Smaller/thinner rear brake drum? Deep rear steelies won't fit!

[Just call me Sean]

This is a drum from my G20. It doesn't look as thick on the face as yours. Has the 2 3/4 brakes.

[mongocanfly]

Spartan locker is basically what's called lunchbox locker..it replaces the spider gears in a standard diff..
10 and 12 bolt rear have C clips that hold the axles in...you'll have to disassemble the spartan to get the axles out

[SCOTI]

Originally Posted by vintage_mpg

So there's a salvage yard within a mile of my house; I'll swing by there tomorrow, hopefully, to take a peek at some trucks to see if they might have a complete rear-end setup with the smaller brakes.

I have a few questions, though....

1) This rear end is a 12-bolt with a Spartan locker. I'm not sure how that works; anyone with any experience there? I looked up several youtube viddies on how to remove axles from a 10-bolt, but haven't looked up the 12-bolt yet. Are they the same? Even with the Spartan locker?

2) Will swapping from the 2 3/4" brakes to the 2" rear brakes impact any part of the rear axle fitment? Meaning.....when I remove 3/4' of the brake width (swapping from the 2 3/4" wide shoes to the 2" wide shoes), does that play into the length of the axles, brake drum, etc? Or will it all come together just fine? Or will the axles now be 3/4" strong on the ends? I'm guessing it will be fine...but this is all new for me, so I'm trying to think ahead

3) Are the rear brakes the same (meaning 2" brakes) for a 10-bolt as they are for a 12-bolt? I have a feeling I might only find the 2" brakes on 10-bolt rear ends, and the 12-bolts will all have the 2 3/4" shoes. Just an assumption on my part, but being that the 2 3/4" are heavier duty brakes, seems they'd all be found on 12-bolts....but maybe that's not true at all.

I'm going to go poke around in the salvage yard/boneyard to see what I might discover. They usually have a decent selection of old stuff....but it's getting thinner and thinner each time I go looking for older stuff. I just want to put eyes on a 2" rear brake setup, hopefully from 12-bolt rear-end. Maybe I can buy backing plates and springs/other hardware from the boneyeard, then get some new shoes and drums to complete the swap.

Thanks for all the positive input! I've never busted into my own rear diff, so this is uncharted territory for me. I wouldn't even consider it if it weren't for your comments and encouraging remarks - so THANK YOU!

The axles are the same length specific to the housing.

You can take a HD drum set-up & install it on another standard 12-bolt housing or even one of the earlier pre-70 housings. The brakes swap over as an entire set-up which requires the backing plate that have a deeper offset which provides room for the wider shoes/drums w/o impacting axle/rear housing width requirements.

As for doing the work.... Start off by helping yourself. Practice first. Take the rear wheels off & remove the drums. Take one side apart to help understand what to expect (tension/force/effort). When everything related to the brakes is apart, put that side back together. You'll be able to reference where things go by looking @ the opposite side. Make sure you can complete the diassembly/reassembly process before advancing to removing axles & brake backing plates.

Even when you do the actual swap, do one side @ a time. It'a always a benefit for the novice to have a visual reference to work with.

[vintage_mpg]

Originally Posted by Just call me Sean

This is a drum from my G20. It doesn't look as thick on the face as yours. Has the 2 3/4 brakes.

Boy...I agree. I think your drums don't have that taller outer lip like mine.

We'll know more once the part arrives. Fingers crossed!

[vintage_mpg]

Originally Posted by SCOTI

The axles are the same length specific to the housing.

You can take a HD drum set-up & install it on another standard 12-bolt housing or even one of the earlier pre-70 housings. The brakes swap over as an entire set-up which requires the backing plate that have a deeper offset which provides room for the wider shoes/drums w/o impacting axle/rear housing width requirements.

Right on. This is good info!

Thank you for that input....

[Corts60]

Grinding on the wheel instead of solving the fitment issue correctly seems a bit crazy to me. But to each their own.

[vintage_mpg]

Originally Posted by Corts60

Grinding on the wheel instead of solving the fitment issue correctly seems a bit crazy to me. But to each their own.

I'm with ya; it would definitely be a "last resort" option....

[ShortHaul]

Originally Posted by vintage_mpg

I'm with ya; it would definitely be a "last resort" option....

So I've had this EXACT problem you're dealing with here... I had a 70 SWB that had a 5 lug rear end swap, turns out it was out of a squarebody with a big brake (2 3/4") system... I bought the 15x10 wheel vintiques steelies and was dead set on running them... I went through just about every option you've described, spacers, grind down the drums, spend an arm and a leg on a whole new rear end... etc etc.

What I ended up going with was replacing the brakes, from backing plate to drum, with a set of smaller 2" wide 5x5 drums off a 71-72 (and maybe on up to 73+) I have it all written up here.

http://67-72chevytrucks.com/vboard/s...d.php?t=766038

Basically the hardest part was sourcing the backing plates for the smaller drums. Literally every other part of the brake system is available from NAPA...

I got new backing plates from a member on here, and bought the rest of the parts new and swapped it all. Bolted up fine and mounted those badass 15x10's and never looked back.

Good luck, let me know if this helps or if you have any questions.

[SCOTI]

It should be easier to find a 12bolt 5x5 pattern w/standard brakes than it is to find one w/HD brakes.

Perhaps there's even a board member that would be interested in a straight up swap??

[vintage_mpg]

So I swapped drums...and I think I'm good to go!

Only able to find one rear drum at this point...but another is supposedly on the way.

Check it out:

[mongocanfly]

like it!!!!...so you only changed the drum?..what was the difference?

[vintage_mpg]

Originally Posted by mongocanfly

like it!!!!...so you only changed the drum?..what was the difference?

Yep - I swapped the rear drums as @Nick_R_23 suggested....and they just - fit. Tucked right in.

The fronts took a 1/4" spacer, which I didn't anticipate....but they kept kissing the tie rod ends. The spacer took care of that, as far as I can tell. I give up 1/4" of wheel stud length - is that anything I should be concerned about? It's not ideal, I realize...but there is still a good 3/4" - 1" of thread sticking through the wheel. Think that's sufficient? With the tapered acorn-style lug nuts? Thanks @ShortHaul for his thread that chased down the same issues! The spacer worked for my fronts as well - so much appreciated.

I have yet to take it for a drive, so I may be celebrating a bit prematurely, but so far they all look like they're going to work! Wahoo!

I may need to put her on the road for a day or two to see what shakes out, but so far I'm feeling very positive. And it looks absolutely killer! More pics to come...

Thank you so much for everyone's help! I love this place!

[vintage_mpg]

So I finally got the wheels and tires sorted out....and took her for a shakedown run this morning and found her pouring fuel from the dual-tank valve. Awesome. Haha. Three steps forward, two steps back.

It's the single-wire, 6-port valve. Guessing those are almost impossible to find these days?

This is going to take a new thread, most likely! Haha. Darn trucks!