Need Help Advice On Rear Disc Conversion On DRW DUALLY

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GoToGuy

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Your "Friend " obviously didn't want anything to do with it. Did you actually look at any later duallys , take a look at caliper mounts? Take tape measure and measure the spring mounts? A lot of negative whining about regear rebuild with no facts. And you started off with how much $$$$ the project would be to start.
Do you live in rust belt? If so how often do wash/ rinse off underbody frame running gear?
Want wheel cylinders to last longer? Do a yearly, once a year , buy a new can of brake fluid open bleeder farthest from master, with bleed hose in clean bottle, three full brake pumps. Flush old out with new. Repeat with all others. Guaranteed to increase the life and reliability of drum brake wheel cylinders. Adjust shoes if necessary. You bleeder fittings to last, when you open to bleed coat threads you see with anti seize before closing bleeder.
Are those calipers actually rated for the weight a dually is capable of carrying?
 

1998_K1500_Sub

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GM's GenII F-body (70-81 Camaro/Firebird) had a rear disc brake option from IIRC '79-'81.

Here are pictures of GM's OE caliper mounting plates. These are akin to the plates sold by Little Shop's (and others) with one notable exception - GM's have abutments that fit against the center of the caliper, and they transfer the braking forces into the rear axle.

When you see those flat spots cast/machined into the OE caliper on each end (see picture), that's their purpose... the caliper's designed to press against abutments like these during braking.

Compare GM's OE design in the pictures below to the picture in post #17 in this thread or the video in post #21, and notice how the "kit" brakes do not support the OE caliper as it was designed to be supported.


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ForeverFalcon40

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I guess that would depend on which rims you have.

That video is somthin' else. Talk abut screw-ups!
I'm Running 19.5 Steelies in factory lug pattern. I have been looking for 19.5's in Semi Lug Pattern...they are RARE. This is the biggest I want to go b/c I want to lower my truck. I actually use it for work, lowering it would make it more functional for me.

What Video?

Sorry for the delay I ended back up in the hospital unexpectedly.
 

ForeverFalcon40

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x2.

Really easy to end up with worse braking ability than the truck had to begin with--if everything was working as intended.
Great Question!

As of right now I don't notice any braking issues. Most I had loaded in the bed was about 1k worth of weight. I don't speed at all...keep it in the 55-60MPH with the CC on in the middle lane. I did have one quick yellow light which forced me to slam on the brakes and the truck stopped. That was empty not loaded. The most this truck will ever haul is 5-6 yards of mulch 2x a year and a cummins 12v when the time comes.
 

ForeverFalcon40

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Your "Friend " obviously didn't want anything to do with it. Did you actually look at any later duallys , take a look at caliper mounts? Take tape measure and measure the spring mounts? A lot of negative whining about regear rebuild with no facts. And you started off with how much $$$$ the project would be to start.
Do you live in rust belt? If so how often do wash/ rinse off underbody frame running gear?
Want wheel cylinders to last longer? Do a yearly, once a year , buy a new can of brake fluid open bleeder farthest from master, with bleed hose in clean bottle, three full brake pumps. Flush old out with new. Repeat with all others. Guaranteed to increase the life and reliability of drum brake wheel cylinders. Adjust shoes if necessary. You bleeder fittings to last, when you open to bleed coat threads you see with anti seize before closing bleeder.
Are those calipers actually rated for the weight a dually is capable of carrying?

He is really good to me as I am back to him. I never considered a later dually. I only considered the HD model I found at the junkyard. Running the HD model would have given me a smaller wheel base which have been better so my tires fit/tuck under the flares.

I'm not rich nor poor, when it comes to this truck. Money isn't an object within reason, he really wanted me to focus on 12V vs something like this at the time as just got done doing an extensive amount of work to it (maintenance and upgrades).

I do live in the rust belt. After doing snow removal within 48 hours I pull the outter rear tires and take it to a car wash.

I think my issue was bleeders rusting from the inside. New Calipers installed, I coated the bleeder threads with antiseize as usual. I went on amazon and ordered grease fitting caps. I installed the grease fitting caps. Before I closed the cap I put a dab of grease on opening of the bleeder.
 

ForeverFalcon40

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GM's GenII F-body (70-81 Camaro/Firebird) had a rear disc brake option from IIRC '79-'81.

Here are pictures of GM's OE caliper mounting plates. These are akin to the plates sold by Little Shop's (and others) with one notable exception - GM's have abutments that fit against the center of the caliper, and they transfer the braking forces into the rear axle.

When you see those flat spots cast/machined into the OE caliper on each end (see picture), that's their purpose... the caliper's designed to press against abutments like these during braking.

Compare GM's OE design in the pictures below to the picture in post #17 in this thread or the video in post #21, and notice how the "kit" brakes do not support the OE caliper as it was designed to be supported.


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Gotcha Only Time Will Tell! I was driving the truck once a week as instructed by the kit to keep everything in adjustment. I was in the hospital again so it kinda disrupted a few things. I'm playing catch up. Been taking the truck on short trips as of right now bc thats where my travels take me. Also trying to remember what else was wrong with the truck before I went out of commission for a year.

I have to check my cluster but I'm sure I am over 100 miles maybe more. At that mark I wanted to pull the tires and check torque on things and re-install.

Is there anything you would like me to document while I am in there?
 

1998_K1500_Sub

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