STP in the primary
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Road Warrior
Joined: Sep 2007
Posts: 1,252
Likes: 141
STP in the primary
I had a buddy that used to put STP oil treatment in his primary. He never had issues that I know of but was wondering what would that do other than making it a little hard to shift cold. I don't know how much he put in but he swore by it. Has anyone done that?
randy
randy
Ultimate HDF Member
Joined: May 2008
Posts: 6,508
Likes: 168
From: WPB, FL
Huh?
STP is crap! It was the biggest load of horse **** ever introduced into the automotive aftermarket during the 60's! Did I sell it? Yes! Did I ever recommend it? No! The only purpose I ever recommend it for was to quiet down a failing engine if someone was trying to sell a car. What the heck Mario Andretti not being able to hold on to a screwdriver had to do with product integrity I'll never know!
Seasoned HDF Member
Joined: Jan 2011
Posts: 157,321
Likes: 56,881
From: Michigan 15 Minutes East Of Hell
Can't see how shifting would be a problem but the clutch sure wouldn't like it. I do remember being a kid and having a 66 Galaxie that had trans problems and we "gummed it up" with STP and it actually stopped slipping for about an hour ... then gave up the ghost
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Outstanding HDF Member
Joined: Dec 2008
Posts: 2,007
Likes: 353
From: Ohio
Nope, never done that. But you could put anything into your primary and swear by it. As to what it's supposed to do, or would do, is anybody's guess.
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Seasoned HDF Member
Joined: May 2012
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From: Carlsbad, CA
The basic premise of STP being very slippery seems contrary to what you want in the primary. It would seem to me it could cause clutch slipping, and less disengagement..
IMHO...a bad solution to a non existent problem.
IMHO...a bad solution to a non existent problem.
