leaf spring liner
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
Quanta has the correct liners (www.quantaproducts.com), and just about any light gray paint works for the spring leaves. 
Race Director
Joined: Apr 2005
Posts: 11,277
Likes: 2,139
From: Bowling Green, Kentucky
I just finished doing this work on my 1967 small block car. At one time, Quanta Products sold the zinc coating the was applied to the underside of the spring leafs by the original spring manufacturer. This zinc coating is no longer available from them. After extensive research, I purchased KRYLON Sprayon #S00740 Zinc-rich Cold Galvanizing Compound as a replacement. It is approx 93 percent zinc in an epoxie binder. I have used this same material in the chemical plants for galvanizing repairs and it holds up very well. The color match is also very close. Long Island and others sell a typical gray paint for this purpose. I purchased a can from LICS to compare it with the S00740. The color match is close and the S00740 is a zinc coating (as original) versus a paint. You can go on-line and search for availability is you desire to purchase. I was able to get mine locally at a New Orleans Marine/Industrial Repair shop.
Regarding the liners. I ended up buying the last two GM NOS liners in the GM Parts system (or so I have been told) and used them along with some of my old GM original liners to redo my spring. I used the NOS liners for the two longest ones and then shortened some of the originals to make up a set. I had to buy one liner from a GM Dealer in Pennsylvania and the other came from a GM Dealer in western Louisiana.
In my quest for the best liners, I also purchased a set from Quanta Products and a set from DR REBUILD. Both came highly recommended, and both would probably work okay. But they were definitely different from original and were different from each other.
Original 1967 liners are 0.057 inch thick and made from graphite impregnated polyethylene or polyproplyene. The NOS or NORS later ones from GM which are also no longer available were made from similar material but are only 0.040 inch thick.
The Quanta liners appeared to be made from a very soft and wavey/pliable polyethylene and are 0.042 inch thick. I called their tech line and they stated that they have not recently changed material or suppliers of these liners. Many folks highly recommend these liners.
The DR REBUILD liners are 0.032 inch thick, and appear to be made from very similar material to the GM ones. They also are highly recommended by many folks.
I do not know about liners from Paragon or Long Island Corvette Supply or Bairs. You could call and inquire. I would find it hard to believe that there are more than two or three suppliers out there for these liners. But who knows??
You need to be aware, that installing thinner liners than original will very likely require that you machine down the two (of four) mounting bolts for the spring that thread into the blind holes in the differential. I know that I needed to machine off about 1/16 inch to keep from having these bolts bottom out inside the blind differential holes. This is due to my using a few of the thinner GM liners. So be certain to check your car before installing and tightening these bolts. Also, you DO NOT torque the four spring mounting bolts until you have the car back on the ground and the spring and suspension at normal orientation/height. Otherwise you can crack the rear differential cover. Many have learned this lesson the hard way. This caution is specifically called out in the GM AIM and the GM Service Manual.
Let me know if you need more or additional info.
SUMMARY: Some folks use paint and some use zinc rich compounds for the spring coating. Just about everyone has a preferred supplier for the liners. Most folks are happy. GM NOS liners are almost impossible to find. Good luck.
Larry
