STP as comfort food...

csandstecsandste Member Posts: 1,866
edited March 2014 in Geo
OK-- I admit it. I've occasionally used this stuff in old beaters and I think it's worked. My daughter ran her 1990 Prizm almost dry. I told her to keep the engine level up. She started putting in a quart of oil at every fill up without checking the dipstick.

Result--noisy engine with the oil pressure light coming on at idle.

The thing has 160K+ on it and unlike later model Toyotas apparently didn't sludge.

Anyway-- STP (or a no name variant thereof) quieted the engine and turned out the engine light on idle. Well worth the 79 cents I paid.

Any other positive stories about the joy of STP out there? I know lots of people who say that modern oils don't need this extra dollup of zinc and I think you're right if the engine's new. But what about squeezing a few miles out of that old beater?

I also cleaned up an old carburator by dumping in Marvel Mystery oil but that's another story.


  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaMember Posts: 64,482
    I think STP is basically harmless. The worst you can say about it with assurance is that whatever problem disappears by using it will come back shortly. So what you have with STP is (sometimes) a very temporary solution to what is probably a very permanent problem.

    But like you say, if it gives you peace of mind, or a week's relief from noise or smoke, for .79 cents that's a pretty good deal. You could buy a 55 gallon drum and a hand pump; however after repeated doses with STP I don't think I personally would want to be the poor guy who takes your engine apart.
  • fleetwoodsimcafleetwoodsimca Member Posts: 1,518
    Didn't Andy Granatelli start up the STP company? When I was a kid learning how to be a motorcycle gangster with my buddies (ha, ha!) we used STP in place of more expensive things like new rings and lower end jobs on our BSAs and Triumphs. It would work long enough to get us past a few weeks of sacking groceries, etc., and then being able to repair our bikes. Aaaaaaaaaaah, yes! Let us show some respect for good ole STP! We decided the name must surely stand for "Super Thick Petroleum."
  • zr2randozr2rando Member Posts: 391
    Yep, older engines, I'm for it, I have never believed that thin oil is for benefit of long engine life. I have caught a lot of grief on here because I use it, that's ok, we all have our own thing.
    I will also say it definitely has limits, Don't use TOO much, Don't use it with extended oil change intervals- it will NOT live as long as the oil will, If your engine has overheating tendencies you should probably swap a couple of quarts of 20w50 rather than use STP...
    In older engines that have served a major portion of their service life, STP(or the generic) can definitly quiet noise that is introduced by years of bearing/lifter wear, won't make the engine younger, but will give it some more time.
    Good morning y'all
  • leadfoot4leadfoot4 Member Posts: 593
    Just my $.02 worth, as I'll relate a story that one of my friends told me a long time ago......
    This friend was a fairly successful SCCA road racer with a 1963 "fuelie" Corvette. The team was freshening-up a new engine for the car, and the engine guy decides that STP should make a good lube when installing the piston/rod assemblies. He gives the cylinder walls a good coat of the stuff before sliding in the pistons.
    The folowing week, they take the car to the track for a practice day, and it's smoking like crazy. It runs pretty good, but it smokes badly. They load it up, take it home, and pull the engine apart for a look-see. Everything looked OK, and the only change to their procedure was the STP. The final conclusion was that the STP made the cylinder walls so slippery, the rings wouldn't seat in.
    They throughly cleaned everything, re-assembled the engine using the same parts, with only motor oil as the assembly lube, and it ran great. It seems that STP is at least some sort of friction modifier. I realize that this isn't really any scientific proof, but it happened to my friends, and they're pretty reliable guys.
  • dpwestlakedpwestlake Member Posts: 207
    STP is great if you're trading the car in and want it to stop tapping or smoking long enough to get a few more bucks on the allowance.
  • fleetwoodsimcafleetwoodsimca Member Posts: 1,518
    I have always considered STP to be a means of elevating the existing viscosity index, thus creating less blow-by and bearing chatter in worn to worn out engines. It works wonderfully well, and will likely always retain a good image with me. That which is loose will tighten up when you add STP!
  • isellhondasisellhondas Issaquah WashingtonMember Posts: 20,350
    But if the engine is already shot, I guess it won't hurt anything.

    Try working on an STP loaded up engine sometime!
  • zr2randozr2rando Member Posts: 391
    Sounds like some of you have worked with engines that someone tried a last valiant(desperate) attempt at getting that last mile out of a shot motor. I have seen engines that someone poured a quart of the stuff in and then tried to pass them off too. Years ago we always new that buying an older vehicle was going to be an STP experiment.
    If you use common sense and use it WITHIN ITS LIMITATIONS it will help older engines get plenty of extra life, it does NOT rebuild an engine, but used correctly it WILL get it some more time before it becomes a parts depot.
    I use it in my 1989 Nissan truck, I use that vehicle as a 3rd vehicle and don't plan on selling it anytime soon (I know it is worth more to me than the book says it is worth to anyone else). Motor is NOT shot, runs just fine, I just treat it like a motor with miles on it, not like it was 12 years (180k miles) ago. Stuff works good for me, but I know not to overwork it too,,I don't use too much and don't leave it in too long
    see ya
  • opera_house_wkopera_house_wk Member Posts: 326
    What a shock to see this heading today. I started it out with a story about how an outboard with a bad water pump would run twice as long before seizing when STP was added to the gas. Your buddy with STP on the walls was just trying to cover up for a bad engine job. Shouldn't have smoked that long. STP is a great assembly lube but I would never put it on the walls. Just as you wouldn't use grease there. I use it on engines that sit around for weeks between starting. It clings a lot longer. Now for more nostalgia.

    Way back in 1969 I was restoring an old wood boat. The engine took 11 quarts of oil and had no filter. I went down to the TWO GUY'S department store automotive section and bought Remanufactured Motor Oil in gallon cans. Sure wish I had those cans today! This was supposed to be old oil from fleets that was re cracked. It looked great. At that time I remember that it was common for most oil cans to include the term VIRGIN on the labels. So what happens to all that oil which is collected today. I know some uses oil is burned by shops for bay heat and some facilities have boilers that will accept it with other fuels, but thats a lot of oil. Is some of it mixed with new crude? After cracking, it doesn't matter what it first was and should be treated as any other material you recycle. Is that why virgin isn't on the label any more?
  • isellhondasisellhondas Issaquah WashingtonMember Posts: 20,350
    When I was a kid in the mid-late sixties, there was a place in Long Beach, CA that sold what they called reclaimed motor oil. If you brought your own container it was something like ten cents a quart. I think all they did was strain old motor oil through a series of filters.

    Talk about a filthy place!
  • fleetwoodsimcafleetwoodsimca Member Posts: 1,518
    In the past I saw STP motor oil for sale. Is it still around somewhere? I suspect it was just a packaging exercise, anyway.
  • opera_house_wkopera_house_wk Member Posts: 326
    and just saw a can of it yesterday in a flea market. I should have bought it for $2. Never could see how it could get through an oil filter. You had to shake the cans before pouring, else it would clump to the bottom. Great oil, bad marketing. People just didn't like putting something in their car that was darker than they were used to draining out.
  • al_saadallahal_saadallah Member Posts: 23
    The Smoke treatment of the Oil treatment?
  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaMember Posts: 64,482
    You're not supposed to coat the RINGS with the STP when rebuilding the engine, just the bearings for the crank and cam. No wonder the guy's engine smoked. He should have known better!

    I could see STP gas treatment working in a 2-cycle engine like an outboard because that stuff is not a gooey mess--it is actually, like Marvel Mystery Oil, merely a very light, hi detergent upper cylinder lubricant. Two-strokes of course depend on gas/oil mix for lubrication, so a bit more oil in the gas might help (to a point).

    But in the long run, if there is no substitute for cubic inches, there is also no substitute for re-machining work cylinder walls and fried piston rings and old engine bearings. These parts must withstand TREMENDOUS forces and I really don't see how something in a can is going to make much of a difference with such violent forces going on inside an engine.
  • fleetwoodsimcafleetwoodsimca Member Posts: 1,518
    I would be afraid to not use a recommended assembly lube in an engine after a complete tear down. STP for assembly would literally scare me! I have heard stories about cam lobes frying due to inadequate assembly lube.
  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaMember Posts: 64,482
    I have used it, mixed with oil and with a pre-coat of white grease. Never had a problem, but really I think the grease would have been enough. As for upper cylinders, usually priming the oil pump and cranking a little with the ignition disabled seemed to be cautious enough.
  • alcanalcan Member Posts: 2,550
    For faster pump prime, pack the cavities with petroleum jelly. If engine design permits, use a 3/8 drill to spin the pump up before initial startup. I use our Hastings bearing leakage checker to pressurize the system first through the oil sender fitting after liberally dousing the cam lobes and lifters/followers with camshaft break in lube.
  • fleetwoodsimcafleetwoodsimca Member Posts: 1,518
    In an emergent situation years ago I sat on the fender of my 1955 Chevy and ridge reamed all 8 using a half inch ratchet. Then I honed the cylinders using an electric drill. I changed the big end babbits and installed wide-land rings, and tightened down the heads after lubing the renewed areas with motor oil-- and I got away with it! But only for 20K miles. The STP came in after some break in.(:oÞ
  • Mr_ShiftrightMr_Shiftright Sonoma, CaliforniaMember Posts: 64,482
    And now we know the difference between a Chevy V8 and a Ferrari engine. You wouldn't get 10 miles doing that to some blocks, but it is amazing how forgiving American V8s are.
  • vwracervwracer Member Posts: 90

    I've heard that most used motor oil is used to make asphalt for roads.

    When re building an engine, I mix white assembly lube with STP and thin it with motor oil to get a very light goop that is just barely too thick to pour. I use a cheap pipe dope brush and put this mix on every moving part inside the motor. When time to start motor I fill with the cheapest non-detergent no brand $.69 a quart oil. I then start and run engine for 5-6 minutes and then drain the oil.
  • opera_house_wkopera_house_wk Member Posts: 326
    Interesting. Well, they would still have to crack it to make asphalt so while they were at it they could make anything else. I still think some makes its way back into some kind of oil. Should ask bobtheoilguy. No one would ever admit to it. There used to be a lot of small independent refineries that could have done that. Those days are gone.
  • fleetwoodsimcafleetwoodsimca Member Posts: 1,518
    I recall stories years ago about mixing STP and sawdust, and pouring it into badly worn automatic transmissions and differentials. This would improve the performance remarkably, and for long enough to get your vehicle sold to an unwary buyer, or traded in to a dealer. The stories never included chapters on what happened to guys that got caught doing that! (:oÞ
  • brorjacebrorjace Member Posts: 588
    STP has its place and according to the responses above, most people are using it correctly.

    But what bugs me is that it has always been marketed as "The Racer's Edge" implying it is for high-performance engines, even new ones.

    Well, I tried some in a single-cylinder, air-cooled engine and that thing broke that STP down into a watery waste in no time. Definitely a case of misapplication! All this stuff is a polymer-based thickener (unstable) with some useful additives so it is NOT for high heat, high RPM usage.

    --- Bror Jace
  • fleetwoodsimcafleetwoodsimca Member Posts: 1,518
    Yep! It can improve the perceived torque delivery from an under square single or twin air cooled engine that is somewhat worn in the rings/cylinder(s).
  • brorjacebrorjace Member Posts: 588
    Well, my palate doesn't appreciate STP as comfort food ... but what about Lucas Oil Stabilizer?

    Does anyone know what's in this stuff? Is it just like STP ... but under a different name?

    I see it advertised a lot recently and was wondering about it.

    --- Bror Jace
  • zr2randozr2rando Member Posts: 391
    Another good use for Google huh?
    When I buy Chainsaw bar oil, it says it has a tack additive in it to stay on the chain better, sounds like what this stuff is. It does not sound the same as STP because they seem to avoid the words polymer and zinc ...
    Only thing I saw that sounded fishy was they recommend anywhere from 20-60% mix and that sounds like the old "elixer" that fixes everything, of course alcohol usually does fix everything doesn't it? You know I use the STP stuff, but I am also aware of its restrictions, the LUCAS stuff sounds like it is more "stabil" ....only thing it probably thickens the oil at ALL temps, the STP stuff mainly changes 10w30 into 10w40 or 10w50 maybe, it sounds like the LUCAS changes the 10w30 into 20w-50 maybe.....maybe it would be the same as just "enhancing" the 10w30 by swapping out 2 qts for 20w50 instead???
    If you buy a bottle try comparing 2 jars with oil with and without it and see how fast it runs down the sides????, let us know ...
    see ya
  • brorjacebrorjace Member Posts: 588
    I was in an Autozone ... or Parts America and I saw guy buying a bottle of this stuff.

    I wish I had looked at the bottle, shaken it, etc ... at the time ... but I didn't. The image of that other dude plunkin' down some money for that gear-oil bottle stayed with me since, though. I don't even know what that quart costs. <:^(

    My guess is it's got a little of everything in it. Basically, more EP additives, anti-fuel dilution (& anti-corrosion) additives to bump-up the TBN, etc ...

    That sort of thing. Kind of like a bottle of "super-oil" ... enough additives to rejuvenate/reinforce about 5qts of "standard" oil.

    --- <b>Bror Jace
  • zr2randozr2rando Member Posts: 391
    ...that "sticky stuff" that it adds....You gonna go back and get sum?
    Hey it is Saturday night!!
  • brorjacebrorjace Member Posts: 588
    Rando, I went to their site and looked around. Here is a link to the stabilizer page and product info:

    Um, this stuff says it is 100% petroleum oil with lots of additives, probably ZDDP and possibly moly. Since they say it can stop oil burning, smoking, engine knocking, etc ... I'm guessing it is really thick stuff, perhaps straight 30-40 weight? When you mix this with typical 10W30 or 10W40, it makes that stuff a bit thicker ... perhaps like a 15W50 or so.

    Sounds like much ado about nothing, though. And, if they charge more than $3 per quart, it's highway robbery.

    If you use a good quality oil with the correct weight for your application, you don't need this stuff.

    But then again, that's the advice for nearly ALL oil additives. >;^)

    --- Bror Jace

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