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Engine Oil Additives. Any Use?

13K views 42 replies 11 participants last post by  rodmaker 
#1 · (Edited)
I used to buy new cars. Not sure why - image? status? Keeping up with the jones's?
However as I have got older common sense seems to have clicked in and I realised this was costing me a lot of money with the value of the car depreciating dramaticaly as it was driven away from the dealer. Resale values were a nonsense compared with the purchase price.

So now I buy used. Some near new some not so new and with fairly high mileage. High mileage in a car has never really bothered me. My thinking on this is, "If it has done that mileage it must be pretty reliable." Backed up wth a reasonable service history. I was happy.

Anyway to the point:

I have couple of higher mileage cars that I like and want to keep and have been looking at additives.

I have often as I am sure most of you have, seen all the miracle claims for various oil additive. I have never bought these and always felt they were just a way of getting you to part with your cash.

What's your take on this fellow forum members?

Anyone got any positive or negative experience of engine/gearbox/power steering additives in their Renault?
 
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#2 ·
I've used Slick50 in my last 2 Espaces both petrol, and my Clio also petrol.

I thought they all have been more free reving, lower fuel consumption and smoother/quieter, all were 30K'ish mileage and out of warranty when treated and I think they only were retreated after an additional 50K, for all it cost I was pleased. Clio has not been retreated as its milage is still fairly low.

What did it do to the engines ... ? but nothing detrimental as far as I could tell, as none have had any engine problems , the gearboxes were also treated with the Slick50 gear treatment.


hope it helps :)
 
#3 ·
Hi Re the slick 50 there may be something in it.
I have a friend who told me about a friend of his who did the slick 50 treatment on a bench test engine in a school he worked at as a tech teacher. He ran an electronic tachometer on it to check the revs before and after treatment. The engine revs increased with the slick 50 at tick over. Indicating - as nothing else had been touched that friction on all the moving parts had decreased.

Was the higher MPGs significant?

Food for thought.........
 
#4 ·
In my opinion as long as you use the correct grade of decent quality oil then there is no need for any additives.

Companies spend millions of pounds developing their oil and I can't believe that if they could make then perform any better that they wouldn't bother doing it!.

I have never been a fan of any fuel/oil etc additives,but each to their own.:)
 
#5 ·
Hi there rodmaker, I have used a product called Prolong, which is similar to Slick 50, in my Lag and as Truckbusuk suggested the car did feel smoother and quieter afterwards. I believe they both coat the moving parts in a teflon like substance which is supposed to reduce wear and tear and friction,
Regards Leroy
 
#6 ·
Hi rodmaker, the mpg was approx 3-4 mpg around town and 5-7 on the motorway ...
I used to be able to do Glasgow - Exeter services with 5 onboard, roofbox and 5 bikes and aircon at 75-80ish on a tank of unleaded until the light flashed (7ltrs)
... so 450miles for 60ltrs or so ... 34mpg, the journey before that was always 27-28 mpg.
That was a Espace2 phase 3, the New Generation Espace (Mk3) was a little better but not much.

So I always reckoned it was worth it

:)
 
#7 · (Edited)
Interesting I have the same opinion as lag.

Never put anything in other than the correct grade of oil.

Even used the cheapest no name oil in some of my early bangers and ran them way past any service periods at times without problems in the engines.

I have yet to be convinced that any additive can coat or plate metal parts to elimanate friction. PTFE or Teflon by another name or vice versa , which is in slick 50 I think? Doesn't last on a cooking pan and that is sprayed and baked on the pot during manufacture. Why would it last in an engine then when in suspension in the oil? Maybe I'm looking at thae process incorrectly? Maybe the tefon is working because the particles are micro size and get in between the moving parts. Is that the secret? Well that WAS my reasoning but see the link below!

A thinner oil will reduce drag on moving parts. For instance - fully synthetic oil, or at least the stuff I have seen, is thinner runnier than mineral or semi synthetic oil. So should give more MPGs

I usually buy Halford semi synthetic . Just because they are handy and nearby, but before that I always used good old Duckhams mineral.

See this site for a slick 50 blasting! Slick 50 and other ail additives If the info is correct and judging by the law suites, it is. Avoid the stuff at all costs!
 
G
#8 ·
I changed to Amsoil fully synth European 5w 40 and it has certainly been worth it. I too have tried additives in the past despite my the fact that my father was a petrochemist and said oils were always made for a specific purpose, perhaps there is some psycological benefits to using additives but if what I've seen in ads showing engines running on empty sumps using certain (US) additives is to be belived then who needs oil anyway!!!!
Have a look at this link
Car Bibles : The Engine Oil Bible
then make up your mind
 
#9 · (Edited)
Looks like I'll sticking to my semi-synthetic.

Like lot of folks who make favourable comments on the stuff they put in their engines you don't qualify your statement. "and it has certainly been worth it"

In what way have you found it to be worth it?

I'm not sure though being fooled psychologically offers any benefit to anyone, other than the seller of the product?
 
#10 ·
I agree with Lagtdi. I use Castrol fully synthetic oil. Expensive but you total protection and you wouldnt need any additives. Having said that, petrol/diesel additives are great in my opinion. They lubricate the upper cylinder and keep injectors clean. If you want to spend money on addittives go for Redex injector cleaner. Well worth the dosh!
 
#12 ·
ive never kept a car long enough for me to worry about engine wear and the need to buy these products.
modern engines are capable of outliving most other car parts anyway. say youve got an engine about 150k miles and have been using the slick50 treatment and are well pleased with yourself, ohoh valve oil seals have just went and warrant big repair to engine, so much for the engine protection promises.
so what im trying to say is (and i may be wrong) , is that all i hear from these products is metal to metal friction reduction and nothing about seal wear which can also leave you with an uneconomical repair for a certain type of car at a certain type of age.
 
#14 ·
i also don't use any oil additives they just seem like a waste of money,if they were any good the oil manufacturers would be using them in their oil!!.
however i do use a fuel additive in my 1.5DCI kangoo as i run up a high milage(125.000 and counting..)but it's not a diesel additive it's a petrol one,my mechanic frend reccomends it as he uses it in his toyota hi-lux 4x4 diesel.
it's called powershot 15k boost,and i certainly feel the diference when it's mixed in half a tank of diesel(approx 20 ltrs)usally every 5000 miles,as injectors are very expensive(£200+)each this stuff keeps em clean with a bit of a power increase thrown in too.
 
#15 ·
Have to agree with the sceptics on this one - I would rather spend the money on a better quality oil or more frequent oil changes. I think the additives got a bad name originally as they tended to be used by unscrupulous vendors to temporarily cure a car of its ills (i.e smoke, rattles, etc), just long enough for it to sell...:d

Paul
 
#16 ·
I'll be the difficult one.
We had a 2000 Holden Commodore VT with 65,000 km on it. I tested the fuel consumption at idle and it was between 1.8 and 1.9 L/h. I added Nulon E30 and it dropped to 1.5 to 1.6 L/h. We kept the car for another 60,000 km and the idle fuel consumption stayed about the same.
I have read many reports that say these additives don't do anything - however this product dropped my fuel consumption at idle and it stayed low for 60,000 km. I can't make any comment on any of the other claims.
This isn't a recommendation, just an observation. YMMV.
Simon
 
#23 ·
I had a range rover with 135k on the clock which had been treated with slick 50 every three oil changes on doing one oil change unbeknown to me i lost the drive to the oil pump

I AM CONVINCED IT SAVED MY ENGINE it took me some time to find the cause on no oil pressure and correct it the engine was run three or four times while trying to find cause and when found and corrected was retreated with slick50 and did another fifteen thousand with out any trouble and had to have nothing done to the engine at all
the person who had it before me had reshelled it and put new rings in and used slick50. the engine had done 150+ when i sold it and still going good without slick fifty it would have possibly been a regrind ect.

John
 
#26 · (Edited)
Hi, John,
So what was the cause of the loss of drive to the oil pump? I can't see your point on a pump not working and slick50s benefits. Are you saying you worked on the enginer, changed the oil (not slick50?) and ran the engine with no oil pump?

So if that is the case it had other oil in it and no slick 50 in it at that point?
Then you put fresh oil in after sorting out the pump and it ran okay? Then you subsequently put the slick50 in. Why? I can't see how that proves anything.

It also seems to have ran okay as the oil was changed three times without using slick50. That's around 15-24,000 miles. Or have I read it incorrectly?
 
#34 · (Edited)
Mmmm black art dabling and witchcraft .... and mechanics :d

I have read all the "results" before .... and after I'd used Slick50 ... and obviously can only comment on my experiences ....

As my previous post stated I got better fuel consumption and it stayed like that for the time I owned the cars ...
The Espace2 did 60000 miles after treatment and never had any noticable issues.
The Espace3 did 50000 miles no issues.
The Clio is on 20000 miles and no issues.
One car I have mentioned in posts before but not in this one was we owned a Volvo 244 petrol, it was treated at 30000 miles and again at 100000 miles ... we sold the car to a taxi driver (in Kilmarnock) @ 237000 miles and never had any problems with it, I saw the car 2 years after we sold it and it was still running (still a taxi, dont know if it was the same engine though.)

So I get the arguement that oil companies would use it if it worked, I get the " tests" that say it makes no difference or damages your engine .... BUT .....
I've used it and I thought it worked ..... :)
I'm sure if it was damaging the engine I would have seen it in the 237000 miles that the Volvo did ...
The only repair the Volvo engine had was the head was lifted to insert a helicoil when I stripped the threads on a sparkplug seat, it had 6000 mile oil (GTX) and filter changes and always did 31mpg ( regardless of how you drove it) ...... nothing else honest. :)
 
#35 ·
Mmmm black art dabling and witchcraft .... and mechanics :d

I have read all the "results" before .... and after I'd used Slick50 ... and obviously can only comment on my experiences ....

As my previous post stated I got better fuel consumption and it stayed like that for the time I owned the cars ...
The Espace2 did 60000 miles after treatment and never had any noticable issues.
The Espace3 did 50000 miles no issues.
The Clio is on 20000 miles and no issues.
One car I have mentioned in posts before but not in this one was we owned a Volvo 244 petrol, it was treated at 30000 miles and again at 100000 miles ... we sold the car to a taxi driver (in Kilmarnock) @ 237000 miles and never had any problems with it, I saw the car 2 years after we sold it and it was still running (still a taxi, dont know if it was the same engine though.)

So I get the arguement that oil companies would use it if it worked, I get the " tests" that say it makes no difference or damages your engine .... BUT .....
I've used it and I thought it worked ..... :)
I'm sure if it was damaging the engine I would have seen it in the 237000 miles that the Volvo did ...
The only repair the Volvo engine had was the head was lifted to inset a helicoil when I stripped the threads on a sparkplug seat, it had 6000 mile oil (GTX) and filter changes and always did 31mpg ( regardless of how you drove it) ...... nothing else honest. :)
Hi If you are happy to use it fine, but I'm not convinced. It might only show that your filters did a good job. The negative test results in the links have me convinced that it is not a good idea.
 
#36 ·
I think what we have showing in the posts is anecdotal evidence of any benifit. Unfortunately it could be argued that the owners of cars that used additives "assume" the additive was the reason their cars kept running well. In actual fact they don't really know this is the case. The cars might have just run as well on regular oil, without any "treatment" from additives.

The negative scientific test results on engines were additives have been used is more conclusive. The engines have been run for the various tests, then dismantled to examine the condition of the components. As far as I can find, all of these tests have condemned the products. Siting for example : "Unsubstantiated scientific and mechanical claims, excessive bearing wear, worn bores, low oil pressure, blocked filters, blocked oilways" etc.

I have been unable to find any "independant" test available on the net, i.e not paid for by the manufacturer of the products - that claims any positive proven benifit.
 
#37 ·
Spoton rodmaker, and I'm not fighting any corners here, you pays your money and takes your choice!.

As a point of intrest does anyone know or have read anywhere (not manufacturers tests) of engines being damaged or expiring earlier than could be reasonably expected after using any of these additives ...

I would think there should be something out there, as its usually the people who percieve a grievance or complain that usually make themselves heard, not the ones who have had no problems ....

Remember the SHELL petrol fiasco about 10 years ago?


:)
 
#39 · (Edited)
I got this from The Engine oil bible: Car Bibles : The Engine Oil Bible



"Apart from the fact that all the additive manufacturers have been in trouble in the past, and most of them have lost their cases (see above):
My views on engine oil additives are this: the oil companies spend hundreds of millions on research and development in order to make their oils suitable for use in car engines. A standard off-the-shelf engine oil is already stuffed with a cocktail of additives put there by the oil company (see above). By contrast, additive companies spend a couple of million on R&D and an equal amount in Page Ranking and advertising to claim that their product (and only their product) will enhance the life of your engine. You're adding an unapproved additive to an already additive-full oil. Spot the problem?

The current trend is the "90% of your engine wear happens at startup" advertising ploy. This fact is absolutely true, but as it happens, it's less to to with "grinding engine parts" and more to do with combustion. When the combustion gases burn, they form acids which are highly corrosive when their vapours condense. These acids collect in the upper cylinder areas where their temperature is raised above their dew point. The acids condense and etch the cylinder walls and piston rings. In reality, this accounts for over 85% of engine wear, the other 15% being down to abrasion. So the adverts are nearly right - most of the engine wear does happen at startup, and it is because of a lack of oil, but it isn't because the oil isn't coating moving parts - it's because it's not transporting these acidic gases away. Having said that, if you start the engine and let it idle for 15 seconds or so before moving off, you can probably add another 100,000 miles to your engine's life without one bottle of additive. This warms the oil up a tad and makes sure it's in all the most vital areas before you start putting a strain on the engine. Most handbooks tell you not to let the engine warm up before driving off (they're referring to the acid corrosion mentioned above), but they mean don't let it reach working temperature. If, however, you insist on starting up and belting off down the road, think of this next time: it takes an average engine around 3 minutes of average driving for the exhaust manifold to reach 300°C. If you blast off and run around at full throttle, right from the word go, that process takes a little under a minute. Think about it - from outside air temperature to 300°C in a minute - what exactly is that doing to the metal in your manifold? Ask anyone who's ever owned an original Audi Quattro - they'll tell you exactly what happens.

I'm not saying that these companies are having us all on, heaven knows there are plenty of statements from companies and private individuals who have reportedly reaped the benefits of these products. But in my experience, it's simply not worth the huge risk of putting the additive in there.

Another perspective:
I received this email from Albert Clark who has, it seems, had first-hand experience of one of the additive products:
I kept hearing about such a product and found a store going out of business that was practically giving it away. I put a quart in two cars: An MGB and a Chevy 305 V-8.
The MGB went 20 miles before a ring stuck causing it to start throwing oil everywhere. A mechanic then messed up when putting new pistons on the old rods and shortly after rebuild a piston froze and threw a rod bearing that ruined the crank, etc.
The Chevy started using a quart every 25 miles immediately after the product was used. I drained it and refilled immediately, but it took engine flush and about 4 oil changes over 2000 miles before oil usage was reduced to a quart every 400 miles. It was using a quart every 800 miles before that. I ended up putting another 60,000 miles for a total of 180,000 miles before rebuild.
I will never recommend such a product to anyone.

The moral? If you're going to care for your engine, do it properly, not in half-measures, and it will look after you for as many miles as you care to drive."
 
#40 ·
Hi, the Shell thing was about 10yrs ago, they introduced a LRP petrol which had an additive which was susposed to help with the change from leaded petrol to unleaded, but what it actually did was to burn out valves, valveseats, melt spark plugs and all sorts of nasty things ...
fuel was withdrawn and reformulated and lots was paid out in compensation for damaged engines ....
Cant be sure but I thought it was called Opti-Max (as oposed to Optimax) or maybe it was an earlier version or indeed its predecessor.
I think the issue basically was excessive pinking in "performance engines" I remember Volkswagen and BMW's being particularly badly effected.

This is from memory so I might have a few things mixed up a bit.

:)
 
#41 ·
Ah ha!

I had a brand new petrol Peugeot 405 . Failed it's first mot on emissions. Turns out the unleaded petrol was causing the valve stem seals to harden allowing oil past into the cylinder. Peugeots remedy was an "additive" that went into the oil to soften and expand the seals. It did work. I had the car for five years. In retrospect though, if I had been smarter at the time, I would have taken this further with the manufacturers.
 
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