Front disc brake swap

[Jl8806]

I know there's a million threads out there on this but I can't seem to find the answer I'm looking for. I have a 68, if I buy some of the stock height spindles that everyone sells for their disc brake conversion kits, can I go to the parts house and buy hubs/rotors, calipers, pads etc for a 71-72, is the caliper bracket made on to the spindles? I'm all for buying spindles I'd just like to be able to go to the parts house when I needed replacement brake parts instead of having to order them...

[notsolo]

Regular height or drop spindles gets you started, disc bracket is on the spindle. Parts house or somebody like Rockauto gets you the rest of the parts.

[Jl8806]

So could I use these and just swap my ball joints and tie rods out for 71-72?

http://sokyclassics.com/product.php?skcid=1002811

[GMCPaul]

You need the spindles + front disc brake conversion hoses. If you get the spindles designed for 1964-70 trucks for 12" rotor disc conversion no need to swap anything if you get the 71-72 spindles you need to swap to 71-72 ball joints & 71-72 outer tie rods and then you'll also need adapter sleeves for inner tie rods to adapt the outer 71-72 tie rod to the inner 67-70 tie rod as you can't use the 71-72 inner tie rod with the 67-70 drag link.
When you get bearings, seals, rotors, calipers, pads order for a 71-72
If you order the 73-87 versions you quite often end up with 10mm banjo bolt calipers being in the box if you order wrong year ( 73-78 were 7/16" and 79up were 10mm ) as they often get boxed wrong we've seen at the auto parts stores, where as 71-72 calipers are 7/16" banjo bolts.
Paul Jr @ GMCPauls

[Jl8806]

What if I was putting all new front end parts anyways? Are there any hubs that will work on those spindles that are 6 lug?

[GMCPaul]

The hubs are a integral part of the rotor and can not be separated from rotor. So when you buy the rotor it comes with hub built in. The 6 lug conversion rotor and 71-72 5 lug rotors both use 71-72 bearings & seals, the only difference between them is the bolt pattern for wheels.

If your replacing front end parts anyways why change to the later model instead of replacing with new 67-70 parts if you don't have to when you get the 64-70 conversion spindles? Then you don't have to worry about keeping track of which parts are 67-70 and which are 71-72 on steering and brakes both and the next person that has to replace parts on truck isn't stuck trying to figure out what parts are what when they need replaced next. If you want to keep 6 lug pattern then you have to get conversion 6 lug rotors which aren't available from your local auto parts stores.
Paul Jr @ GMCPauls

[rpmerf]

I am doing the conversion on my 1970 C20. I picked up a 1983 C20 with no engine or trans to use some parts off of. I liked this option, because most of my steering and front brakes will be 1983 parts. I also like that this uses factory parts, and not conversion parts. I can buy everything off rock auto aside from the the spindles, center link, and prop valve.

Here are the parts I am using from the 1983.
Spindles - Used
Center Link - Used
Proportioning valve - Used
Dust Shields - Used
Upper and Lower Ball Joints - New
Tie Rod Ends - Inner, Outter, Adjusting Sleeve - New
Idler Arm - New
Calipers - Used as long as they look good, available on Rock Auto
Rotors - Used as long as they look good, available on Rock Auto
Pads - Used as long as they look good, available on Rock Auto
Caliper Hoses - New
Master Cylinder - New
Wheel Bearings - Used, repacked as long as they look good, available on Rock Auto
Wheel Seal - Used as long as they look good, available on Rock Auto
Spindle Nut + washer - Used as long as they look good, available on Rock Auto
Dust Cap - Used as long as they look good, available on Rock Auto

I also plan to do the control arm shafts while I am in there. The pitman arm was replaced about a year or 2 ago, so I will leave that. I believe the 71-82 uses the same idler arm, but the size changed in 83.

If you have the stock 4.5 turn box, a 73-87 3.5 turn box is a nice upgrade. When I installed the pitman arm, I installed a 3.5 turn box, so that will stay. If you use a 73-87 steering box, you will have to look up how the lines match up. I believe 73-77 is drop in. 78-87 needs conversion lines for metric threads, or a matching pump. Not 100% on this conversion.

Another thing to consider is prop valve location and brake lines. You have a couple options here. My 70 has the prop valve under the master cylinder with 1 front line that is teed out to the front drums. The 83 had the prop valve under the radiator with individual front lines. You can use the disc prop valve under the master and plug one of the front ports. If you choose this option, there may be an issue with rubber lines. I plan to install it as it came out of the 83.

There were different braking systems over the years. In the 80's there was JB6 and JB7. JB6 was the standard braking system. JB7 had thicker rotors, larger calipers, and a larger master. Can't remember the differences in the 70's braking systems.

[Jl8806]

Yeah you're right, I really want to keep it as stock as possible which is why I would like to use the spindles and 71-72 brakes but then at the same time I hate to have 5 lug on the front and 6 on the back... I plan on making it into a 71-72 as far as the looks go

[Jl8806]

Originally Posted by GMCPaul

The hubs are a integral part of the rotor and can not be separated from rotor. So when you buy the rotor it comes with hub built in. The 6 lug conversion rotor and 71-72 5 lug rotors both use 71-72 bearings & seals, the only difference between them is the bolt pattern for wheels.

So could I possibly use 90s model Chevy 2wd 6 lug hubs with 71-72 bearings? I'm just wonder where all these companies are sourcing the hubs/rotors from that have 6 lugs on those spindles, I have a scare bird kit for our other 68 and it says to use those rotors

[Grumpy old man]

6 lug rotors/ bearings from Summit , dust caps from autozone . All Moog suspension parts from Rockauto . brake lines from Autozone ,splash shields from Ebay , this is on a 67 , all suspension is 67 brakes are 71 Or just buy a conversion kit ,

[Jl8806]

Originally Posted by Grumpy old man

6 lug rotors/ bearings from Summit , dust caps from autozone . All Moog suspension parts from Rockauto . brake lines from Autozone ,splash shields from Ebay , this is on a 67 , all suspension is 67 brakes are 71 Or just buy a conversion kit ,

So your spindles are the 67-70 disc brake spindles that everyone sells? Also what 6 lug rotors and bearings do you order? Where did you find your control arms? I've found some lower but can't find the uppers

[Grumpy old man]

Mine are CPP drop spindles ,The stock spindles are available . I ordered thru Summit for free shipping , You don't change the control arms . You buy conversion spindles that use the early ball joints .

http://www.classicperform.com/Store/...062SWBK5OE.htm

[Grumpy old man]

Your in Kentucky call Southern Kentucky Classics .

http://sokyclassics.com/

[Jl8806]

Originally Posted by Grumpy old man

Mine are CPP drop spindles ,The stock spindles are available . I ordered thru Summit for free shipping , You don't change the control arms . You buy conversion spindles that use the early ball joints .

http://www.classicperform.com/Store/...062SWBK5OE.htm

I just thought your control arms looked new is the reason I asked, I want to put everything new I can

[Grumpy old man]

Originally Posted by Jl8806

I just thought your control arms looked new is the reason I asked, I want to put everything new I can

Media blasting /prime and paint ,Lots of elbow grease .

[GMCPaul]

Originally Posted by Jl8806

So could I possibly use 90s model Chevy 2wd 6 lug hubs with 71-72 bearings? I'm just wonder where all these companies are sourcing the hubs/rotors from that have 6 lugs on those spindles, I have a scare bird kit for our other 68 and it says to use those rotors

No you can not use any off the shelf rotor that was made for another application, the current 6 lug rotors are being manufactured by the same company that makes the stock 5 lug 71-72 and 73-87 rotors. Instead of drilling the 5 bolt pattern they instead drill the 6 bolt pattern. None of the standard auto parts stores stock the 6 lug version because it does not have a original GM application.
Paul Jr @ GMCPauls

[Jl8806]

Originally Posted by GMCPaul

No you can not use any off the shelf rotor that was made for another application, the current 6 lug rotors are being manufactured by the same company that makes the stock 5 lug 71-72 and 73-87 rotors. Instead of drilling the 5 bolt pattern they instead drill the 6 bolt pattern. None of the standard auto parts stores stock the 6 lug version because it does not have a original GM application.
Paul Jr @ GMCPauls

But I can use the 71-72 rotors on the aftermarket spindles as long as I'm ok with having 5 lug on the front right?

[GMCPaul]

Yes, you can use the 71-72 rotors as long as you are all right with having a 5 lug front end.