The Truth About Additives  

by amanda nealy

My article a couple of weeks ago on the subject of engine oil additives drew a gratifying amount of positive reaction. Therefore, it seems appropriate that I should continue with an assessment of other additives that are available off the shelf. I have also been asked to explore the subject of synthetic lubrication and I will get to that in the near future.

People, perhaps, don't realize that after the Second World War, Britain remained on rationing until the early fifties and that cars were just about as precious as diamonds. There was huge amounts of money to be made selling used cars, as Bernie Ecclestone soon realised as he went on to parley a "bomb site" flat lot used car operation into a stranglehold on Formula One. That took money!

Every Austin Ten or Vauxhall was towed out of the field it had occupied for the last six years, polished up and offered to the public as "One owner, nearly new". In many cases, there was some work to be done first to make the car a "good runner". Radiator leaking? Drop in a couple of egg whites. Gearbox noisy? A little oatmeal will do the trick. Differential moaning? A peeled banana was good for a week or so of silent running. So began the development of automotive additives and many of todays products had their beginnings back then.

That's not to say that todays products are as crude and short term as bananas or eggs, far from it. Many of them are very useful indeed. Let's take a look at some of the more popular ones:

Radiator stop leak. These products don't work very well, last only a short period of time and are strictly a "get you home" last resort solution to a leaking cooling system. The problem is that they have a strong tendency to block off the heater core and the small passageways inside the engine. Usually the thermostat sticks open shortly after this stuff is poured into the radiator filler opening. Use it in a dire emergency if you have to, but there is really no substitute for a rebuilt radiator installation.

Power steering additive. Adding power steering lubricant to your reservoir is useful for a secondary reason. In addition to helping the life of your pump, it also contains "seal swellers" that will help prevent leaks from the pump seal as well as the rack & pinion seals. In some cases, the evil day of repair can be postponed for some time. However, if your spring check up reveals a leaking power steering system and you plan to take the whole family on a very long journey, have the leak repaired properly. An additive of this kind can let you down badly at just the wrong moment and leave you in the hands of the tow truck bandits out there on the Interstates.

Water pump lubricant and coolant conditioner. Not a bad idea, certainly won't do any harm, but if you really want to help your pump and radiator to survive, go to the trouble of using distilled or ionized water in your 50/50 mixture. Especially if you have a GM vehicle using Dexcool. This latter "long life" coolant reacts very badly when in contact with chlorine, as many a dealer has discovered of late.

Brake fluid. Don't even think about it. The only way to keep brake fluid fresh is to have it flushed every 3 years or so.

Transmissions. If a transmission hasn't had the prescribed changes of Automatic Transmission Fluid (ATF) and carbon build up is evident, it may well be too late to change the ATF. At which point a transmission tune up additive will help the internal hydraulic seals recover some of their flexibility and may add another year or so to the life of the transmission. There is no substitute for ATF changes at prescribed intervals, but if you bought a second hand car that hadn't been properly cared for, a conditioner is a very useful way of putting off the evil day when a remanufactured unit will be required.

Fuel tank stuff. Unfortunately, the info-mercial crowd has somehow managed to render everyone paranoid about fuel injectors. Let me be clear about this. FUEL INJECTORS ARE THE MOST RELIABLE COMPONENT IN YOUR ENGINE. More reliable than spark plugs, high-tension wires or distributors. They rarely, rarely need any kind of attention and injector cleaner is the most over sold, over rated additive to ever be offered to mankind. (After engine oil additives of-course). The oil companies already put fuel system cleaner in every litre you buy. In our shop we see about 1200 cars a year. We do professional injector cleaning on about five engines per year. And then only because our scope tells us to. Otherwise, it's a waste of time. The orifice in the end of an injector is about the same diameter as a human hair. The astringent, abrasive character of injector cleaner enlarges this hole over a period of time. Since your on-board computer doesn't know this, it will continue to tell the injector relays to open wide and thus provide a rich fuel mixture. Then the oxygen sensor calls for the fuel supply to be cut back. Once that's at a minimum, the check engine light comes on. New injectors cost about $165 each - a little more than the cost of the fuel you thought you were saving.

By comparison, gas line anti freeze is a good idea in very cold weather. This winter, we have solved quite a lot of emergency tow-ins with the judicious application of some isopropyl alcohol. Methyl alcohol, by the way, should not be used in modern engines, unless the owners manual says that the engine is designed to run on gasohol. Up to 8% alcohol in fuel is acceptable for all engines, as is the case, for example, at green pumps in Ontario.

Gearbox and differential additives. We will cover the topic of synthetic gear lubricants in a later article. Nothing else is going to do much good.

Conclusion. Recently I had a very nice old gentleman walk into our shop with a bill for over $370 that he had been charged for a 24,000 kilometre check up. He asked me to see if all that had been done was necessary. The invoice showed a total of $55 for additives. When I asked why this was so, the gentleman replied that he had been told that were necessary to the health of his car.

Actually, they were healthy for the service departments' bank account and very detrimental to the bank account of this client, particularly in an almost brand new car.

Let the buyer beware.

About the Author

Amanda Nealy is a 26-year-old proprietor of a local car rental service in Montgomery, Alabama. Amanda is the daughter of an automobile designer, and inherited her father's passion for cars of all kinds. Know more about toyota spare parts.