HOW TO Convert From Drum Brakes to Disc Multi Part Video Series

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ForeverFalcon40

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Mandingo is a 1996 GMC K3500 CCLB DRW 6.5TD 80E 14B (say that 10x fast LOL)

Its Simple...

Drum Brakes Suck and everything has to be taken apart to repair/replace them.

There is a timestamp is you want to get to wrenching. Will Update Post as I release videos or just hit notifications button on youtube and you will be notified when I drop the next video. This video is NOT sponsored in anyway. If you don't have a dually but you want to convert to Disc PLEASE USE TSM MFG.

Their customer service in something I rarely experienced!


Here is the link to Part 1:
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454cid

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I don't understand why all these disc conversion companies don't start using more modern calipers instead of relying on these old tiny designs. It would also be nice if they'd design brackets that properly support the calipers. I've seen ONE company that does, but it was for a niche vehicle, and I can't recall what it was.... nothing that would fit out trucks.

If I ever convert to rear discs, I'll grab a GMT-800 14bff, or the 11.5" and move the spring/shock mounts.
 

ForeverFalcon40

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I don't understand why all these disc conversion companies don't start using more modern calipers instead of relying on these old tiny designs. It would also be nice if they'd design brackets that properly support the calipers. I've seen ONE company that does, but it was for a niche vehicle, and I can't recall what it was.... nothing that would fit out trucks.

If I ever convert to rear discs, I'll grab a GMT-800 14bff, or the 11.5" and move the spring/shock mounts.
In the video I discussed why swapping rears wasn't an option. If I did do the rear it would be from an OBS HD series truck again all covered in the video.

As far as "size" understand your concern but I have yet to notice or feel the need for "more" brakes. I just hauled about 1k load in the bed for about an hours worth of driving stop/go/highway and never felt more confident to hit the brakes. Only once I had to apply more force than normal when I was on the highway and someone merging on cut me off. Hit the brakes and layed on the hornblasters. Hornblasters scared them off the road and into a ditch. When this happened I was "empty"
 

offroadtahoe

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Great video,I did a rear disc too (14bff) what i liked most about it.The brake pedal engages instantly and is consistant,It doesn't start to get soft for like 1/2 an inch,and need adjusting

also here is a easier way for rusted brake lines. https://www.offroaddesign.com/catal...lines-for-disc-brake-conversion/category/402/

tip i wish i knew when doing mine,open a brake bleeder,push the brake pedal in and have it held in position with something,now you can work and the master cylinder will stay filled,so you will only have to bleed the line
 
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Schurkey

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I looked at the TSM web site. ANOTHER company selling junk flat-bracket conversions for use with calipers not designed for 'em. I feel like a broken record explaining why that's potentially unsafe.

Drum brakes don't suck when they're kept in proper working condition, and when they're sized appropriately for the vehicle and usage. Drum brakes were grossly undersized on passenger cars for decades. They were replaced in the late-'60s and '70s with somewhat less-undersized discs. When disc brakes were "new", guys pissed and moaned about how hard they were to work on, and how precise everything had to be. It's just a matter of what the guy working on them is used to.

I hope the discs you installed have AT LEAST as much stopping power as the big (13 x 2.5?) drums you removed. If the kit you bought uses passenger-car calipers on those 12.5" or 12.75" rotors, I have a suspicion that you have less braking now than you did before.
 
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ForeverFalcon40

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Great video,I did a rear disc too (14bff) what i liked most about it.The brake pedal engages instantly and is consistant,It doesn't start to get soft for like 1/2 an inch,and need adjusting

also here is a easier way for rusted brake lines. https://www.offroaddesign.com/catal...lines-for-disc-brake-conversion/category/402/

tip i wish i knew when doing mine,open a brake bleeder,push the brake pedal in and have it held in position with something,now you can work and the master cylinder will stay filled,so you will only have to bleed the line
THAT is awesome! The first upgrade I do on any "new" vehicle to me is SS Braided Lines...Its just cheap insurance/performance. TSM use to have lines included in their kit but they got a few complaints from customers that they weren't happy on how they were routed. They made/had made lines to their satisfaction and wanted to return the ones with the kit as well as get compensated for it. TSM is small Mom N Pop Machine shop with 3 workers (husband, wife, helper). I live in the rust belt, so I made my own lines using nickel copper which is very easy to work with which is perfect for someone like me who has limited experience. I LOVE SS Braided Lines...here is a underbelly photo of a one off system I built and installed. It took a lot longer than I want to share but now that I taught myself how to make my lines...want to SS BRAID the entire truck LOL. It has crossed my mind to every brake line on the truck from master back ; )
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ForeverFalcon40

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I looked at the TSM web site. ANOTHER company selling junk flat-bracket conversions for use with calipers not designed for 'em. I feel like a broken record explaining why that's potentially unsafe.

Drum brakes don't suck when they're kept in proper working condition, and when they're sized appropriately for the vehicle and usage. Drum brakes were grossly undersized on passenger cars for decades. They were replaced in the late-'60s and '70s with somewhat less-undersized discs. When disc brakes were "new", guys pissed and moaned about how hard they were to work on, and how precise everything had to be. It's just a matter of what the guy working on them is used to.

I hope the discs you installed have AT LEAST as much stopping power as the big (13 x 2.5?) drums you removed. If the kit you bought uses passenger-car calipers on those 12.5" or 12.75" rotors, I have a suspicion that you have less braking now than you did before.
Rotors are are massive and HEAVY! These kits have been installed on a few tow trucks with no issues unless installer error which he highlighted in the instructions with photos.

Keyword "Potential" I've put on close to 500 miles since the install. At roughly the 100 mile mark, I jacked up the rear pulled the tires and torque checked everything with no issues. I have about 1000 miles on the truck as no issues as of right now. I had a load of about 1k in bed and felt confident every time I hit the brakes. When I was empty, a driver cut my off while merging onto the highway. I hit the brakes and the hornblasters and sent the driver into the ditch. Considering the situation, I felt the brakes handled well. The issue with mine was keeping them in operating order. I coated everything in anti-seize as far as adjusters and bleeders still ran into issues whenever I needed to work on the system. Quite frankly I was fed up and I put a price on happiness. We discussed this on my OG thread, before I knew this kit existed a few years ago I wanted to grab a rear from an HD C3500 as they come with discs. This is a project that is out of my wheel house and I'm sure would take me a longer than most. A Good buddy of mine who is extremely mechanically inclined said its not worth it. I would have to purchase the rear, rebuild it, re-gear it, new driveshaft made, new lines and if none of the brackets line up...make them line up. I told him thats fine, a lot more work than I anticipated but I have a budget of $5-6k. I already located a rear at that time and I even took a photo of the VIN on the truck. The yard wanted $1,500 for the rear I already asked when I was there. I'm like...here is the VIN...order the parts and get this ball rolling. Basically was like...rather have you put the funds towards a 12V swap.
 
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Schurkey

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I LOVE SS Braided Lines...here is a underbelly photo of a one off system I built and installed. It took a lot longer than I want to share but now that I taught myself how to make my lines...want to SS BRAID the entire truck LOL. It has crossed my mind to every brake line on the truck from master back ; )
Making hydraulic hoses was my job at The Bus Plant for about a year. Best I can figure, I made about 20,000 hoses, more-or-less. Most of them fabric braid over steel-reinforced rubber, (Aeroquip FC300 and Aeroquip FC350) but plenty of single- (Aeroquip 2807) and double-steel-braid (Aeroquip 2808) hoses over Teflon (PTFE) liners like your brake hoses.

Replacing metal tubing brake plumbing with "steel braided" hose is insane.

Metal tubing weighs less, costs less, has a longer service life, is more resistant to road debris, and is less-likely to be damaged by failure-to-properly-secure.

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What happens when those filters get damaged by contact with the ground? Doesn't look like they're protected by being above the frame-rail aside from a thin-steel guard attached to the frame.

Rotors are are massive and HEAVY!
According to my '97 C/K service manual, they're 3/4 to 1 inch smaller in diameter than the JF9 C3500HD rear rotors, and probably not as wide, either. JF9 rotors = 13.58 diameter, 1.435 thick.

You haven't said which calipers you're using, but the web site brags-up their "ElDorado" calipers which are puny junk for an application like this. The JF9 rear discs use Bendix single-piston calipers, but the service manual doesn't specify how big the piston is.

The issue with mine was keeping them in operating order. I coated everything in anti-seize as far as adjusters and bleeders still ran into issues whenever I needed to work on the system.
1. Anti-seize is an improper "lubricant" for drum brake adjusters. The metal powder in anti-seize is abrasive. No wonder you had problems with them.

2. How are the bleeder screws on wheel cylinders any more prone to corrosion than bleeder screws on calipers?

I wanted to grab a rear from an HD C3500 as they come with discs.
No idea how that fits a non-C3500HD truck. May have been a nightmare. Probably easier to get a disc-swap or an axle-swap from a newer-generation 3500. I don't know how easy it would be to install, but at least the caliper would be supported properly instead of those damned flat-brackets; and the calipers and rotors would have been sized properly for the vehicle.
 
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someotherguy

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No idea how that fits a non-C3500HD truck. May have been a nightmare. Probably easier to get a disc-swap or an axle-swap from a newer-generation 3500. I don't know how easy it would be to install, but at least the caliper would be supported properly instead of those damned flat-brackets; and the calipers and rotors would have been sized properly for the vehicle.
Nevermind the width issue as the 3500HD being a C&C model has about an 8" narrower rear end than a regular dually. There's all kinds of "not gonna work" in that idea, beyond the 10x7.25" bolt pattern on the wheels.

Richard
 
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