68 gmc truck brake upgrades

[jserrato714]

Hey forum what up...Its been a while since ive been here but it feels good to be home. I picked up a new project today. Its a 68 gmc short bed. It has a big v8 engine. Not sure what size.. It looks like it has a brake booster and a master cylinder but it has front and rear drum brakes. That is a first for me..I thought that the booster was for power brakes?Not sure if the previous owner before the guy that I picked it up from did this swap. Not sure if its stock either? What do I need to run disks up front? Ive done this swap before but never on a truck that had a booster in place...? please help drum brakes suck bad....If you need pics please let me know Thanks peeps

[lolife99]

Welcome back.
Look around in the suspension section.
This topic is discussd every day.
If you still have specific questions,... I'll be glad to help.

[jserrato714]

Originally Posted by lolife99

Welcome back.
Look around in the suspension section.
This topic is discussd every day.
If you still have specific questions,... I'll be glad to help.

Yeah Lolife I have searched and I can only find info on how to do the set up and whats needed(parts list). My proplem is that I cant find anything on power brakes that have front drum brakes. I dont know if thats standard. Im thinking that now I just need the upper,lower control arms,disk,spindels,brake hoses and that my current brake booster and master cylinder will work with the new set up. Please be so kind as to lead me in the right dirrection. Thanks

[lolife99]

Originally Posted by jserrato714

Yeah Lolife I have searched and I can only find info on how to do the set up and whats needed(parts list). My proplem is that I cant find anything on power brakes that have front drum brakes. I dont know if thats standard. Im thinking that now I just need the upper,lower control arms,disk,spindels,brake hoses and that my current brake booster and master cylinder will work with the new set up. Please be so kind as to lead me in the right direction. Thanks

1) No need to change control arms.
2) If you buy "year specific" 63-70 drop or regular spindles,... you can bolt them onto your current a-arms and outer tie rods.
3) You will need 1-1/4" wide rotors in 5 or 6-lug,... whichever you choose.
4)You will also need dust shields,... and calipers for the 1-1/4" wide rotors.
5) Your Master Cylinder and distribution block will need to be swapped for a disc brake master cylinder and a disc/ drum proportioning valve.
(or disc/disc version if you plan on putting rear disc brakes on).

I'm not sure about your brake booster.
I had a '69 lwb that had power drum brakes. It's not that unusual.
I guess you could try your's with the new disc brake m/c.

[jserrato714]

You are the Fn man lolife....That makes things easier..So I f I do try my booster with all my new parts whats the worst that can happen? Also..are all the og hard lines compatible with the new disk set up ?thanks a million

[N2TRUX]

Originally Posted by jserrato714

You are the Fn man lolife....That makes things easier..

That man knows his suspension stuff don't he....

[lolife99]

Originally Posted by jserrato714

You are the Fn man lolife....That makes things easier..So I f I do try my booster with all my new parts whats the worst that can happen? Also..are all the og hard lines compatible with the new disk set up ?thanks a million

You will have to remake 1 front and 1 rear line at the least.
You'll need to connect the front line fron the prop. valve down to the tee on the backside of the front crossmember.
The other one, is the the rear line out the back of the prop. valve that goes to the rear axle.
On my blazer,... everything was rusted solid.
I replaced all the steel lines.
The rubber hose-to-steel line connection can be a pain also.
Use a little heat (propane torch should do it), and some penetrating oil.
Also a LOT of paitience.
Work the fittings back and forth and you should be able to save them. Otherwise you will twist the steel tube nuts off or kink the tubing.

[jserrato714]

Oh I see...Ok I think I will tackle the job this weekend. Its 50% off all parts at the local wrecking yard in cali this week. Thanks 4 the help.