gmt400 K1500 rear disc conversion w/ master cylinder upgrade

I know I'm beating a dead horse here but I'm at my wits end of a week of constant researching and forum reading and I know there are some real experts here, and I'm definitely not an expert.

I just bought a 99 K1500 suburban JB6 brake package. I've had my share of GMT400's but this one needs a brake overhaul. I don't need it to stop on a dime, just need it better than what it is now.

My plan is to do a rear disc upgrade from Little Shop MFG (www.littleshopmfg.com) AND swap to a GMT800 MC and braided hoses on front and rear. I was planning to keep the JB6 booster and front calipers and rotors.

My question(s) is:
1 - any issue with this setup? Too much pressure to the rears instead of majority going to the front? Is a proportion valve needed?

"I was told" the ABS unit does the proportioning (assuming ABS does not get air in it) and since the GMT800 MC is for disc / disc this seems logical except that the GMT800 might have larger front rotors requiring more pressure?

2- Is there any difference in a JB6 vs JB7 booster? Does it make sense to put a new JB6 or JB7 booster in since I'll have it all ripped apart?

Any help is greatly appreciated.

Cheers,
Chuck

I bought the same setup you are talking about and am thrilled with the performance. Only issue I have run into is getting a parking brake cable the proper length to work with the parking brake version I got from littleshopmfg. It seems like I am going to have to get creative. I have the gmt800 master and stainless cables front and rear and everything works great.


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What issues are you having?

97Tahoe4wd said:

I bought the same setup you are talking about and am thrilled with the performance. Only issue I have run into is getting a parking brake cable the proper length to work with the parking brake version I got from littleshopmfg. It seems like I am going to have to get creative. I have the gmt800 master and stainless cables front and rear and everything works great.


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Awesome! Thanks for the feedback!

Is the parking brake cable too short? How long ago did you do this ?

shamrock246 said:

What issues are you having?

Click to expand...

I think he's saying his parking brake cable is too short?

The issue I am having is that the sleeve of the parking break cable is about 7 inches too short. The internal cable length will work, but the sleeve is too short. It’s too short because the bracket relocated the connection about 6-7 inches back from where it would connect to the back in plate of the drum brakes.


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97Tahoe4wd said:

The issue I am having is that the sleeve of the parking break cable is about 7 inches too short. The internal cable length will work, but the sleeve is too short. It’s too short because the bracket relocated the connection about 6-7 inches back from where it would connect to the back in plate of the drum brakes.


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Does the parking brake still work?

Nope. The brakes work, but not the parking brake.


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97Tahoe4wd said:

Nope. The brakes work, but not the parking brake.


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Has Little Machine offered any solutions?

I haven’t mentioned it to them yet, been busy with other stuff currently.


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