"Drum to Disc" conversions 67-70 pics and videos

[Gregski]

the lower control arms were next, for this you will need a socket that is always one size bigger than the biggest you got, ( aka 1-5/8" ) ha ha

don't be too proud to use a cheater bar, but do it when yer fishin' buddies aint lookin'

Top Tip: once you get a turn or two in and can see a row or two of threads, please spray it with some PB Blaster (no not WD-40 that ain't penetrating oil, nor cutting oil, don't get me started, ha ha) and then, SCREW IT BACK IN, say what? No way man, we worked too hard to get it out this far, trust me, screw it back in and she'll come out like a hot knife through butter.

[Gregski]

getting one side of the lower control arm rod off is easy as it wants to use the control arm as leverage to keep it from spinning, the other side is a bit tricky, I found a small clamp fits nicely in the small dimple in the rod and wedges itself just enough against the control arm to keep the rod from spinning

[Gregski]

and a few moans and groans later...

Note: one lower control arm already had a little date with the wire wheel

[Gregski]

Good Enuff Garage:

Chevy C10 67-70 drum to 71-72 disc components

YouTube video

[Gregski]

I first wire wheel the grime, rust, and dirt off of all the parts and then treat them to a power washer bath

[Gregski]

then I media blasted them

[lolife99]

I like all the detailed info on your control arm rebuild.

Since I only deal with lowered truck,… I like to trim a portion of the “gutter” as I call them.
Just 1” to 1-1/2” on each side of the lower balljoint hole.
This allows for a 15” wheel with up to 4” backspacing to be used with a drop spindle.
Not needed for stock spindles.
I know some say it’s not necessary, but they make 2”, 2.5”, and 3” drop spindles for these trucks.
And even if you’re running a bigger wheel, you never know when you might have to throw on a spare.

I trim the gutters and clean them up with a flap disc.
Don’t leave any sharp corners.
I really like to do this ON the truck so you can rotate the wheel back and forth to check clearances.

Great thread.
I didn’t mean to interrupt it.

[Gregski]

Originally Posted by lolife99

Great thread.
I didn’t mean to interrupt it.

thanks, and please interrupt away, it is OUR thread and just a small extension to all the heavy lifting you have done for all of us already

would you be be able to provide me a template or some measurements where I should weld back my steering stop on the lower control arms, I have a separate thread for that, but it's related, I learned someone ripped them off my lower control arms, and it may be a good idea to weld something back on, I just want to get it in the right place

[lolife99]

Originally Posted by Gregski

thanks, and please interrupt away, it is OUR thread and just a small extension to all the heavy lifting you have done for all of us already

would you be be able to provide me a template or some measurements where I should weld back my steering stop on the lower control arms, I have a separate thread for that, but it's related, I learned someone ripped them off my lower control arms, and it may be a good idea to weld something back on, I just want to get it in the right place

I don’t really have any kind of template.
I never remove them entirely.
I cut off the taller “stand” that holds the rubber bump stop.
Then I just leave a portion of the steering stop for the spindle to contact.

[Gregski]

progress not perfection

[Gregski]

so I am getting a bit ahead of myself but I figure if I am going to document any of my research I might as well do it in public to share and help others, so here we go:

Fun Fact: You can drive yourself crazy shopping for ball joints for this conversion! How crazy is up to you, ha ha

case in point, in my imagination I was raised by a grandmother master mechanic who was a firm believer Made in the U.S.A. is better, she had Craftsman, MOOG, and ACDelco tattooed on the small of her back (I'll pause and let you recover from having to picture that) it would break her heart if we were to tell her MOOG is no longer solely made in the USA, but all over the darn world, and the quality varies accordingly!

so I start my research with MOOG upper control arm ball joints (don't wanna piss off grams)

• O'Reilly's: MOOG Part# K6124 (says it fits 1971) but costs $78 bucks

• AMAZON: MOOG Part# K6124 (says it does NOT fit 1971) but costs only $33 bucks

[Gregski]

so let's meet our new 1971-72 disc brake spindles

Left hand side is part # 3969461

Right hand side is part # 3969462

[Gregski]

I know what you is wondering: How much do these bad boys weigh?

[Gregski]

so I was over at my used 67-72 truck parts suppliers barn the other day and we was just standing there staring at both a 67-70 crossmember and a 71-72 crossmember and the only difference we could spot was the extra brake line brackets on the front of the 71-72 crossmember for the disc brakes, is that the only difference

Joe does drum to disc brake conversions by unbolting the 67-70 crossmember with all the drum brake control arms and spindles on it, and just mounts a 71-72 crossmember with all it's disc brake control arms and spindles in it's place and it just bolts right up

I told him about lolife's (Keith's) write up and how he could just swap out the ball joints and tie rod ends

[Gregski]

just stumbled on this OEM control arm bush listing on eBay and thought I would share

Part Number 3842882 GM NOS (New Old Stock)

[Gregski]

alright it's been a while since I posted so let's catch up, one of the things I discovered about my lower control arms is that the previous owner lopped off the steering bump stop, I don't think that's a good idea as now you are relying on the steering box to bottom out and stop the wheels from turning, so I had to go out and hunt down two new(er) ones

here I am removing a very stubborn shaft from the newer lower driver side control arm using a 2010 Honda Pilot in midnight blue metalic

[Gregski]

I'm loving my media blasting cabinet, it's a game changer

[Gregski]

so I went out and purchased the Clint Eastwood powder coating "system" aka powder shooting gun and plan on powder coating these bits, starting with the shafts, I will make this silver just to give it some contrast

[Gregski]

this is an old electric oven I kept from a Condo we sold years ago, it will do 450 MPH downhill so it's all good

[71meangreenc10]

Nice work.

Smitty

[Gregski]

Originally Posted by 71meangreenc10

Nice work.

Smitty

thank you, I appreciate that

[Gregski]

lower control arms (with steering stops) media blasted

took me a while to source these super thanks to those who helped me out, one of youz is a member on this forum you know who you is, thank you so much

[Gregski]

and into the Oven-A-Tor, note the quick release clamp ranked up to 71 fig newtons

[Gregski]

powder coated lower control arms

[Gregski]

upper control arms baked