Carb to brake booster hard vacuum line, why can’t I find it!?!?

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PatinaTurner

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C
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Apologies if this has been asked before but I couldn’t seem to find an answer after a bunch of searching.

in my 81 Cheyenne, there’s a hard line running from the vacuum source in the carb to the power brake booster. Mine is absolutely crushed and obviously not working any longer but I simply cannot find a direct replacement at the usual places. Plenty of rubber lines, but nothing exactly the same at the parts stores or Rock Auto. I did find one site that I’ve never dealt with that did have them I’d feel a lot more comfortable getting it from a reputable and known site.

am I searching for the wrong thing or is it a needle in a haystack? Or should I just be replacing it with a rubber line?

thanks in advance.
 

nvrenuf

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If you're is a metal line then your "easiest" option will be to get some universal 3/8" steel tubing from a parts store and bend it to match the original. You might try Inline Tube as they make prebent brake and fuel tubing but I doubt there's enough demand for the booster tube to make it worth reproducing.

I've always just run rubber fuel hose without issue, there's not enough vacuum to collapse healthy hose.
 

PrairieDrifter

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squaredeal91

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I've only seen a couple of the hard line ones. It's usually all rubber. But I suppose a guy could make one from some brake tubing. I use it for different projects like this sometimes.

Oops. I didn't read enough. Just noticed
nvrenuf said it first lol
 

Rusty Nail

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There's no good reason to mandate a hard line there, rubber will be fine in 99.99% of all applications 35-45 years after the new truck warranty has expired.
Make it easy for yourself and move on to the next thing.
 

75gmck25

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The original hard line on my truck was shaped so it curved over and was supported by a grommet in the bracket for the throttle and the TH350 kickdown. Then there was a fairly short rubber line from there over to the brake booster. Very stable, but a PIA when you pulled the Quadrajet off. I don’t have mine running through the bracket anymore.

You don’t need to have the the hard line for proper function, but it moves that booster hose connection out into an area where it’s easier to get a pliers on the spring clamp when you disconnect.
 

Jeff Lewis

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rubber, attach it to any vacuum line with a T
 

KnuckleBuster

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Apologies if this has been asked before but I couldn’t seem to find an answer after a bunch of searching.

in my 81 Cheyenne, there’s a hard line running from the vacuum source in the carb to the power brake booster. Mine is absolutely crushed and obviously not working any longer but I simply cannot find a direct replacement at the usual places. Plenty of rubber lines, but nothing exactly the same at the parts stores or Rock Auto. I did find one site that I’ve never dealt with that did have them I’d feel a lot more comfortable getting it from a reputable and known site.

am I searching for the wrong thing or is it a needle in a haystack? Or should I just be replacing it with a rubber line?

thanks in advance.

First off, I like to keep things original, so I would use a metal pipe like the one it came with. You won't likely find one at a parts house. Best bet for an original is an antique junkyard. There are plenty of places online that sell used parts, as well as restoration parts. You didn't give the vehicle specifics, but it looks like LMC Truck has what you need for just under $20.

You can use a rubber hose. Lots of people do. But if the factory thought that was the best option they could have saved a fortune by using rubber instead of a steel pipe on millions of vehicles. The reason they did that was because steel pipes don't collapse under vacuum, which could cause a loss of power assist to the brakes. Aged rubber does collapse. Aged steel does not.

Good luck!
 

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