Drum to Disc questions

[Lated]

I have a 70 C10 with drum brakes on the front. I recently bought a 72 for parts and want to pull the disc brakes off of it and put them on the 70. Can I just swap spindles or do I need to use the control arms from the 72 as well? The PO told me one spindle isn't actually a 71/72 spindle, it's a 73, and I was wondering if it will complicate things any. When I go to put the new spindles on the 70 should I put the same spindles on both sides, and if so would it be better to use the 71/72 or the 73 to whenever spindles? As I'm learning more about working on these trucks I'm beginning to realize just how little I actually know. I appreciate the help.

[dave2953]

If you had 71/72 spindles I think they would bolt your control arms but the tie rods ends on your truck are different from 71/72. I think ball joints are different between 71/72 and 73 up so I don't see how you could have two different spindles.

[Lated]

I think he said it had the 73 balljoint on it too.

[st1x10]

If it is a 73 spindle you will need the balljoints and tierods. If you have all of the front crossmember from the "73" then use it. I would still install new parts on it, if they are worn out.

[Ole Blue 68]

I say go with the 73 setup. Parts are cheaper.

[Tom Vogel]

73 on is an upgrade. Thicker rotors; heavier balljoints and tie rods. Only trouble is, you will have to replace everything including and up to idler and steering arm. I did it on a 69SWB I restored.

[Lated]

Will the control arms from my drum spindles work with the disc brake spindles? The reason I ask is that the drivers side upper control arm from the disc brake truck has a hole rusted all the way through it but the control arms on the drum brake truck are in perfect shape.

[Bus Ted Knuckle]

Yes, you can use your drum brake control arm, you will need to buy the ball joints for the spindles you are using.

[Lated]

Originally Posted by Tom Vogel

73 on is an upgrade. Thicker rotors; heavier balljoints and tie rods. Only trouble is, you will have to replace everything including and up to idler and steering arm. I did it on a 69SWB I restored.

Correct me if I'm wrong, to switch to 73 up spindles I'll need new balljoints, tie rods, tie rod ends, idler and steering arms, calipers (cuz the 73 rotors are thicker), and rotors. Did I miss anything? Sounds like it would be much easier and cheaper to stick with the 72 setup for now. I think I'm gonna need a second job

[Omnivec]

Does this work for 3/4 8 lugs as well. As in can i use later year spindles on 67 drum control arms with the correct year ball joints.

[Ole Blue 68]

Originally Posted by Lated

Correct me if I'm wrong, to switch to 73 up spindles I'll need new balljoints, tie rods, tie rod ends, idler and steering arms, calipers (cuz the 73 rotors are thicker), and rotors. Did I miss anything? Sounds like it would be much easier and cheaper to stick with the 72 setup for now. I think I'm gonna need a second job

That sounds about right. If you buy all new, it's a good chunck of change.
Front end parts will run you about $250-$300 if you include the idler and pitman arm. Pair of calipers will run you about $50-60 and a pair of rotors will run $60-$90.

If you can find a front end off of a 73-87 in good shape though you can save some cash. Even the stuff that is shot, calipers for example, can come in handy for core exchanges. I paid $11.99 for my calipers with the core exchange.

[Lated]

Thanks for all the info.

[Lated]

Alright, now I have questions for the back. Since I will have 5 lugs in the front once I put the discs on I want 5 in the back too. Since I have the rear end from the disc truck I'm planning on swaping rear ends. Would it be easier to swap just the axle shafts or the whole rear end? I've never done anything with a rear end before so this is new territory to me. I'm a little nervous about popping the rear diff cover. Are the rears the same width on a '70 stepside and a '72 fleetside? If I do go the route of swapping the whole thing what's the best/safest way to remove the coil springs? Should I buy a spring compressor? I've heard of the floor jack method but I don't have one, all I have is a bottle jack so I'll have to spend cash either way and I've seen spring compressors for around $30. So... here's a recap. Should I swap just the axle shafts or the whole rear, and should I go spring compressor or floor jack method for spring removal?

[dave2953]

You don't need a spring compressor to remove the rears (or the front for that matter) Just support the rearend with jacks so the springs don't have a load on them. Then you just take the nuts loose that hold the springs in and you're in business.

[Lated]

Originally Posted by dave2953

You don't need a spring compressor to remove the rears (or the front for that matter) Just support the rearend with jacks so the springs don't have a load on them. Then you just take the nuts loose that hold the springs in and you're in business.

Wont the springs come flying out if I do that?

[dave2953]

No; if you have the rearend supported there isn't any real pressure being applied to the spring, unlike the front. You may need to loosen the rear end u-bolts (if you haven't already) to allow the trailing arm to drop. This should also relieve any additional pressure on the spring.

[68shortfleet]

Whoa, You cant support the rearend and remove the springs, they are still holding the weight of the truck up. But you still do NOT need the spring compressor.
Jack the truck up and support the FRAME and let the rearend(axle) hang freely. You may have to unhook one end of the shocks to get it to hang enough. Now you can unbolt the upper and lower spring retainer bolts. Your bottle jack could work fine for this, but make sure you have good jack stands under the FRAME.

Jason

[Lated]

How do I get the springs off the front?

[krue]

Measure the width of the 70 rear, if it's the same width as the 72, just swap the axles (70 is the yr the width changed, the only way to know if yours is the wide rear is to measure.).

[STP67-72]

You can measure length is one way. If it is a 70 model it should have three digits stamped on axle housing. Pass. side pointed towards the back window. 69 and older is HA or HC code. most of the time, unless it is a posi. The 70 and up should be stamped with 3 digits. Something like TDA, RHA or THA. If it has 3 digits it should be same width as 71-72. These digits also tells you what gear ratio was in it originally. Hope this helps.

[dave2953]

My apologies; 68 shortfleet is correct. Not sure how I came up with that one. The front springs are a little different. I set the frame of the truck on jackstands and disconnected the lower end of the shock. Loosen the lower ball joint nut a couple turns and knock the ball joint loose. Then put a jack under the control arm, take the nut the rest of the way off and SLOWLY lower the jack and remove the spring.

[dmsteele92831]

I bought my kit from Performance online, although I went with the 73 chevy kit because I needed balljoints and tierods anyway plus parts are cheaper in the future and the brakes are slightly better. But if you have a budget in mind $660.00 for everything NEW including a Booster is pretty good.

http://www.performanceonline.com/sto...at=1074&page=1

[67ChevyRedneck]

Originally Posted by Lated

Will the control arms from my drum spindles work with the disc brake spindles? The reason I ask is that the drivers side upper control arm from the disc brake truck has a hole rusted all the way through it but the control arms on the drum brake truck are in perfect shape.

Yes, the control arms will work, but you will need the correct 71/72 ball joints and other parts other's have mentioned.

As a side note, there is no difference with the upper A-arms. The lower A-arms have the bump stop for the spindles in different spots, so with the disk spindles on the drum lower A-arms, the wheel will have fewer turns from lock to lock (the wheels wont turn all the way.) I fixed this (I used 71 spindles on 67 A-Arms) by grinding the "tit" of the spindle down until the wheel turned the same number of turns lock to lock as it did before.

As far as the rearends, it would be easier to do a swap. 4 nuts and some brake line, and you're done OR, torch 'em off and buy new U-bolts