REAR END

13 April 2004

The rear end housing is from a '55 first series Chevrolet. The differential is from a '59 Chevy 1/2 ton. Chevrolets make great parts trucks.

Click a picture to enlarge.

    Here I've started removing rust and scale from the housing.

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 September 2004

I bought new bearings for the differential then discovered the ring gear had been ruined by rainwater sitting in the housing for years. I found a new ring and pinion with the same ratio, 3:90-1. I had never rebuilt a differential before and when I read the procdure in the 1958 Chevrolet Truck Shop Manual it sounded pretty scary. So I said "I can do that." It turned out to be quite a project.

   
I had to build a couple of tools for the job. The one on the left is for the bearing adjusting nuts and the other is to hold the pinion yoke.

I don't have the tool for measuring the pinion for a shim so I had to go by trial and error. It took several tries. Each time it has to be fully assembled and the contact pattern checked. Then when it is wrong, tear it all back down again and change shims. This involves pressing the pinion bearing off and back on each time.

   
Someone suggested grinding out the center of the old bearing and using it to find the shim size. I ground out the old one and used it to press the new one on each time.

   
I don't have the rig to mount my dial indicator to the carrier either. I found I could do it by hand. It's not as accurate as a mechanical mount but by rocking it back and forth I could tell if I was in the range, .003-.010".

   
The '58 manual says to use red lead to check the contact patern. At NAPA I found the modern equivilent, Prussian Blue. I found some really helpful info on interpreting and correcting contact patterns at www.drivetrain.com

16 October 2004

   
Finally I got it right and got it installed.

   
New shoes, cylinders, springs, adjusters and parking brake cables

   
I moved the brake lines to the left side using the hose bracket from the '59 parts truck.