Factory power brakes?

[ThreeQuarter]

I'm looking at a lot of original/survivor/restored pickups on the board and I'm seeing some nicely-equipped pickups that do not have power brakes. Power steering seems to be more common than power brakes.

My '68 C10 Custom was well-equipped from the factory and was kept mostly original. As it sits today it has power brakes, but I don't see that listed as an option on the glove box sticker. Did power brakes come as part of different RPO in this list? Or should I assume it was added later?

[Steeveedee]

My truck's SPID also does not indicate power brakes, and it has been in the family since '73. If I had to guess, I'd say the the Camper equipment included it, though I see that yours is not camper-equipped. I'm betting that someone will come along with an explanation. I have driven many vehicles with manual brakes and am fine with them. It's easier stopping with the boost, right up until the engine quits. Then, you have maybe three pumps before you have to stand on the pedal to stop. My wife may be able to get both feet on the pedal, but she wouldn't be strong enough even then, in a panic stop. My clodhoppers would get the job done, so it's good that she lets me drive the truck when pulling the travel trailer.

[FirstOwner69]

Power brakes were optional on all trim level trucks (edit: until 1971, more info below in post 6) and would have been listed on the SPID. My 69 3/4 ton did not have power brakes or gauges. It's a top trim CST and even came with bucket seats. When I bought the truck new, adding power brakes was part of the deal. Below is the SPID showing where I wrote "power brakes" and a copy of a portion of the purchase agreement that specifies "dealer install power brakes".

[Blazerowner]

My 72 blazer is pretty loaded and it doesn’t have power brakes on the spid. It has front disc and I don’t think manual brakes were available with disc.

[dtkarst]

I’ve had a few factory power brake and power steering trucks and only have the spids calling out power steering but not brakes. Doesn’t seem too uncommon to me. Here’s two for example. Ones an all original 71 Cheyenne with power steering, brakes and ac and the other is a 71 k10 with power steering and brakes but only lists the steering as well. Both pickups are very original and the k10 I’m the third owner and second on the title

[jocko]

For 67-72 1/2 ton and 67-70 3/4 ton - manual brakes were standard - power brakes would be denoted on the SPID with J70 RPO.

Power brakes became standard on 71 and newer 3/4 tons (edit: and ALL 4x4s, even half tons), so they should be present on the truck but not listed on the SPID.

All standard power brakes were dual diaphragm type except K10, it's was single diaphragm (and I assume C10s were single diaphragm also, if ordered)

dtkarst, I can't explain the orange truck's SPID - if it came with factory power brakes when new, it should have J70 on the SPID. Maybe it was a plant thing, or maybe a big block thing(?), but I couldn't find anything to back those theories up...

ThreeQuarter, yours should have J70 on the SPID if equipped with them new - so I'd have to assume they were added at some point, but who knows.

Blazerowner, yours should not have J70 on the SPID because it's a K.

Looks like there are certainly examples of exceptions to the rule for this though - I need to look a little deeper into this!

[FirstOwner69]

Originally Posted by jocko

For 67-72 1/2 ton and 67-70 3/4 ton - manual brakes were standard - power brakes would be denoted on the SPID with J70 RPO.

Power brakes became standard on 71 and newer 3/4 tons (edit: and ALL 4x4s, even half tons), so they should be present on the truck but not listed on the SPID.

All standard power brakes were dual diaphragm type except K10, it's was single diaphragm (and I assume C10s were single diaphragm also, if ordered)

dtkarst, I can't explain the orange truck's SPID - if it came with factory power brakes when new, it should have J70 on the SPID. Maybe it was a plant thing, or maybe a big block thing(?), but I couldn't find anything to back those theories up...

ThreeQuarter, yours should have J70 on the SPID if equipped with them new - so I'd have to assume they were added at some point, but who knows.

Blazerowner, yours should not have J70 on the SPID because it's a K.

Looks like there are certainly examples of exceptions to the rule for this though - I need to look a little deeper into this!

As usual, you are correct!! After I posted above, I started thinking that things may have changed when the trucks went disc in 1971.

So, I did some research using the GM Heritage Center info kits. The info there verifies, as you stated, that starting in 1971 the only trucks where power brakes were optional were the C-10s. All C-20s and C-30s as well as all K series had power brakes as standard equipment. AND, the 1972 kit also verifies that the K-10s used a single diaphragm booster and the K-20/30s used dual diaphragm boosters.

[Chris_oz]

My 1970 C20 Lomghorn SPID.

Lists Brake Booster Equip J70

[ThreeQuarter]

Thanks for the info. I’m going to consider this one a dealer (or later) upgrade.

Here’s a pic of mine when it was together. Seems to have a longer offset from the firewall than others I’ve seen on the board, and the MC points down. Also, does it look like my lines are bent forward, as if the MC was formerly located a little farther back?