STP/gear lub

I added some Morays which is similar to STP to my 1934 Ford trans and it had the exact opposite effect than I had hoped for. The slick gear shift I had hoped for was almost impossible to change when cold and very slow when hot. Don't waste your money and time. Regards, Kevin.
 
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Hey Harvs
My dad has been adding STP to transmissions for 30 years with absolute fabulous results, shifts smoother, quieter and less grinding if any!! As a matter of fact the last V8 he bought the first thing he did when he got it was loosen the shiffter and pour some in. From Model A to WWII Jeeps
 
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Fair question to kick things off. Then, two quick, equally convincing perspectives that are distinctly opposite. This is better than a political debate!
 
I would imagine that the differences are due to the condition of the respective transmissions. If used in a transmission with a fair amount of wear, it is possible that it might help a little, while with a freshly rebuilt transmission or one in otherwise good shape, it might be detrimental. When I was in college with no money, I used it a lot in my "beaters" and it literally kept them running. The last thing I would do is use it in a new car.
 
I would imagine that the differences are due to the condition of the respective transmissions. If used in a transmission with a fair amount of wear, it is possible that it might help a little, while with a freshly rebuilt transmission or one in otherwise good shape, it might be detrimental. When I was in college with no money, I used it a lot in my "beaters" and it literally kept them running. The last thing I would do is use it in a new car.
Nope, used it in a freshly rebuild Model A transmission. PERHAPS......the first post tried using it exclusively without the "proper" transmission oil??? MAYBE when used in "conjunction" with and as a 1/4 amount supplement to the transmission oil then its a "different" out come? Just an thought!!! OR maybe the product he used "isn't" as much like STP as he originally thought???
 
STP is not a lubricant. It thickens oil but dilutes real lubricants. Can't understand why I keep seeing posts about snake oil!
 
I had been ASE certified back in the 1970's. One thing that was taught and stressed when attending school was to NEVER use STP.
Why? Well, you only had to open up an engine back then that an owner had faithfully added that crap.
Yes, it helped quiet down a very tired engine. But what it really did was hold all of the contaminants in motion.
I can no longer recall how many engines I'd rebuilt that had been previously destroyed by STP. So many that when I opened one up I knew instantly what had been used as a so called lubricant.

Now there may be a place for this stuff. Just not anywhere near anything I own of value. I suppose it would coat the chains on my manure spreader nicely enough.
 
Lots of anecdotal stories, but no scientific facts......yet......maybe a chemist who knows about lubrication will chime in to clear this up.


BTW......I used STP in a Ford 312 engine for over 200K miles......the body rusted away and it ran like a clock when I sold it to a guy who put it in a fishing boat (not for the anchor!!).


I pulled the rocker covers frequently and never found any sludge.
 
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Lots of anecdotal stories, but no scientific facts......yet......maybe a chemist who knows about lubrication will chime in to clear this up.


BTW......I used STP in a Ford 312 engine for over 200K miles......the body rusted away and it ran like a clock when I sold it to a guy who put it in a fishing boat (not for the anchor!!).


I pulled the rocker covers frequently and never found any sludge.

How about a chemical engineer that used to schedule production at a lube refinery? STP is not a lubricant. A lubricant is a branching chain paraffin. Enough said. IMHO what saves most of us from foolishly adding STP to engines is we don't drive them enough to cause severe damage by diluting the real lubricant.

"STP Oil Treatment product claims include protection against engine wear (hence, reduction of friction) and reduction of oil consumption. There are no controlled test results or relevant customer testimonials on the STP web site to document these product claims.

In 1978 STP Corporation and its then-parent company, First Brand Corporation, settled a legal action from the FTC over misrepresenting the role and benefits of motor oil additives in reducing wear inside engines. STP paid an $888,000 judgment, the third largest sum ever obtained by the FTC for a consumer protection violation."

https://cdn2.hubspot.net/hub/68152/...bell_performance_xtra_lube_four_ball_0709.pdf
 
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in my model A i used 600 wt ,which is what it calls for ,it’s available at snyder’s or brattens antiques ,also in my 50 cpe ,i use lucas engine oil supplement in the overdrive trans and diff 22 years no problem ,but i don’t drive them in the cold ,and i don’t use the lucas straight ,mix it 50/50 with 90 gear oil
 
in my model A i used 600 wt ,which is what it calls for ,it’s available at snyder’s or brattens antiques ,also in my 50 cpe ,i use lucas engine oil supplement in the overdrive trans and diff 22 years no problem ,but i don’t drive them in the cold ,and i don’t use the lucas straight ,mix it 50/50 with 90 gear oil

Might want to do some research on what the so called 600 or 600 wt lube is! It's normally SAE 140 gear lube (which is what Ford called for) repackaged. 600W was a brand name Mobil used for a steam engine oil. Mac's claims there "600w" lube has a viscosity index of 2270, which places it in the middle of SAE 140.
 

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Use John Deere Corn Head grease. I had STP in my 32 box two years ago, did not like it and it leaked out very slowly.


Glenn

Interesting. I have my '32 box filled with straight STP right now. Maybe I'll drain it out and add Corn Head instead.
 
When I was 16, I had a job changing oil in big trucks. The boss told me to put 1 QUART of STP in when I refilled the oil. We kept the 5 gallon can of STP sitting on top of a big heater... so it would pour. I had a 53 Chevy and one day I changed the oil....not knowing, I put a quart of STP in it also. I was really cold in the shop (except by the heater). When I got ready to go home, the Chevy 6 wouldn't even turn over...had to crawl under and pull the drain plug.....slow oil. The next morning, the STP still hadn't drained out completely. My first and last STP in a motor. But they gave t shirts and decals at the races back then.
 
Interesting. I have my '32 box filled with straight STP right now. Maybe I'll drain it out and add Corn Head instead.

Whether STP or other products of that type (Power Punch, Bardahl) qualify as lubricants or not, the fact remains that the straight stuff in a manual steering box greatly reduces steering effort.
 
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