STP in shocks

When I rebuilt my set of shocks, and did the relevant research, I ended up using a 50/50 mix of 80W-90 diff oil and STP. This I understood gave a viscosity similar to the original shock fluid.
 
Gold Digger said:
I don't use STP in anything. I had 5 trucks on the road back in the 70's and 80's and one of my drivers thought STP was "the stuff". Cost me one power divider and two front spindles and wheel bearings and probably an engine.
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I have to wonder just how much good equipment has been damaged by that stuff. Back in 1963/64 I knew a guy who had a car and he drove it without an air filter for a couple years. The engine was smoking bad and using lots of oil. He decided that if a little stp was good for engines then more would be better. He proceeded to drain the crankcase and refill with 5 quarts of stp. When he started the engine it almost exploded and stp was everywhere. Not a pretty sight. Valuable lesson for a 16 year old kid.

Chet
 
As info, shocks rebuilt by Robert Paul will have glycerine in them. If you need to add some, get it at the local drug store.
 
I've got a bottle of glycerin, and it's viscosity is very similar to the 600W oil sold for the ******, steering box and diff.

Did they always add some alcohol to thin it?
 
The problem with using glycerin is that it absorbs moisture, much like the common DOT 3 brake fluid does. I'd rather use oil in my shocks.
 
Since there are those that claim that STP or some other thick substance will work, then I guess my thinking is wrong. It would seem to me that with that viscosity, they would be so resistant to movement that the shafts and arms would be likely to fatigue and break, the mounting bolts would shear, etc. Then I remembered two things: having driven thousands of miles with fenderless A's, I've observed that there is normally very little suspension travel; and the rubber balls in dog bone links and the springs in tube links allow a little travel before the shock arm moves. To observe suspension travel in a Model A, google or youtube "Model A Speedster, Jim Huseby".
 
My oldest son was a mechanic on a Drag Racer Team; he told me they used STP in the engine, however he said the engine was set up loose, after two runs, the engine would be torn down and any worn parts replaced; he further said to not use STP in a street engine as the STP would end up in the bottom of the pan and it would be a waste of money; he said using STP in a Model a transmission or rear end would be OK as the STP is captive and the transmission gears and ring gear in the rear end would pick up and circulate the STP continually.
I have used straight STP in my A transmissions and 50 percent STP in the rear ends for many years and have never had any problems.
Just my opinion, yours may be different.

Ron
 
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