it can restore your compression and therefore improve performance dramatically yes.... compression tests show that even after a few thousand miles.... some of the insides may not be shiny and new but when the truck has one foot in the grave this stuff can help sometimes its just silly to dump thousands into a beat truck that will only be worth hundreds only to have something else like the transmission fail a week later....
point it the stuff works in the right application when used right. its been tested..side effects or not the benefits usually out way them in those cases...if the trucks already got over 200,000miles obviously the owners are doing something right?
We are not talking about a 69 charger here guys... these trucks do have a lifespan and these products can end prolong the end of it period....would I use it on something new or with low miles? no....

 

It all depends upon how it fails. Normally, they just wear out slowly. Noises that indicate excessive wear creep in, oil control becomes a thing of the past, and finally something big happens that puts it on the shoulder. Every now and then, though, something big happens first. Ya rolls yer dice ya takes yer chances.

Ah, the raging controversy. I suggest switching over to a "high mileage" motor oil and otherwise just keeping up on regular periodic maintenance. You might also consider using an oil filter magnet to catch the microscopic bits that by now your engine is scrubbing away from various friction points. Just make sure that if someone else does your oil changes you point out to them that the magnet has to be moved over to the new filter and positioned properly, and then check before you leave that it's really on the filter properly.

If the maintenance has been done on schedule, you've not overheated the engine severely, and you've never let necessary repairs slide you can probably get 300,000 to 350,000 miles out of it. You might get closer to 500,000 if you've been and stay right on top of things. If you let things go, it could leave you on the side of the road tomorrow.

Don't go adding magical fix-it liquids to the thing unless/until you're sure that the next stop is the wrecking yard because you're not going to rebuild the engine. If instead you intend to rebuild the engine, don't use the magic fix-it liquids at all because it's practically impossible to get that crap out of the small spaces where it tends to hang up.

 

Now that I cant really argue with...

 

I thought my post saying, "It is used for when you are going to sell your vehicle" meant what UR said. If you plan on keeping your truck for longevity, then it is not smart. If you only want to get about another 3 years out of the vehicle...ok.

That is why you change all fluids RIGHT AFTER you buy a used vehicle. No telling if they added radiator, engine, or tranny stop leak type stuff.

I have been using lucas with my oil changes for the past 3 years (10 oil changes over 13K miles). I have seen no detriment from doing that, but you can argue that the frequency of my oil changes has more to do with the cleanliness of my engine than lucas. Plus I only use Mobil 1 or K&N oil filters. I tried a napa gold on my last oil change. Are napa golds a good filter? They seem pretty cheap to be that good.

 

its used when it no longer makes sense financially to tear the whole motor down for a little leak or your trying to stop your vehicle from burning so much oil and you dont antisipate actually having the engine rebuilt. I know the risolene stuff that is supposed to work like "restore" works I saw an increase in oil pressure and less oil burning... I added it 5 or 6 years ago with no ill effects... I have also used restore as well on my lincoln but sold the car a year later and it burned a lot of oil so it was hard to tell how well if at all it worked...
Have you ever used them or are you commenting from speculation and repeating what you have read from others who may not have any experience from it either? Or perhaps they used it wrong?

Whether it would or wouldnt, To use it with the thought in mind that it will trick a buyer and destroy the engine and screw the guy or gal your selling it to?.... Well to each his own but I dont do that **** to people...I'm not an a**hole. (not intentionally anyway) I've been on the wrong side of that fence.. (when I bought this truck and found the seller lied through his teeth to me) I like to think I'm better than that.

And let me also mention that most vehicles never get the engine rebuilt in their lifetime, So whether it does or doesnt leave residue in nooks and crannies where it doesnt effect performance is a moot point in most cases... so again...For the majority of old beat daily drivers this stuff has a purpose.

 

Is that comment directed at me?

 

No, I already said I see where your coming from. being cautious and skeptical of something is normal.

It more or less coming from the comments stating its all garbage and will destroy an engine from those who havent used it and have no basis themselves to make such firm statements about its effects.
"The whole dont knock it till you've tried it thing"
I have used both over years and had no issues arise from it.... only the added benefit of a dry garage floor or driveway and and in some cases less issues with fouled plugs and burning oil.
I will clarify to say the stop leak I used was for my radiator so I'm not sure how the engine oil stuff actually works but I was under the impression that it worked its way into cracks filling them and sometimes swelled gaskets and that you changed the oil shortly after like your supposed to with the restore and risolene stuff... I myself have been too skeptical about the oil stop leak to use the stuff but wont go as far as to bash it without having first or second hand experience from a trusted source.

Synthetics like mobil one have smaller molecules than conventional oils and therefore usually will find its way through smaller cracks than conventional oils will. this is one of the scientific reasons it can perform better than conventional oils in lubrication and also one or the reasons it can be a nightmare once you switch from oil to synthetic on a high mileage vehicle... High mileage oil is supposed to have additives that cause swelling of gaskets to prevent leaks (seal conditioners) as well as additives that improve compression and precent further compression loss and lastly other additves to prevent oil burnoff... basically it regular oil with additives already added.... further proof that additives can help right? just dont expect magic day and night results from a can.
(btw my ram uses castrol High mileage oil)
I gotta say I find it funny some people will ignore the FACTS and promote other unproven things like aluminum plenum plates being superior even though the bolt length was the only real issue for gasket failure and the aluminum ones are thicker which solves that issue in a very sneaky way while misleading the customer, yet so religiously call out other things they have no experience with as snakeoil...

 

I tried it on one vehicle, it didn't work. I didn't think I had to type my whole life story in a thread to make my point.

And you are still missing my point. If you want to keep the car for a LONG time, then don't use it. If you just want to get a few more good years, then use it. It just depends on how long you want the vehicle.

And about the seller thing. I never did that, but that is what you hear of people doing all the time before they sell their cars. Like sawdust in the engine.

I know that you like your theory that we are all talking out our asses with no experience, but that is wrong as most of the people here have experienced and have done the research.

However, you say "It works" without listing compression test numbers before and after. So it is hard to believe you.

 

oh, and BTW, instead of high mileage oil, you can use a quart of ATF in place of oil and it will help swell the gaskets and seals. The ATF that is best is the stuff that KILLS our trannies. Forgot which one that was. But the reason for killing our trannies is because it swells up the seals in the tranny too much.

 

Well, it seems I unwittingly set off a salvo of cannon fire! The product I used was Lucas, and I have used the Lucas steering stop leak as well. It works to stop the leaks, and so far hasn't ruined anything, but I can't say for sure if it is harmful or not. For the engine stop leak (it was a high mileage additive of honey consistency), I did change it out after a few hundred miles, and didn't add it back in. I've used those products in my import car with a turbo, and my boat steering system as well.

My original question came about because an expert on a 4 cylinder gasoline engine for boats - the 'Atomic 4 (widely used in the 60's and early 70's) - always recommended using Marvel Mystery Oil in the gas and oil of those old engines. Said it reduced the chance of a sticking valve and whatnot. Boat engines tend to sit around without use a lot, but my truck does sometimes for a couple of weeks. I was just wondering if anybody concurred with using an additive like an 'upper cylinder lubricant' to ward off problems.

Interesting that some of you expect the engine to go 275-300,000 miles! I hope so!