70 Jimmy drum to disc conversion

[Gundy]

I have a 70 Jimmy with drum front brakes and would like to convert to disc. I have found conversions for the rear but not the front. I am assumming I must change front axle? I know I can put up to a 72 axle but will a 73 or newer work on my 70? Any other suggestions welcome. Thanks Gundy

 

[diesel4me]

My memory is a bit fuzzy since its been years since I had 3 of the '71-72 vintage 4x4's.
I'm pretty sure a complete front axle will fit up to '72 and the '71 & '72's had factory discs up front...pretty sure those years had flat top knuckles too,which are what everyone converting to crossover steering wants..

I'm thinking the square body front axles will also bolt in,they did change them somewhere around '77 when they changed the wheel bearings and then went to the 10 bolt "corperate" GM axle..

If I'm wrong I'm sure someone else here who knows for sure will chime in..all my trucks had disc brakes except one,a Chevelle station wagon I had,that a friend put on a '69 K10 Suburban chassis,I never had to work on the front brakes on it though--it had a closed knuckle type front axle,cant recall if it had drum brakes,pretty sure it must have..somebody here has probably converted drums to disc and will advise you better than I can about doing that..

 

[Gundy]

Thanks for the info. I would love to put a 71 or 72 axle but they are hard to find thats why I was hoping the sqaure body Blazer axle would work. Easier to find. Thanks

 

[ekajkrats]

Definitely put a wanted ad up in the classified section here on the site.

https://ck5.com/forums/ck5/parts-trucks-wanted.28/

 

[bp71k5]

You don't need a new axle, just go to the wrecking yard and pull everything from the spindle out off a later axle. It'll bolt on.

 

[ashman]

Thanks for the info. I would love to put a 71 or 72 axle but they are hard to find thats why I was hoping the sqaure body Blazer axle would work. Easier to find. Thanks

@bp71k5 is right, you don't need the whole axle. While it might be easier to just grab a full axle (assuming the gearing was the same), I'm not positive if the spring perches are the same from later model trucks. Someone else should weigh in that knows.

Either way, the outside, bolt on stuff will work just fine from any year D44.

 

[dremu]

IIRC, it's just like converting from 6- to 8- lug (or vice versa.) You change everything from the spindles out and boom, you're done.

I would stick with a Chevy D44, versus a Ford or Dodge or IH, just to keep it sort of simple for replacement parts later.

Also, you could use as a donor the later GM Corporate 10-bolt as their outers interchange with a D44. Tons of those around, from the early-80s through 87 pickups and to 91 Burbs and Blazers.

Note that 6-lug (1/2 ton) and 8-lug (3/4 ton) are different, so stick to 6-lug.

You'll also need to swap the proportioning aka combo valve, which I think on your truck is right under the master, and probably the master too. Those you just get for an e.g. '72 Blazer with disc front, boom.

-- A

 

[Gundy]

Thanks for the info!! Very helpful!