Disc Brake conversion... a little help.

[~Whitey~]

I have a 69 c10 that I'm wanting to do a disc brake conversion on... During the conversion I am wanting to add in some 2.5 inch drop spindles. LMC has drop spindles for 67-70 and 71-72. I've research the boards here on this as best as I could and have come to the understanding that the 71-72 trucks lower arms use a little bit bigger ball joint... ???

Here's what I have in parts acquired for this conversion taken from a 72 c10 truck:
Upper and Lower arms
Calipers
Rotors
Stock Spindles
Master Cylinder & Booster
Proportioning Valve
Drag Link and Tie Rods

One again my truck is a 69 c10

Questions:
Should I use both the upper and lower arms from the the 72?
Or is the upper arms the same for all years on the c10's?
If I use the 72 lower arms then I assume when I purchase the drop spindles I should get the ones for 71-72 trucks ??

Thanks in advance fellas and sorry if this has been answered somewhere else already... love the site and I get ALOT of inspiration here.

[shaggi01]

I'm doing a disc brake conversion on my 70. From what I've learned, the control arms are the same. But the ball joints are different. You will also need new rubber line from the steel lines to the calipers, unless you change the hard lines also.

[~Whitey~]

thanks shaggi01 Yeah I'd planned on changing the rubber lines... Didn't know it was just the ball joints that are different. Read somewhere on here where someone had said to use the lowers from the 72, but maybe they were talking if you weren't going to change the ball joints. ..

[shaggi01]

Glad I could help. ECE has the conversion rubber lines for $55.00.

[lolife99]

Originally Posted by 69swb

I have a 69 c10 that I'm wanting to do a disc brake conversion on... During the conversion I am wanting to add in some 2.5 inch drop spindles. LMC has drop spindles for 67-70 and 71-72. I've research the boards here on this as best as I could and have come to the understanding that the 71-72 trucks lower arms use a little bit bigger ball joint... ???
The 3/4 ton trucks have a bigger ball joint hole in the lower a-arm.
All 1/2 ton 67-72 upper and lower a-arms are the same.

Here's what I have in parts acquired for this conversion taken from a 72 c10 truck:
Upper and Lower arms
Calipers
Rotors
Stock Spindles
Master Cylinder & Booster
Proportioning Valve
Drag Link and Tie Rods

One again my truck is a 69 c10

Questions:
Should I use both the upper and lower arms from the the 72?
Yes,... if you plan to use 71-72 spindles, and NOT change the balljoints.
Or you can install whatever year balljoint in your original a-arms.
Balljoints have to match the spindles.

Or is the upper arms the same for all years on the c10's?
Yep. 67-72 1/2 ton and 3/4 ton upper a-arms are all the same.


If I use the 72 lower arms then I assume when I purchase the drop spindles I should get the ones for 71-72 trucks ??
Like I said above,... it's the correct year balljoint that has to match the spindle,... not the a-arm.

Thanks in advance fellas and sorry if this has been answered somewhere else already... love the site and I get ALOT of inspiration here.

See answers above.^^^
The biggest news in 67-72 drop spindles,... is the aftermarket developing "year specific" drop spindles.
They now make a 63-70 spindle that would bolt directly on your truck without robbing parts from a donor truck like you did.
Unbolt your drum brake stuff,... and bolt on the new disc brake spindle.

You will still need a 71-72 M/C and prop valve.
(or any of the aftermarket parts that are now available).

Look here for more info:
http://67-72chevytrucks.com/vboard/s...68&postcount=4

[~Whitey~]

Thank you Keith! That exactly what I needed to know. Jimmy
Posted via Mobile Device

[lolife99]

Got any more pics of your truck?

I just noticed you were in Springfield, MO.

[~Whitey~]

There's a few more in my album here: http://67-72chevytrucks.com/vboard/a...p?albumid=1547 that's all I've uploaded at this time. I'm going to start a build thread... It's a good solid truck with very little rust, I've have another set of doors that I am working on right now, figured I get those out of the way first, then I'm pulling it in the garage and going to take it down to the frame and work my way up. I'm really excited to get started on this, bought the truck about a year ago and have just been enjoying driving it.. hate to park it, but I guess that'll give me incentive to work on it often. ;-)

[michael bustamante]

good lookin truck. I did this conversion not too long ago. You need to replace lower ball joints to existing a arms, replace the steering rack with a 71-72 rack due to center link is different Ive been told, I replace the tie rod ends also. (theyre different from the 69)
brake hard lines are different as well and since youre not replacing the lower control arms youll notice the brake line mounting tab is in a different location. I cut mine off and welded it to the 71-72 location. replace the master cyl and prop valve too and the rear line will not fit in the disc/drum prop valve so you have to make an adaptor from brass fittings found at napa.
Hub bearings, and rotors, i believe are 71-72 only.

[~Whitey~]

Thanks Michael .. since I have the uppers and lowers from the 72.. I'm going to go ahead and clean them up to use so I can keep driving the truck as long as possible. :-)

[weaintscared]

I'm using the whole cross member,A frame hib to hub from a 72 on my 69
I hope it bolts right up.

My build

http://67-72chevytrucks.com/vboard/s...d.php?t=468622

[droppedgmc]

check this thread on a 69' I did. it already had a 71-72 disc swap.
http://67-72chevytrucks.com/vboard/s...d.php?t=457180

[lolife99]

Originally Posted by weaintscared

I'm using the whole cross member,A frame hib to hub from a 72 on my 69
I hope it bolts right up.

No need to change the entire crossmember.
Just take everything from the a-arms out.
No need to mess with the engine or the frame mounts.