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Old 05-26-2003, 01:31 PM   #1
miket
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Brake booster replacement

How do you ID the Brake booster to buy the right replacement part?
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Old 05-26-2003, 11:13 PM   #2
trukman1
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Brake Booster

Don't know if this will help but I only know of two boosters...The first is the single diaphram type that is of a larger diameter and thinner from front to back and the second is the dual diaphram version that is thicker and, if memory serves me right, is a smaller diameter. I swapped a unit from a '72 'Burb into my '67 and it turned out to be the dual diaphram type. It also uses a short throw plunger which only protruded about a quarter inch into the master cylinder vs. a longer (1" or more) plunger for the single diaphram booster. I used a stock corvette master with the shallow piston whereas the single diaphram unit used a plunger that extended out far more by at least an inch or more. I know this still doesn't give you much to go on but it's all I know to tell you right now. Hope this helps. Trukman1
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Old 05-27-2003, 08:22 AM   #3
JimKshortstep4x4
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Here is some information that may help you.

http://www.brakeboosters.com/booster.htm

In the picture, the top left is a Bendix and the bottom right is a
Delco booster. Out of the 9 trucks that we have with power brakes, (8) are Bendix and (1) is Delco.

Jim
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Old 05-27-2003, 09:22 AM   #4
No3Fan4Ever
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Which one is the most likely to be on a 3/4 ton truck?
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Old 05-27-2003, 10:15 AM   #5
JimKshortstep4x4
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I don't remember which one might be for a 3/4 ton truck. They were usually the double diaphragm type. I have one that I can look at later today and post a pic if no one else does in the meantime.

Jim
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Old 05-27-2003, 08:20 PM   #6
JimKshortstep4x4
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Here is a pic of a 3/4 ton Delco brake booster, front view.

Jim
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Old 05-27-2003, 08:25 PM   #7
JimKshortstep4x4
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Here is a pic of the 3/4 ton booster side view. As can be noted it is thicker than a single diaphragm booster as it has two diaphragms in it. (The double diaphragm is approx. 6" thick and the single is approx 4" thick).

Jim
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Old 05-27-2003, 10:14 PM   #8
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I didn't recognize it without any rust!:p
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Old 05-27-2003, 11:43 PM   #9
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I sold my repair manual, so i can't referance it nor name the manufacturers, but I believe there were actually 2 brands of daul diafram boosters that were quite differant
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Old 05-28-2003, 08:34 AM   #10
JimKshortstep4x4
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Andy,

I think that you are right on this. I took a dual diaphragm off of a 69 3/4 ton that was smaller in diameter and we used it on my son-in-laws 56 Chevrolet. The problem is there are no names or numbers on the diaphragms.

Jim
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