STP and Transmission: any negative experience ?

Terry said:
It MAY be ok, It MAY not be! Generally speaking, in 1930 (28, 29,) it was the place to have your timing lever. However, with the higher compression heads and oversized bores you may have to back off a few degrees or you get preignition and that will ruin your bearings . Have you done a compression test? Your head may be stock, or an aftermarket High Compression. Or just ground. Your cylinders may be as much as .125 oversize or 215 cu. in. as opposed to it's original 200.5 . This is an increase of 7% in horsepower, I don't know what it will increase the Comp. Ratio by. Does it have a large B or C cast into it? This would also indicate either a model B ( C ) or a police head ( B ). Both are higher compression than a stock A head. Normally, most people can hear pinging, I can't. If your engine pings, back the timing off till it stops while at speed on the highway. When climbing steep hills, back the timing off a few degrees. When running slow back it off a few degrees . Modern engines perform these operations automatically as did the later mod B 1932 - 1934. with a centrifical advance This timing stuff is controversial and it can be confusing and you will meet guys who tell you to set it and forget it. But the timing can be critical to engine life, gas mileage, and performance. For me, "set it and forget it" is not good enough.
Terry
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I through so many times about your comments. I think I read it in the drivers manual of the car. The manual explain what you wrote. The driver has to advance the timing with speed and retard in slops.

Then I searched the net and I found all kinds of answers.

As I live in Massachusetts, we are surrounded of slops, a lot. On my first trip to the downtown of my town, I was in the middle of a slop and I have to stop the car, and take it all the way in 2nd. Suddenly I realized I had the lever all retarded.

As this matter (how to use the advance and retard correct) worried me a lot I started to ask all around. At the end all were using it in one position "half or full advanced". The same I was reading on internet.

Bottom line, I followed what i was told at the clinic after the car was tested by experts.

I do not hear any knocking when going up in a slop. But for sure i feel the lost of speed and the effort of the engine.

About the car history:

I was told, and have the pictures of it, that around 2005 the car had an off-body restoration. Fully dismantled and motor was redone. I do not have more info. Only the pictures that proof the restoration. That owner had a bike accident and could not drive it more. Sold the car ~2015 to the person who sold the car to me.

The car is in excellent shape, mechanically and all the rest. No rusted sections at all. Both owners took care of it.

How much is still original in the engine ? I do not have idea.

That is all the info I have.

Cheers
Daniel
 
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katy said:
STP is not an oil, it's an additive.
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Katy

Isn't a car oil made of "mineral oil and petroleum distillates " ?

I am asking because I just don't know.

Google " STP MSDS" and will pop up a pdf file with this data on it :

60-100% mineral oil-petroleum distillates
< 5% Calcium long-chain Alkylphenate Sulfide

 
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You can probably compare the STP MSDS and any car oil MSDS and find they're nearly identical.

Yes, there are those who claim that STP is not a lubricant. And (surprisingly) there are those that claim that car oil is now an "engineered product" and that the old oil of the past is gone.

Truth is - the margins between almost any two products used for lubrication have diminished as engineering continues to "push the envelope."

And - as I said earlier about Cadillacs - nobody will find fault with their own decision - and may even run down or critique decisions made by others.

Not to characterize because I'm one of them - all 64 years of it - but consider who populates this board - all of differing backgrounds, experience, engineering acumen, or confidence levels but with a commonality which is not necessarily complementary - and some consider fault.

And take your informational pill with plenty of water - or scotch - to wash it down.

Joe K
 
Joe K said:
.....And take your informational pill with plenty of water - or scotch - to wash it down.

Joe K
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Joe, I love that end of your post. You are 100 % correct. I was expecting diversity in the answers. From those answers I learn and at the end I have to arrive to a conclusion of what I a m going to do.

For now after all the reading my conclusion is that I do not have enough evidence to feel comfortable using 100% STP.

I have 3 600W oils from Model A sellers. I will pick the one that I feel is more dense and add 10-20 % STP to help on that density.

I think that will work and is within STPs recommendation.

If anyone disagrees, please !!! Let me know the why. That's the only way to learn.

Thanks to all !!
Daniel
 
Opinions are interesting, but of no value without experience to back them up.

SAE 140 gear Oil works in the transmission and the differential! Here is my evidence.


Since I restored the transmission and the differential in my Coupe during the 1970s, it has accumulated 50,000+ miles with SAE 140 Gear Oil in it, and it has not worn-out or broken-down or become noisy. Shifting in hot and cold weather works well. This car cruises at 55 MPH and I have run it over 65 MPH many times with a stock 3.78 differential and no overdrive!
 
STP mixture is a trade secret as indicated on the MSDS. What is in there is no mystery it's just the amounts of petrolium and additives is. The stuff was formulated originally back when most of the engine oils available were straight grade like SAE20W20 and SAE 30 which were likely the most popular viscosities used at the time. What Studebaker came up with was an additive that would help an oil burner retain more oil for the short term. Engines with a lot of blow by have a lot of combustion heat getting into the crankcase and further thinning an already thin mixture due to all the excess heat in there. The additives were designed to help the lubricant stick to surfaces better to reduce the blow by a bit. Most folks with a mechanical knowledge of the internal combustion engine know that any "fix" for a worn out engine is temporary in nature. They still burn and leak plenty of oil in that state.

With modern multi viscous oils the 10 in SAE 10W30 is the oil viscosity with the polymers relaxed and in a cool state. The 30 in SAE 10W30 is the viscosity with the polymers fully expanded due to heat. When you add STP oil treatment, its kind of a mystery where the cold & hot viscosities end up during operation of the engine since it is less predictable on where the viscosity will change with the polymers involved. Most folks guess at where they will go. STP Corp will tell you that it increases by about a full SAE index number so in a perfect world that would be somewhere near SAE 20W40 but it's all just a guess. All viscosities break down with time and the pressure of operation so where does it end up after 200 or 2000 miles? We know the polymers also are pretty well spent after 3000 miles as well.

On gear lubes, it's even harder to predict since they are graded differently and with different ranges of viscosity than motor oils. The pressure on them is likely higher than in the engine. What is the viscosity of straight STP? What is it after 2000 or 3000 miles? What is the viscosity of SAE 140 GL1 after you add a pint of STP to a pint of SAE 140? You will quickly find that NO one can answer those questions or what happens after 2000 miles for that matter.

STP had to settle a suit back in 1978 for advertising claims that they couldn't substantiate and they aren't the only ones either. Quaker State was hit pretty hard on Slick 50 as well. Companies producing these products are very careful now not to tell the customer much about what the product actually does for them.

If the product works for you then keep on using it but be aware that there are alternatives. Ford dropped the use of 600W after the model A era when they started using partially synchronized transmissions and they never went back. They were using SAE 80 gear lube in the cooler climates and SAE 90 in the warmer climates. The gear oil mixed with soda soap for the U-joint was the only odd mix after that.
 
Forddan said:
Katy

Isn't a car oil made of "mineral oil and petroleum distillates " ?

I am asking because I just don't know.

Google " STP MSDS" and will pop up a pdf file with this data on it :

60-100% mineral oil-petroleum distillates
< 5% Calcium long-chain Alkylphenate Sulfide

You're correct, STP is a type of oil, but it's not sold as an oil it's sold as an additive.
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All lubricants that are natural mineral base are a product of fractional distillation process from crude oil in a heated column. Oils for lubricants will come from a paraffinic crude that contains hydrocarbon chains that are good for this purpose. There are other forms of crude oil but they aren't all conducive for the purpose of distilling out good quality lubricants.

It depends on what part of the fractionating column the liquid is siphoned from as to whether it will have the properties required for specific base stocks in the lubricant blending process. Additives for anti wear, anti corrosion, anti sludge, and anti foaming are all added in during a blending process and each company that sells one of these products has their own recipes but by nature of the use, they are pretty much the same product. In order to meet MIL-Specs, they have to be the same. I watched an episode of "How It's Made" where they were blending a batch of motor oil in a mixing vat. One of the employees came over with a bale of polymer plastic material and just dumped it in there. I was surprised that that is how the multi viscous oil was blended. After it was all mixed up, it all went to the bottling station for consumer packaging.

Heavy gear lubricants come off a lower part of the column. A GL1 grade of lube will have no EP additives and a lesser amount of overall additives blended in where a GL5 will have more with the EP additive blended in.
 
I watch "how it's made" too!You seem to know more than I do about oils and such. Maybe you can answer this. It's always bothered me. Back in the day around 1962 my friend and I barely managing to keep a 53 Ford with a flat head V8 running. This Thing was using oil! A trip 20 miles out and 20 miles back would use as much as 4-5 qts. We had no money for this and we got oil from anywhere we could just keep pressure in the engine. When we got the engine out we found about 60 (1/16) endplay in the crank. But we had a guy next door who donated about 10 gals of used 10 weight vacuum pump oil. We were very nervous about using such light oil. We would have preferred 90 wt gear oil. Finally, push came to shove and one day when the end was getting close, we poured the stuff in. A few miles down the road, we checked it. Yeah it was down a little but no where near what we thought it would be, 10 Wt? we thought the stuff would run through the engine like water through a screen. It actually cut the consumption a little better than half. Can you explain why the super light vacuum pump oil stayed in the engine while the normal motor oil poured out?
Terry
 
Vacuum pump oil is special stuff. It is distilled sometimes multiple times to lower its vapor pressure and reduce any moisture content. The lower vapor pressure is important when it is acting to help a rotary vane type pump seal between the normal outside air pressure and the low pressure of the vacuum being drawn. Being a highly refined material, I'm not surprised that it would last longer in an engine with a lot of blow by. I don't know how well it lubricates but I doubt it would hurt an internal combustion engine in the short term. The only problem is that the extra steps it goes through in the refining processes make it an expensive product for use in an engine. The low viscosity may also lower the oil pressure if there is a lot of clearance in the old worn bottom end bearings. It would likely have no additives to hold waist products in suspension either. In a vacuum pump, there is no worry about combustion byproducts.
 
Thanks Rotor, This sorta bothered myself and my friend, the why of what kept it in the engine when it was so light. As far as I can recall, it didn't seem to effect the power one way or another. Within a week we had the engine out of there and replaced with a "new" rebuilt from R & S.
Terry
 
On the STP web page under FAQ is the following:
Can I use STP® Oil Treatment in my manual transmission?

STP® Oil Treatment has been used successfully in manual transmissions, gearboxes and differentials at a 10% treat-rate by volume (i.e., 90% oil and 10% Oil Treatment by volume). Do not overfill.
 
Back in the 60's to 70's, Young kids filled ****** with STP, went down road


And it blew. I would mix 50-50 with oil.
 
DHZIEMAN said:
On the STP web page under FAQ is the following:
Can I use STP® Oil Treatment in my manual transmission?

STP® Oil Treatment has been used successfully in manual transmissions, gearboxes and differentials at a 10% treat-rate by volume (i.e., 90% oil and 10% Oil Treatment by volume). Do not overfill.
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Clever answer...rather than say "yes you can use it" they said it's "been used successfully"...that's not a yes.
 
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Jim/TX/GA said:
Lubriplate SPO 299 is ISO Grade 1000; they also classify it SAE Gear Oil 250 Heavy. That is quite thick. Probably too thick.

Lubriplate SPO 288, with ISO Grade 680, SAE Gear Oil 250, is closer to the original 600W. This may even be too thick for cold climates, until the transmission warms up. But if you know what's happening and adjust shifting appropriately, it's OK.

The Ford Service Bulletins mention diluting the 600W with 10% kerosene in the winter to thin it out a bit. I don't think I'd bother with that, but you can (if you are driving your A in Minnesota in the winter!). Or use the thinner Lubriplate SPO-277 (ISO 460) in winter, only in the transmission.

With an ISO Grade 680 oil in the transmission, the gears in the transmission will slow down their spinning very quickly when you step on the clutch and shift to neutral. It makes driving and shifting a pleasure. You do not need to double-clutch when going from 1st to 2nd and 2nd to 3rd gears. You only need to double-clutch when going from 3rd back down to 2nd gear at speeds above 15 MPH.

MANY Model A transmissions have been filled in the past with "modern" gear oil that is way too thin (like SAE 90 or SAE 140 oil). This was mostly done out of ignorance of what viscosity the original oil was, and the guys used what they had on hand. They did not have an SAE 250 oil (probably didn't even know it existed!). As soon as you do that, the shifting problems begin. You have to double-clutch on every shift because the gears spin too fast for too long, so they clash when you shift. Thus began the old wive's tale that you had to double-clutch a Model A all the time. Not so.

Answering the Original Poster's question, STP is not a stand-alone lubricant, it is a thickener additive. It is not intended (per the manufacturer) to be the only thing you put in a gearbox. They say add 10% STP to your manual transmission oil. Sure, running straight STP may work OK, but why do that when the proper ISO 680 (SAE 250) gear oil is available?

YMMV.
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Very good information here and you're spot on by asking why use STP when you can buy proper gear oil to suit the car.

I think you're probably correct that real 600w (not the fake stuff the suppliers sell) was thicker than SAE 140. Note that there was a SAE 190 standard for gear oil, and it's still available:

https://www.amsoil.com/lit/databulletins/g2498.pdf

(this Amsoil is good but expensive)

Penrite Transoil 250 is a better way to go than STP but I don't like that a full spec sheet doesn't exist (such as the spec sheet on the Amsoil 190 and 250 SAE in the link just above)...fair-dinkum oil makers provide full specs unless they're selling low quality stuff. We don't know the pour point for Penrite Transoil 250 but my guess is it's around freezing.

Lubriplate SPO 288 spec sheet is here:

https://www.lubriplate.com/Lubripla...Fs/PDS/Lubriplate/6_4_SPO_Series.pdf?ext=.pdf

Non-synthetic Lubriplate and Penrite are good, but the Amsoil synthetic clearly outperforms them.

For a few dollars more than Lubriplate SPO 288 and Penrite Transoil 250, but cheaper than Amsoil, you can buy high quality full synthetic ISO grade 680 gear oil that's yellow metal friendly and with a pour point of -30F. The problem is often these oils are only available in 5 gallon pale size or larger but I've found a couple of companies that sell it in gallon jugs for a fair price for the quality you get.

 
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Hi all

I wanted to update the thread letting you all know what I finally did.

After all your answers and my readings I decided to order a gear oil that I can buy in small quantities and could be as dense as STP. If you pour a bit of each one, they both looks very similar, concerning density. Definitely they are more dense than the 600W oils I have from 3 different Model A vendors.

https://www.restorationstuff.com/ecommerce/index.php?main_page=product_info&products_id=1088

LUBO26 (Meropa 1500) from Restoration Supply Company.

I did the oil change yesterday, but couldn't test it because it was raining. I will go out today for a short test. Tomorrow I have to drive 30 miles to a model A club picnic (60 miles round trip).

After the weekend I will let you know if I have seen any difference when shifting gears. Nevertheless, I have seen I am improving and most of the times I am able to shif with just a small grinding or without. Let see if this more dense oil helps me on my learning curve.

Cheers
Daniel
 
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I drove the A ~3 miles. As I am new, I am not sure if what happened was normal or not after a transmission oil change.

Started and warmed the car for a few minutes. Until the idle sounded good. Left the barn and when I tried to do 2nd gear it was too difficult. I tried double clutching or directly when the car just started to move. Very difficult. I live in a quiet street and drove along it, several times, stopping and starting again. Trying to understand if I screwed it. Then shifting started to go better and better with no grinding at all or very soft.

Question to the experts: I drained the transmission overnight and filled next morning with the Meropa 1500.

Could be It took time to this gear oil to oil all the gears ? (As if they were too dry)

Could be it was a combination of temperature (~21 C/70F) with the fact the oil was new and not yet well distributed?

Well, after I feel all was going back to normal I took it for a ride to the gas station under a soft midday local traffic. I tried not to think too much if the gears will grind or not. I focused my attention on the motor sound and time to shift. It went very well. Shift changed much better.

Let's see tomorrow during the long trip.

Cheers
Daniel
 
Highly doubt the gears were dry as the counter shaft is always spinning and slinging oil all over the inside of the transmission.


It sounds like a typical Model A to me, they can be very particular about rev matching. I think you'll find the more you drive the better it'll shift.



There have been a couple cases when I missed the 1-2 shift, tried to rev the engine to match the road speed and ended up having to stop and start over... this happened right after getting the car out for the season, had to re-learn how to shift.
 
Difficult to shift - grinding gears?


I had this issue, then had my carb gone through, and was amazed how low teh A would idle.


After the idle was down, found that shifting was a lot easier. With idle at 400- 500 rpm, upshifting at lower Rpms, off the gas and pushing clutch in, waiting a second before shifting into neutral, wait another 1- 2 seconds then softly shift into the gear, work great. Was amazed at how smoothly it shifted. Can't hurry the shifting.
 
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