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Discussion Starter #1
I have a 95 K2500 FF 14 bolt SRW with the press on drums, NOT the slide on drums.
Apparently Chevy used the press on style-old style drums along with the slide on-new style for several years.

Got the MotoBilt bolt on brackets and do not seem have enough clearance to get the caliper with the pads on.
These, (1) 14 Bolt Full Float Disc Brake Conversion Brackets – Motobilt

I have just under 5/8" clearance between the caliber bracket and the disc.
Anyone know what the clearance should be and why I am having issues?

Trying to get this together tonight.
Thanks!
 

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blatant asshole
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Need a picdoesnt say which model axle those fit but the off set looks to far for stud retained discs.
 

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Discussion Starter #3
Well it is outside, in the dark and tarped for the night so a pic will have to wait.
The bracket is 3/8" thick and has about a 7/8" offset.
So say if I needed 1" clearance between the bracket and disc I should have only a 1/2" offset instead of the 7/8".

The discs, calipers are all typical 73-87 K20 stuff.

I now see Roughstuff says about their brackets, "These will only work on a 73-87 axle, the newer axles are hit and miss."
I am thinking it is a miss on mine.
 

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Discussion Starter #5
0.855" offset, call it 7/8". That is probably the problem.

You think that one of these plate fabbers would have dimensions posted, say from mounting face of plate to inside face of the disc or the hub's disc mounting face to sort all this out and get the right offset for the application from the get go.
But none seem to.
Or even the offset of the plates they are selling.

Guess I will be calling Motobilt in the morning. Ugh, another week this project doesn't move forward.
 

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Discussion Starter #6
Found this on RS's site.
Our disc brake conversion kit is the best conversion to eliminate the drum brakes on a full float 14 Bolt Rear Axle. The 14 bolt axle is common in Chevy / GM fullsize trucks from 1972 until today in the 3/4 ton and 1 ton range. Changing from drum brakes to disc brakes is easy, and all the parts you need to complete the conversion are included in this kit to get rid of those heavy drums brakes. These will only work on a 73'-87' axle the newer axles are hit and miss. To double check, measure from the 4 bolt mounting flange to the surface the wheel studs press up against (back of hub), should be about 4 11/16"

Mine looks about 4-3/4 close enough 4-11/16".

RS video appears to show about the same 7/8" offset as mine.
RuffStuff Specialties: 14 Bolt Disc Brake Brackets for Single Rear Wheels (SRW)
 

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Keep in mind the 14FF came in a few flavors (hub differences etc) I know RS had to be corrected way back when coming out with their bolt on brackets....a 14FF C&C required different brackets. That MB description is rather vague.....
 

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Discussion Starter #9
Pics of issues, less than 5/8" between bracket and caliper.


3113310





Pad won't even fit in by itself.

3113311


Bracket is mounted tight and true.

3113312
 

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Discussion Starter #11
It is the stock SRW hubs and axle as far as I know.
It is on a typical 95 K2500 and had a regular bed on it when I got it.
Yes, close to the spring pack. The bracket can only go on in 1 reasonable position because you can't put the caliper bolts in otherwise.
 

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^^^ Yes, I run the C&C rear (w/the C&C/DRW hubs) and brackets from RS. I now see in the pic the SRW style hubs. Hard to tell in the pic, but mount the caliper (if you haven't already) and see if pad fits onto caliper pin/bolt and clear the rotor. The pads "fatness" doesn't go between the bracket and rotor...if i recall the pad fits between the caliper pin span of the bracket. To get a good look i'd have to go take a wheel off...and I am being lazy 😆 Not sure if I described that clear enough?
I have 3/16 to 1/4" space between the backside of the pads backing plate and bracket. The backing plate doesn't lay against bracket.
 

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blatant asshole
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The pad has to fit between the bracket and the rotor. It rides on the pin inside of the bracket.
 

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Discussion Starter #15
^^^ Yes, I run the C&C rear (w/the C&C/DRW hubs) and brackets from RS. I now see in the pic the SRW style hubs. Hard to tell in the pic, but mount the caliper (if you haven't already) and see if pad fits onto caliper pin/bolt and clear the rotor. The pads "fatness" doesn't go between the bracket and rotor...if i recall the pad fits between the caliper pin span of the bracket. To get a good look i'd have to go take a wheel off...and I am being lazy 😆 Not sure if I described that clear enough?
I have 3/16 to 1/4" space between the backside of the pads backing plate and bracket. The backing plate doesn't lay against bracket.
I can't assemble the pads and caliper and slide them in place. Not near enough space.
Can put the caliper in place w/o the inside pad.

I have been talking to Motobilt, they say the brackets should be 7/8" offset which they are.
They are confirming I used the correct rotors and calipers.

I have double checked I have the right rotors, ACDelco 18A61A, GM 19296944, which say 71-86 K20.
Calipers are the H/D ACDELCO 18R650 and ACDELCO 18R649, which say 79-86 K20.

Still baffled.
 

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Ok, I see it now. Your ears looked offset for some reason in your pic. I have 3/4" between bracket and rotor. Again, I haven't had looked at this in a long while...been issue free. IIRC rear Caddy Eldorado pads are a little thinner but same ears...try those? A pic of mine for reference....I decided to not be lazy and take a look...lol
3113352
 

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blatant asshole
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Idk wtf they got that number from but its to deep and not the standard offset that anyone else uses for stud retained drums.

Money says those brackets are for slip on drums and sliding the same rotor over instead of back side.
 

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blatant asshole
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Ok, I see it now. Your ears looked offset for some reason in your pic. I have 3/4" between bracket and rotor. Again, I haven't had looked at this in a long while...been issue free. IIRC rear Caddy Eldorado pads are a little thinner but same ears...try those? A pic of mine for reference....I decided to not be lazy and take a look...lol
View attachment 3113352
Before the standard was figured out a lot of guys just took the pad to the belt sander
 

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Discussion Starter #20
Idk wtf they got that number from but its to deep and not the standard offset that anyone else uses for stud retained drums.

Money says those brackets are for slip on drums and sliding the same rotor over instead of back side.
OK, RS says the offset with a 3/8" plate, the offset should be 0.780" ish for 'standard' brake backing mount to disc mounting surface of 4-11/16". That is what RS says should be the number.

4.687-0.375-0.780 = 3.533" minus my total disc width of 2.810" = 0.722" between the bracket and rotor.
I have less than 5/8 or 0.625.

So I am not missing it by much, 0.100" to 0.150"??, but obviously enough that I can't assemble it.
Not grinding off the pads, I will buy the right bracket or make one.
 
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