1970 K20 Z62 Full Restoration

[IronCanine]

Originally Posted by cericd

Glad to have caught this one from the start. I'll be enjoying every step and taking notes.

I love getting the band back together.

[IronCanine]

The goal of this build is to produce the closest thing to a factory result as we can. That means NOS where I can. Date code correct where I can. Factory markings were appropriate for a late 1970 Fremont truck. It won't be perfect and I'll take some license...but I'll try and point it out when I do. Let's start with axles.

HO52s are tough for parts and getting tougher. But I was able to manage.

I expected my truck to be a 4.56 (which I think was the standard gear for 70 K20s), but it was 4.10s and dated right for the build. I got lucky (one of many Pete tips) and jumped on a rebuilt locker that Mike Cofield had on the board (hence SPID change #2).

Here's a good axle thread: http://67-72chevytrucks.com/vboard/s...d.php?t=200268

I used Raybestos 2009R drums.

[IronCanine]

Here's a tip...NP205 output shaft fits the rear hub bearing perfectly. Like GM made it to press that guy in.

Mine is a 70 so it has 1/2" wheel studs...and for whatever reason I had to go with slightly longer than stock on the rear. This is documented on other HO52 specific threads. The big challenge for me was my press wasn't big enough and my wheel stud puller/bearing tool wasn't up to the challenge. I had to have my wheel studs pressed in at a tire shop. You cannot talk them into carrying about your parts as much as you do.

[IronCanine]

Here's a pic of the brake set up just to prove I did it because it's a PITA. The only parking brake gasket that I'm aware of that you can buy is from LMC. See it next to OE piece on the leaf spring. It obviously doesn't match. I got some material from McMaster-Carr and made my own.

I believe this axle got painted as a unit from the factory with the stud threads masked (not the ends). Like most things on this truck, my primary reference is JoesJunk's 1971 10k mile K20. That truck is a time capsule and just happens to be a Fremont K20 built a few months after mine. And Joe was gracious enough to let me come and photograph that truck so that we've got the best chance of getting this truck right (or as right as possible).