Disc brake conversion help.

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Charlie Kleman

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So kind of a weird issue here, I didn’t see anything about this in any other threads. Doing the disc brake conversion and everything went together great until I went to put the hubs/rotors back on the axle. Both sides need to go on like a 1/4-1/2 inch farther. All the bearings and races in the hub seem to be seated correctly. Had each one on and off a few times and I’m totally stumped, not sure if anyone has ever had this issue or any suggestions. Below is a picture of how far I could get the driver side hub/rotor on. And a couple of the best pictures of inside the hubs I could get if that helps at all. Thanks!
 

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PrairieDrifter

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Did you ever check to see if your bearings fit the spindle correctly, before you put them in the hub? If you're positive the races are seated then I would think wrong bearings.
 

Charlie Kleman

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They looked identical when I had them side by side, but I never actually put the new ones on the spindle so I guess that’s possible. Might just have to take everything apart again
 

Rusty Nail

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So kind of a weird issue here, I didn’t see anything about this in any other threads. Doing the disc brake conversion and everything went together great until I went to put the hubs/rotors back on the axle. Both sides need to go on like a 1/4-1/2 inch farther. All the bearings and races in the hub seem to be seated correctly. Had each one on and off a few times and I’m totally stumped, not sure if anyone has ever had this issue or any suggestions. Below is a picture of how far I could get the driver side hub/rotor on. And a couple of the best pictures of inside the hubs I could get if that helps at all. Thanks!


If you use split warshers there you will be sorry. Make certain to get the correct hardware for that job... I sourced parts from an aircraft repair place cuz it was tuff to find

The Right Stuff.

xc_hide_links_from_guests_guests_error_hide_media


Look on the google maybe that will help too.


You must be registered for see images attach



:waytogo:
 

Grit dog

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^Whats the issue with lock washers for the caliper bracket?
Note those bolts are one of the few places I’d use loctite on a car.
 

Rusty Nail

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M
^Whats the issue with lock washers for the caliper bracket?
Note those bolts are one of the few places I’d use loctite on a car.
Wrong application for split washers.

Without typing a book..they will loosen. And split. Not really much of a warsher at all. It is important to understand that the effectiveness of split lock washers is very low or nonexistent when used with heat treated fasteners of 8.8 (Grade 5) and higher. The spring rate of the washer is too low, and the edge of the washer will not dig into the hard fastener surface.



Hope this helps!
 

Grit dog

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Wrong application for split washers.

Without typing a book..they will loosen. And split. Not really much of a warsher at all. It is important to understand that the effectiveness of split lock washers is very low or nonexistent when used with heat treated fasteners of 8.8 (Grade 5) and higher. The spring rate of the washer is too low, and the edge of the washer will not dig into the hard fastener surface.



Hope this helps!
Makes sense. Now that I think aboot it. I’ve seen them spread or split in 2 pieces.
 

Rusty Nail

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Split washers are really easy to find and ye old local faster supply place may not even be there anymore...depot dont got no flat warshers - go look for yourself if you must. :)
Airplane supply is a really good tip imo.
(worked for me - now it's all serviceable and stuff)

Reckon a split warsher would be one time use? If all that stuff is true anyways.. :shrug:


Looked through my 1977 C20s thread to page 14. Found some pix. Remember how unhappy I am with that...

Check out the tire carrier @AyWoSch Motors :D
 

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Rusty Nail

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This really boils down to crappy caliper brackets I reckon. You'd think there oughta be a better way to do this by now.
Not happy with mine at all obviously having to use warshers is the suck.
Whatever junk i used is not the right stuff either.

Y U NO HAZ UPDATE @Charlie Kleman ?
 

wlwarnke

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They do make special 3 bolt shims to space the caliper brackets. Mine came with welded on standoffs that were too tall and I had to take 1/8” off. Sounds pretty common to have to make adjustments.

Don’t forget the disc/disc Prop Valve (PV4 I think). Even with 35s, my K5 would lockup the rears prematurely with an Oh **** stop on dry pavement. Even worse in the rain.
 

70SBUDGET

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are these a direct swap from another vehicle or an after market kit? I see the 8 lug which i also have so super curious.
 

Rusty Nail

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Nah @70SBUDGET it's alleged to be simple. Pull the hub off your axle , swap in the fancy caliper bracket.
Chances are you can use parts off the same year 4x4 truck so you end up using 4 front calipers.
You gotta MAKE the rear lines annnd voila!

:33:

If I had it all to do over again I would rebuild the drums in a heartbeat.
 
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Rusty Nail

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let me talk you out of that, the rear disc swap aint all it is cracked up to be.

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70SBUDGET

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Nah @70SBUDGET it's alleged to be simple. Pull the hub off your axle , swap in the fancy caliper bracket.
Chances are you can use parts off the same year 4x4 truck so you end up using 4 front calipers.
You gotta MAKE the rear lines annnd voila!

:33:

If I had it all to do over again I would rebuild the drums in a heartbeat.

bending lines is teadious and a headache but in the end is pretty easy. the thought of 4 fronts seems unbalanced and overbuilt in my brain. i swapped the rears on my 70 camaro and the size difference was impressive but they were balanced. im guessing the large size locks up the back pretty easy?
 

Rusty Nail

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/shrug.
Dont drive the truck but probably.

*edit
to be more clear ; the rear calipers I used are same year front calipers for a 4x4 Ktruck.
:waytogo:
 
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