Adding STP

[barkleydave]

An old school Model A and T guy said he puts STP in his steering box and adds some to the tranny. Says it slows the gears down a little more and smooth's downshifting?

Has anyone used STP for this purpose?

[Joe K]

I have run straight STP in the transmission.

It seems to work fine. A little more consistent between cold and hot temperature.

Joe K

[barkleydave]

Thanks.... I tried a search first and then googled it and it found the earlier posts. See the topic has been well discussed!

Funny the more I think I know... the less I really do!

[Ron in Quincy]

I have run straight STP in my transmissions for over 30 years, allso 50 percent STP in differential and 50 percent 140 gear oil.
My oldest son was a head mechanic on a dragster team. He told me that the gears keep picking up the STP where it is captive and moving it to the top. He said not to use it in your engine as it is so heavy it will all end up in the bottom of the pan and could possible plug up the oil pump.

Ron

[billwill]

It will stay in the valve chamber or top end of the engine.Good Luck

[steve s]

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Just remember, you can't add any additive without simultaneously displacing a roughly comparable amount of the designated lubricant.

[Bob Bidonde]

Ditto Steve S!

[Jim Brierley]

I wouldn't use it, it's an additive not a lubricant.

[Pete]

Originally Posted by barkleydave

An old school Model A and T guy said he puts STP in his steering box and adds some to the tranny. Says it slows the gears down a little more and smooth's downshifting?

Has anyone used STP for this purpose?

Here is something I posted on here about 2 years ago.

Originally Posted by xmarine
Has anyone used cornhead grease in their 2 tooth steering box?Is it an adequate lube for this use?
No, I have not used it.
No, it is not an adequate lube for that.

Here is something I posted on the HAMB some time ago pertaining to steering boxes of the type found in most old cars.

"Put any kind of lube in it that you want and check the steering effort by pulling radially on the steering wheel with a spring scale. (front end off the ground)
Then drain it and refill with straight PowerPunch or STP.
Then check the steering effort. You will think you have power steering."

And no, I don't know why STP says not to use it straight when it works so well that way. Maybe it's because it is advertised as an ADDITIVE only.
Powerpunch doesn't say anything about that.

I found something interesting years ago in that there were quite a few
truck fleets that used straight Powerpunch in their steering boxes. This was long before they had power steering.

And no, I don't have stock in Powerpunch.

An interesting side note as long as you have the spring scale hooked up and the front end off the ground.
Drain the box and refill it with straight carbontetrachloride (CCL4). Try the test.
You will think the laws of friction physics have been repealed.
DO NOT try to run this stuff though. It will evaporate before you can get out of the garage.

[MikeK]

Originally Posted by Jim Brierley

I wouldn't use it, it's an additive not a lubricant.

This "Not a Lubricant" thing keeps popping up, taken out of context from an old Andy Granatelli advertising statement designed to give the impression you were getting something other than just another kind of oil.

The STP MSDS LINK shows the majority content to be a mineral oil base with something less than 5% added ZDDP. The mineral oil is listed as "mixture" so that would include viscosity modifiers and tackifiers.

Has the 60+% base oil content of STP actually been so adulterated that it is no longer a functional lubricant, or have the lawyers carefully absolved the company of liability by insisting it be mixed with some other 'lubricant' so that failure liability falls upon the other "lubricant", not upon STP?

[Flathead]

You make some good points. Nothing is simple any more.

[CarlG]

Story from my college days (early 60's):
53 Merc, 3-Speed + OD This engine was a real oil user. Whether it was just leaking it somewhere or burning it, I can't remember. I was going to college in Phoenix, parents lived in Las Cruces NM, about 400 miles. When I left Phoenix the oil was at the full mark. 100 miles, it was down 2+ quarts. Added 2 quarts oil, 1 can STP. 200 miles, it was down 1+ quarts. Added 1 quart oil, 1 can STP. 300 miles it was down ½ qt. Added 1 can STP. Arrive at destination, down about ¼ qt. So then on the return trip, I added another can of STP before starting the trip. Did not have to add any more on the 400 mile return trip. Still showed plenty of oil pressure, and was still at the full mark when I got back to school.

I don't know about it not being a lubricant, but it worked for me at that time.

[The Master Cylinder]

Originally Posted by MikeK

Has the 60+% base oil content of STP actually been so adulterated that it is no longer a functional lubricant, or have the lawyers carefully absolved the company of liability by insisting it be mixed with some other 'lubricant' so that failure liability falls upon the other "lubricant", not upon STP?

Maybe after loosing a couple of high dollar lawsuits, ~$888,000 to the Federal Trade Commission for false advertising for one, they figured out a way to protect their a$$.

[Slotblog]

My guy at Bert's recommended STP as steering box fill. Says it'll leak less...

[MikeK]

Originally Posted by The Master Cylinder

Maybe after loosing a couple of high dollar lawsuits, ~$888,000 to the Federal Trade Commission for false advertising for one, they figured out a way to protect their a$$.

That lawsuit was in 1995 and referred back to a 1976 FTC ruling concerning advertising claims. From a summary- "According to the FTC filing detailing the charges . . ., the defendants falsely represented that (standard)motor oil does not adequately protect most engines from wear at start-up; and that STP Engine Treatment with XEP2 is required to protect against wear at start-up in most engines."

The $888K settlement was basically for advertizing 'puffing', fairly common to most advertising. There was no FTC claim that STP products were harmful or ineffective in any way. Strictly a violation of FTC 1976 advertizing regulations.

[rocket1]

I used STP in my engine for years,I had occasion to drop the pan and found the STP was congealed in the bottom,glad it didn't get into the oil pump.

[Mike V. Florida]

Many use it, many don't, no reports of any harm from the model A masses.

[Joe K]

And one should be quick to note that there is a difference between using STP by itself as lubricant - and using it as an additive.

I've never used it as additive. It seems that at least one person has used it to satisfaction.

Slick50 another one - the guy at the County Fair who shows a Briggs & Stratton engine cut open and running (i.e NO LUBRICANT) to allow one to see directly the molecular advantage of Slick50 comes to mind.

Some thing do work. Others not so much.

Joe K

[SeaSlugs]

Originally Posted by barkleydave

An old school Model A and T guy said he puts STP in his steering box and adds some to the tranny. Says it slows the gears down a little more and smooth's downshifting?

Has anyone used STP for this purpose?

Ive seen and heard of this recently, id say go for it. if youve ever used it before it is stringy stuff that sticks to everything!

[John Stone]

When I take an engine apart, I can tell if the owner used STP. It is slick all over the parts that oil get to. A little solvent cuts it right out. That being said, when we let a car set for a while, the oil does drain down. Why not keep something slick on it for that initial start-up. Can't hurt anything and yes, it is an oil thickener which makes the engine run quieter. Just my opinion.