heavy duty brakes are 2 3/4 inch wide and can be found on 76 to 87 and 10 bolt rear end K series rigs.

It's a fairly simple swap to do if you have the standard drums and want to change to the later heavy duty version. I recently had my rear end refurbished and upgraded the brakes to the heavy duty version at that time.

I sold auto parts for 13 years.....the answer(s) is/are....

The rear brakes on all the pickups till 73 (yes 73 is the first year square body) are all 2" wide, 11" I.D. drums... I believe this started in 1960, not remembering well, I didn't sell much 60-66 stuff.

There WAS a heavy duty option from 67-72 for the front drum brakes.

I never sold the HD shoes, EVER for a pickup,
BUT towards the end of my parts store days (1985-1998) a friend came in for front shoes for his Suburban. IT DID have the heavy duty brakes on it. I've never seen them before or since. I'm guessing the HD brakes were most likely only mostly on Suburbans...

Every time I looked up the front brakes for a 67-70 pickup and asked what size the shoes were, I wondered for a long time IF any pickups came with HD front brakes, seemed like I was wasting my breath asking about shoe size.

There;s folks here that swear that the front drum brakes are adequate for any stopping situation, I STRONGLY disagree. Front disc brakes are SO much better!!! You don't need to go crazy with disc on the back, the factory front disc setup is awesome!!!

The heavy duty rear shoes started in 1974, you could get either the 11X2 shoes. OR the 11-5/32 X 2-3/4 shoes on the rear, depended on how the pickup was ordered. The rear HD drums are also different,
You can change to HD rear drum brakes, BUT, BUT you must also change the backing plate, no other way to do it...