C30 Disc Brake Swap

[muleys67]

Hello. Ive got a 69 C30 Id like to put disc brakes on it.If I had a 73-87 C30 for parts is this a direct swap? Rear axle swap also.The leaf springs on the 69 are broken,needs wheel cylinders,probably shoes.I dont plan on putting a lot of cash into this truck other than mechanical upgrades. Im thinking I can get a late model c30 cheap at a local jy.Any help is greatly appreciated.Muley

[SCOTI]

Originally Posted by muleys67

Hello. Ive got a 69 C30 Id like to put disc brakes on it.If I had a 73-87 C30 for parts is this a direct swap? Rear axle swap also.The leaf springs on the 69 are broken,needs wheel cylinders,probably shoes.I dont plan on putting a lot of cash into this truck other than mechanical upgrades. Im thinking I can get a late model c30 cheap at a local jy.Any help is greatly appreciated.Muley

The front disc swap is straight forward like it is w/the smaller C10's.

On the rear, I'm not sure on the C30's but pre-73 C10's had narrower leafs. Measure the width of the leafs to be sure. Also measure the width between the spring perches from the current rear end so you can compare w/possible donors.

I have an 89 & could get you the spring pad dimensions within a day or 2.

[muleys67]

Hello,Scoti.Id appreciate the info.Im hoping the later year stuff will work for the availability of parts.My c30 doesnt have an engine yet.If I had a place to store it I would remove the flat bed."If I move this over there and put that here then slide that..."
Thanks again.Muley

[ColumbianIndian]

I know I am a little late but I haven't found much on this or any other site for the C30. I have a 1970 GMC 3500. Wood bed single axle (Eaton H072). I here is how I did the disc conversion

1985 - 2500 Spindles (junk yard)
1972 - 2500 Top and bottom ball joints (auto zone)
1972 - 2500 inner outer tie rod and sleeves (auto zone)
1972 - 2500 caliper pads, brake hoses, rotors, inner and outer bearings(auto zone)
1972 - 2500 booster master cylinder (auto zone)
1972 - 2500 proportioning valve and mounting bracket (Inline tube)
1972 - 2500 front brake lines (inline tube)
1972 - 2500 longhorn front to rear line (inline tube)
1970 - 3500 dually rear axle line (inline tube)
1970 - 3500 shocks (auto zone)

Also you will needs new lug nuts the thread is different on the 72 rotors.

[Badazzbuckeye]

I have a 67 c-20. Would this work on it? Do you have to change control arms? Or juest the ball joints and such?

[Vova]

If you need I have 71-71 C20 2.5" drop spindles for sale. I believe they are the same for the C20 and C30.