Engine oil additives - any not to use ?

[charentejohn]

Just a general question on these.
I don't want to open up the usual debate on whether additives are a con or genuine, hundreds of (tedious) posts for and against all over the internet so that is not the point.
I am more interested in actual reasons not to use them, always up to people to decide if they want to spend money on these or not. No problem unless they cause more harm than good.

A current favourite is ZX1 which I am planning to add to my 2001 HDI 90 engine. Anyone got any info on why I shouldn't.
As ever the manufacturers say good for all engines and does not damage cat exhausts, but they would wouldn't they.
I bought it because I was looking for a Merc W124 at the time and would definitely have used it there, no cat, low tech etc. But for an HDI ?
I believe in additives in general and have used ZX1 in cars before with no ill effects but always older models.

I have personally used Lucas stop leak on my old 'smiley' Transit and it cured a severe oil leak. That said I used it as rebuilding engine not an option as van only worth about £500 if that, but it still goes and is ok for now.

Best honest 'review' I ever read was a long time ago when 'Hot Car' had a mini engine on a test bed at constant rpm for a number of days. Before switching off, having done their tests, they tipped half a can of Wynns or Stp (can't remember) into it. They then said that over the following few hours the revs kept creeping up, their conclusion was to say, possibly due to reduced friction ? make of that what you will.
They just reported what they saw.

The negatives for ZX1 are that it damages copper, EGR unit and cat converters (both denied by company) so would this be the case for an HDI ? I doubt any ill effects would be immediate if the doubters are right. That is after a few weeks the cat and Egr fail and oil starts pouring from all copper joints, I would be using this to increase engine life so long term any information.

Please don't use this for and 'oh yes it is' - 'Oh no it isn't' argument, just actual experience from yourselves or people you know ?

[mlkey]

Worth a shot if you are trying to fix a specific issue, if it is all about protecting the engine invest the money in better quality oil.

I have just had major success curing a misfire during warm up using a flush followed by an oil change and a hydraulic lifter treatment. The suspected cause was a hydraulic bucket sticking.

[Northern_Mike]

Just a general question on these.
I don't want to open up the usual debate on whether additives are a con or genuine, hundreds of (tedious) posts for and against all over the internet so that is not the point.
I am more interested in actual reasons not to use them, always up to people to decide if they want to spend money on these or not. No problem unless they cause more harm than good.

A current favourite is ZX1 which I am planning to add to my 2001 HDI 90 engine.

I would point the honourable gentleman to this thread :

http://www.honestjohn.co.uk/forum/post/ ... tm?t=88196" onclick="window.open(this.href);return false;

There's a long post just after 1/2 way down the page with good info.

and this one

http://www.gtr.co.uk/forum/31913-extralube-zx1.html" onclick="window.open(this.href);return false;

Pay particular attention in the 2nd one to the thread by "oilman".

I believe my engine was designed to run with OIL in it, not substances with foreign particles in it, however small. There's a lot of fine oilways to block up in an engine, especially if these particles really do "bond to any metal surface"...

I would never put anything like this in any of my engines. Good oil is all that is needed.

[Northern_Mike]

Worth a shot if you are trying to fix a specific issue, if it is all about protecting the engine invest the money in better quality oil.

I have just had major success curing a misfire during warm up using a flush followed by an oil change and a hydraulic lifter treatment. The suspected cause was a hydraulic bucket sticking.

I repaired the same fault on a Jeep Cherokheap 3 years or so ago by draining half the engine oil off, topping it off with diesel, and driving around with it for a couple of days like that. Rattled like hell when I got it. Quiet as a mouse after 2 days.

Most, if not all additives bar the Forte Stop Leak thing seem, in my experience, to be snake oil.

[charentejohn]

I had seen the Honestjohn one but not the other. That's the problem as the HJ one is just oh yes it isn't type arguments, no actual data. The comments from Oilman are all over the net (I assume he is an oil designer/chemist and not the lube guy at a garage) and he is opposed to all additives.
He may be the person here http://www.bobistheoilguy.com/forums/ub ... er=1625650" onclick="window.open(this.href);return false; as this mentions the same thing. A good writeup on oil in any case.

Problem is veryfying what people say, when he spoke to 'the Silkolene chemist' he was told these damage engines ? Which Chemist was that and where did he publish his findings. If you search for Silkolene chlorinated paraffin the same text is found in loads of forums etc, strangely though can't find a reference from Silkolene manufacturers site.

If someone has a link to an actual site that has published any findings then I would be very interested. Better than personal anecdotes now that I think about it.
Surely car and oil companies must have tested additives and be willing to at least say 'do not use in our cars/oil products'. It would help if they did stick their necks out and say this, they don't have to risk libel, just say they don't recommend additives in their cars ?

[charentejohn]

Just sent a mail to ZX1 to ask them to confirm all ok for an HDI, and to say what chlorinated paraffin is used for, if it is.
I await a reply, should take a couple of days I guess. I gave them a link to here but asked them not to post directly as it is a general forum, I will let you know what they say.

[Peter.N.]

I'm sure all these additives will do something but an Hdi engine will do 300,000 miles + on ordinary oil - -providing its changed often enough, unless as mentioned an additive is used for a particular purpose.

Peter

[SaabC5]

Me personally, i use the best quality oil i can afford at the time and maintain a strict oil change regime. The only additive i use is a bottle of Forté engine flush probably every 3rd oil change. I'm of the opinion if all these additives really did work then oil manufacturers would put them into their oil in the 1st place as a selling point.

[Peter.N.]

I use the cheapest oil I can find with the correct spec, never worn an engine out

Peter

[Norlander]

Wouldn't do it nowadays with engines being more fussy, but I'm pretty sure that after I changed the worn (but having no noticeable effect on how the engine ran) camshafts on a Citroen GS in the 1980s, an addition of both Slik-50 and Molyslip to engine oil afterwards did protect the cam lobes from wear ... suspected the wear -- which afaics from looking in scrapyards the left side was especially prone to -- was caused by oil draining off while static, and that side happening to be furthest from the pump so a bit starved of oil at startups.
Could be I was just lucky and had (eventually) found a particularly good set of nearly-new camshafts, though.

[addo]

I'd suggest the OP not add anything to the motor other than oil, and keep track of the "savings" over twelve months.

The net amount saved can then be spent on a pressie for the other half...

[CitroJim]

I'd suggest the OP not add anything to the motor other than oil, and keep track of the "savings" over twelve months.

I'll go along with that but will add a tale of a Volvo for what it's worth...

I once had a Volvo 340 that had done a huge mileage and without an oil change for most of it. I changed the oil and it then knocked. I chucked in a can of Wynns and new cheapo 20W/50 and it was quiet again. When it started knocking again I drained the old oil, added another can of Wynns and refilled with 20W/50.

It went on like this for another 20K and it wasn't what killed the car in the end...

So as mlkey says, worth trying if you have a specific issue... But otherwise no.

[mlkey]

I'm of the opinion if all these additives really did work then oil manufacturers would put them into their oil in the 1st place as a selling point.

Oils are loaded with detergents which provided the oil changes are performed regularly, are sufficient. When the oil starts to wear and the detergents break down, the build up starts. Most of the additives would be too aggressive to be a permanent feature in the oil, and are designed to work when the engine is not under load and in a very short space of time.

[Old-Guy]

I would add my vote to the "just use oil of the correct spec and steer clear of all additives unless it's as a short-term solution to a specific problem" lobby.

I prefer to buy relatively cheap oil (not heavily advertised) of the correct spec and change it every 6 months (3-4,000 miles) as I/we rack up most of our miles on the M5, but 95% of journeys are short - very unkind to any engine; so I change the oil . I would also observe that any major oil company has a lubricating oil research budget many many times that of any additive producer.

The only time I have used an oil additive was in the re-built back axle of a Sunbeam Alpine Mk1 (Hilman Minx with no roof an two seats!) - I had to guess the pinion bearing pre-load and erred a bit on the slack side, the resulting whine was a bit embarrassing - but half a can of STP produced blissful silence for the couple of years that I kept the car.

That said, when I worked for Lister Diesels, all new engines were tested (and the big ones run in) using a special moly-based oil that was drained out before despatch (magic stuff much in demand locally for running-in rebuilt car engines!), customers filled the engines with straight HD oil of the appropriate grade for the climate/season.

[Citroenmad]

You have to be careful which oil flushes you use, as some lack any lubrication properties and the manufacturers recommend only to idle the car and not drive it with the flush inside. Now I would question the risks of using such an engine flush.

Some high quality flushes do contain lubricant and that is what you want, you can then drive the car and give it a proper flush, which will free of any sticking lifters etc and free all the dirt off the engine and into the oil. It can be quite amazing, a car which has clean oil before the flush then has pretty black oil after, as all the crap and contamination has washed off the inside of the engine and into the old oil.

Some engines, such as Audi/VWs 1.8 20v engine, are not recommended to have a flush used, as the oil strainer is too tiny to allow any larger bits of dirt through.

As for oil treatments, unless you have a specifi problem, such as a knocking, excessive oil consumption etc, then just the right grade of oil and a good quality oil will be ideal. If you think there is a problem with it then try and find a specific product to fix the problem. Its often a good idea to see if a smal, cheap bottle of potion will cure a potentially time and money consuming problem.

Engine flushes and engine oil additives, along with fuel additives, is very big business. More main dealers use it than you would think, some manufacturers even recommend certain Forte products to cure known problems.

Im biased to the make of additives I use, but they are the best! Ive seen the results and thats good enough for me to use them, but only if there is a problem you want to try and cure. As for engine flushes, I always use a Forte one on every service, why put clean oil into a dirty engine! The oil stays cleaner so much longer.