SUSPENSION

27 March 2004

I'll be using the stock front axle with a Classic Performance Products six lug disk brake conversion. It will use a dual master cylinder with power booster that mounts in the stock position and uses the stock pedal.

Click a picture to enlarge.

    I used a wire wheel to remove 50 years of rust and scale from the axle.

It cleaned up pretty good with just the wire wheel.    

It cleaned up even better with ZeroRust PrepStep but I forgot to take a picture.

2 May 2004

    After cleaning, the parts were painted with Rustoleum rusty metal primer then gloss black.

The springs were re-arched by Fort Worth Champion Spring.    
They got the Rustoleum treatment too.

25 May 2004

Here the front springs are installed.    

    One of my spring mounts was hurtin'.

I got a used part from Mothertrucker's Trucks in Arizona and now it's better than new.    
It is mounted with grade 8 bolts.

    I screwed up a spindle trying to get the old bushings out.
I made a bushing tool to prevent damage on installation. It's a piece of TV antenna pole.

18 June 2004

The front axle has been installed and now I'm working on the disc brake assembly. Picture instructions on installing the disc to your old hubs are on CPP's web site.

I made the mistake of applying ZeroRust and paint to my hub before trying to install the disc. Don't! I had to clean it all off to get the disc to mate properly. It is a tight fit. Any un-even thickness of the paint will make for a wobbly disc.

    Here's the disc assembled to the hub.

I ran into a couple of problems installing the discs to the spindle.

    Problem 1: The bracket hit the steering stop. I filed the stop down so the bracket would clear.

Problem 2: The bracket hit the king pin retainer nut. The instructions say you may have to grind the threads even with the nut. I filed the threads flush then filed off part of the nut. I ended up notching the bracket before I got it to clear.

       

Also note there is a bend in the mounting brackets. The instructions don't say which way the bend goes and their drawing isn't clear. The picture at "problem 1" shows the bend going outboard. That is wrong. The bend goes inboard as in the first picture of "problem 2".

   

28 June 2004

Now comes time to mount the master cylinder. More problems. Nobody said building a truck is easy.

The legs of the mounting bracket are parallel, the frame and the mounting surface are not.    

    After tweaking the legs to meet the frame, there was still a 1/4" gap between this arm
and the mounting surface. I cut it off and welded it to fit.

Underneath, the crossbrace fouled a crossmember rivet.    

    I tweaked the existing bend (blue arrow) and added a couple of extra bends (red arrows) and she fits.

Now it bolts up like it should. Note where bracket was tweaked.    

I tried stock 15" wheels and they would not fit. Stock 16" wheels will fit with just a little metal removal near the riveted bracket.    

This kit is marketed for 1947-54 Chevrolet trucks. I don't know if the GMC frame is different or if the bracket was just built wrong. I called CPP for advice and was told their tech reps don't work on Monday but he'd try to have one call me back within the hour. Nobody ever called back.

I'd still recommend the kit. You have to expect some modifications when you are modifying your old truck. I bought the master cylinder kit, the disc kit and the roller bearing kit. Everything I needed to make the conversion was there, no trips to the hardware store.

As you can see, I'm still months away from trying them on the road. When I get there I'll let you know how they work.

Charlie