Author Topic: Which Brake System?  (Read 31633 times)

Offline 81Cheyenne

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Which Brake System?
« on: June 30, 2009, 08:24:11 am »
I'm rebuilding a 1982 K-24 Camper special.  How do I tell which brake system I have (JB5,JD7,JD6..etc)?
I'm wanting to get rid of the Hydroboost and convert to a Vacuum booster and I need to know which parts to buy. And no, I don't have the code sticker in the glove box. (rats)
thanks.

Offline frogman68

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Re: Which Brake System?
« Reply #1 on: June 30, 2009, 08:28:21 am »
If its Hydroboost wouldnt it be Jb8?

Offline 81Cheyenne

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Re: Which Brake System?
« Reply #2 on: June 30, 2009, 08:36:23 am »
If its Hydroboost wouldnt it be Jb8?
Dunno.  I guess that I need to know which system to buy parts for if I want to change over to a heavy duty vacuum type brake booster.

Offline 81Cheyenne

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Re: Which Brake System?
« Reply #3 on: June 30, 2009, 03:24:37 pm »
So, anybody have an opinion on changing a hydroboost to a vacuum boost?

Offline VileZambonie

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Re: Which Brake System?
« Reply #4 on: June 30, 2009, 03:37:18 pm »
Just go with the heavy duty brake system.
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Offline Captkaos

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Re: Which Brake System?
« Reply #5 on: June 30, 2009, 05:02:45 pm »
JB8 is the 1T brakes, I believe you would have JB7 on a camper special.

JB1 BRAKE, MANUAL, DISC/DRUM, 4300 LBS
JB3 BRAKE, POWER, DISC/DRUM, 4600 LBS
JB5 BRAKE, POWER, DISC/DRUM, 6400 LBS
JB6 BRAKE, POWER, DISC, DRUM 7200 LBS
JB7 BRAKE, POWER, DISC, DRUM 8400 L85
JB8 8RAKE, POWER, DISC, DRUM 10000 LBS

Personally I would keep the hydroboost.

Offline 81Cheyenne

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Re: Which Brake System?
« Reply #6 on: July 01, 2009, 06:59:55 am »
Personally I would keep the hydroboost.
Is hydroboost that much better than vacuum?  I'm going to have to replace the master cylinder anyway and was wanting to get rid of some of the lines. I'll also have to buy another power steering pump if I keep the hydroboost.

Offline Captkaos

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Re: Which Brake System?
« Reply #7 on: July 01, 2009, 04:01:12 pm »
Better is a vague term.  I just wouldn't remove it just to have Vacuum.
AND on a 3/4T truck you would need the HD booster if you changed it.

Offline BigHemi353

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Re: Which Brake System?
« Reply #8 on: July 12, 2009, 12:24:13 am »

JB1 BRAKE, MANUAL, DISC/DRUM, 4300 LBS
JB3 BRAKE, POWER, DISC/DRUM, 4600 LBS
JB5 BRAKE, POWER, DISC/DRUM, 6400 LBS
JB6 BRAKE, POWER, DISC, DRUM 7200 LBS
JB7 BRAKE, POWER, DISC, DRUM 8400 L85
JB8 8RAKE, POWER, DISC, DRUM 10000 LBS

I have an 86 3/4 4x4. the code for my power brakes in the glove box are 1J55. Would this be JB5? My truck has the 6001-7000gvw brake system.
-1986 Silverado K-20 6bt Cummins / NV4500/ np205- under construction

Offline 78 Chevyrado

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Re: Which Brake System?
« Reply #9 on: July 12, 2009, 02:35:04 pm »
I looked on my build sheet for my '78 C20.  It has the H.D. Vacuum Powered Brakes

It's listed like this on the build sheet:

  J55  H.D. Power Brakes
=JB7  Vac Power Brakes


On the RPO sticker:
 J55  H.D. Power Brakes



Kenny

1978 C-20, 350/400, 3.73, Graystone Metallic, Raceline Renegade 8 Wheels - 18x8.5, 275/70R18 BFG KO's

Offline BigHemi353

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Re: Which Brake System?
« Reply #10 on: July 12, 2009, 02:41:16 pm »
Thanks Chevyrado! You've saved me alot of hair pulling at Autozone! lol
-1986 Silverado K-20 6bt Cummins / NV4500/ np205- under construction