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Introduction

• Beware that selecting a suitable / proper fluid and filter (oil, coolant, etc.) is vital for the longevity of the mechanical systems which use those fluids and filters!
  • For example, the longevity of the engine, gearbox, etc. is highly dependent on what exact oil type is used.

• Using a high quality fluid from a good manufacturer is one thing, but equally as important is using a properly matching type of fluid.
• However, selecting a proper fluid type can be a rather tricky endeavor, as there can be significant differences among seemingly unimportant specification details.
• For example, the most common misconception regarding oils is that only the viscosity specification is relevant / important.
  • This would mean choosing an engine oil only by looking if it's 10W-40 or 5W-30 or etc.
• Oil's viscosity is just one of its attributes.
• Oils have many other chemical attributes which are equally as important.

• Generally, the petrochemical industry and technology is so vastly complicated in discerning all the types, standards, classifications, ranges, compositions, ratings, regulations, gradings and whatnot, that it is very hard even for professional petro-chemists to discern it all.
  • This is additionally made worse by several "moot" standards and classifications in that industry (example are API GL-x classifications).
    • In short, the industry has never settled on properly formulated international standards about many material and chemical characteristics of petrochemical products, so there are various country-level or even "industry jargon" standards in use around.
      • For example, API classifications are an old American industry rating which has not yet been replaced by anything better designed and with world-wide consensus.

• An additional layer of confusion is of course added by various well-established street-garage myths and misconceptions, which are sometimes "reinforced" by some tricky / slimy official factory claims.
  • Example 1: "A color of an engine coolant determines its type."
    • Even some car manufacturers (Ford for example) refer to coolant types by color when directing their customers on which coolant type to buy!
      • That's because they expect you to select only from their genuine line of their "own" coolant products, and they know which of their colors represent each coolant type!
  • Example 2: "Transmission (gear box, differential) oils should never be replaced."
    • Today many car manufacturers specify their factory filled transmission oils as "lifetime".
      • What they mean in practice is: "Those oils will certainly last until the end of the mileage or time covered under our warranty. After that, we don't care. In fact, we care that you come to us later for an expensive transmission overhaul after that stale worn oil wrecks it!"

• The result of all this mess is that there is a very high chance that everyone except the most proficient users will make a wrong selection of fluids and filters for their vehicle.
• Most alarmingly, the majority of car mechanics are also misled as a result of all these industrial mis-standardisations and street-garage misconceptions, as well as some malicious factory claims.
  • Therefore, your "trusted and honest" car mechanic to who you entrust fluid and filter selection and replacement for your vehicle might be no more educated about the topic than you are!
    • He'll be definitely less educated than you after you read this article!

• Luckily, ordinary motor vehicle users do not need to dive deep into all those peculiarities of the petrochemical and automotive industry.
  • Otherwise, it would have to be a really deep dive indeed!
• As long as a few specific guidelines are being adhered to, an ordinary user can make a proper fluid selection.

Common notes about engine and transmission oils

• Engine and transmission oils can be of mineral composition, semi-synthetic or fully synthetic.
• There is no formal industry standard or classification for this, so generally any oil (for example: "5W-40 ACEA B3" engine oil) can either be mineral, semi-synthetic or fully synthetic. The only way to determine that is to read the description on oil's container, and one of these three should be written in plain English.
• Mineral oils should generally be avoided, as they are generally too much susceptible to many things and influences, and they loose their chemical and physical virtues relatively quickly during use.
  • The only exception to this rule is if your vehicle manufacturer specifies a specific oil viscosity, and only mineral oils are produced in that viscosity.
    • In that case, your choice of oil's composition is more or less pre-determined, as the manufacturer has already counted in that a mineral oil will be used. Just change it regularly.
• Fully synthetic oils should be used whenever a choice is possible, as they generally provide the most chemical and material virtues (depending on quality) and have the longest longevity.
• Semi synthetic oils are a very "moot" category, as there is no definition of what a "semi" really represents in terms or percentages or so.
  • In other words, an oil which is 95% mineral and only 5% synthetic is also called "semi synthetic", with equal rights for that "name" as an other oil which is 20% mineral and 80% synthetic.
  • This "vagueness" in definition is usually exploited in the industry.
  • With semi-synthetic oils, the only rough estimation of what percentage of a semi synthetic oil is really synthetic, is to compare its price with its competition.
    • Higher price should mean more synthetic compounds in it.
  • This is why only a fully synthetic oil is a "safe bet".

• It was written earlier that viscosity figures ("xW-y") of oil are not the only important parameters.
• With engine oils, equally important characteristic is the exact "ACEA" or "API" category of the oil, or the exact vehicle manufacturer's standard which the oil needs to conform to.
  • Either the ACEA classification, API classification or vehicle manufacturer's own classification will be specified for required engine oil in vehicle's owner's manual.
    • Examples: API SH, API SL, ACEA B3, ACEA C4, Mercedes-Benz 229.3, Renault RN0710, Volkswagen 505.00, etc.

• So, to properly choose a suitable engine oil, you need to watch out for three important parameters:
  1. Suitable viscosity (example: 5W-40);
  2. Suitable chemical characteristic classification (example: ACEA B3, API SL, Renault RN0710, etc.);
  3. After you find engine oils on offer which match the first two criteria, it's then your own choice to choose a mineral, semi synthetic or fully synthetic oil among them.

• With transmission oils (for the gearbox, transfer box and the differential), the other very important parameter (except the viscosity figures) is their API chemical classification.
• Using a transmission oil of wrong API classification can wreck the gears and other bits in your transmission!
• So, if the vehicle manufacturer has stated to use API GL-4 oil, make your best effort to adhere to that!
• The difficult part here is that API classifications are quite old and they have been poorly defined from technological viewpoint, so many oil manufacturers now produce "combined" or "enhanced" transmission oils which "exceed" the requirements of these classifications.
• The most common example is a transmission oil which is classified as "API GL-4/5" (non-standard, manufacturer's "classification").
  • This is quite absurd, as API GL-4 and API GL-5 classifications are by definition totally incompatible!
• The other common example is a "classification" called "API GL-4+" which does not exist in any official books.
  • Who knows what that "plus" represents!

• In summary, when choosing transmission oils, after selecting a suitable viscosity, make sure to select an exactly matching API classification.
  • Try to avoid any "enhanced" or "combined" classifications like "API GL-4+" or "API GL-4/5" etc.
    • In other words, if it says to use API GL-4 or if it says to use API GL-5, the safest decision is to use only precisely that one (no "+" or "combo" "APIs")!
• The problem is that proper API GL-4 oils (which Jimnys use for the gearbox and the transfer box) are becoming hard to find these days (as Jimnys were designed in the 20th century you know).
• One of tried and recommended API GL-4 transmission oils Ravenol TSG.

Notes on engine oil filter and engine air filter

• Replace the engine oil filter whenever engine oil is being replaced.
• Engine oil filter quality is important!
  • Cheap, poor quality oil filters can cause 100 times more expensive damage than the amount of money saved when buying them.
• The difference between low quality and high quality engine oil filters is in the following:
  1. The total area of the filtering material;
  2. The porousness of the filtering material and for how long it stays proper as it gets dirty;
  3. The robustness of filter's casing;
  4. The robustness of the connection of the filtering material to the filter's casing;

• Engine air filter should be occasionally checked if it is dusty / dirty.
  • This is especially important if the vehicle is regularly driven on dusty roads.
• A dirty engine air filter can hinder engine's power, cause higher fuel consumption and even long term engine damage.
• Higher quality air filters should have more more filtering area and better porousness of the filtering material, which stays proper for a longer time as the filter gets dirty.

Notes about engine coolants

• The situation with suitable engine coolants is the most chaotic of all.
• In the simplest overall terms, just know that there is no common standard whatsoever about types and variants of engine coolants.
• Also be very much aware that a color of an engine coolant does not determine its type!
  • Determining engine coolant's type based on its color is like determining person's nationality based on their hair color!

• There are various types and private "standards" of engine coolants, and not all are suitable for just any engine!
• In the simplest terms, most Asian (Japanese, Korean, Chinese etc.) vehicle manufacturers use phosphate based engine coolants and they avoid silicate based coolants like poison. They also don't like the presence of a 2-EHA chemical in engine coolants.
  • On the other hand, most European vehicle manufacturers use silicate based engine coolants and avoid phosphate based coolants like a plague. Usage of 2-EHA is also common for European cars.

• Finding a non silicated, 2-EHA free, phosphated engine coolant in Europe is like finding a pig in Teheran.
• Usually the only sources of phosphated, non silicated and 2-EHA free engine coolants in Europe are official service workshops of Japanese vehicle manufacturers, where you should be able to buy OEM Toyota, Mazda, Suzuki, Nissan etc. coolants.
  • As far as it is known, all Japanese vehicle manufacturers use the same basic chemistry composition for their engine coolants (non silicated, phosphated, 2-EHA free, usually HOAT).
    • This is because they all adhere to the "chemical school" of the main Japanese chemical conglomerate, the factory called CCI, which actually usually produces the coolants for them.
  • These OEM Japanese coolants can be quite expensive, or even hardly available.
    • Also, they are usually available only as a pre-diluted mix, which might not be suitable if you want to control a precise mix ratio with distilled water when replacing the coolant.
• The only known aftermarket non silicated, phosphated and 2-EHA free engine coolant in Europe is Ravenol HJC.
  • If you find out about others, please add that info here!

There are imperfect, but at least more or less compatible alternatives in Europe:

• German chemical mega factory BASF has their "standard" G30 which is both silicate and phosphate free, so is advertised as a universal formula for both Europe and Japan.
  • However, G30 contains 2-EHA.
  • German manufacturer Volkswagen also has a similar "standard" VW TL 774 F, which is also called G12+ (note: only one "plus"), which is also both silicate and phosphate free, but contains 2-EHA.

• Since your main goal is not to introduce silicates in the cooling system, both of these coolant types are at least not outright damaging to your Suzuki engine.
• The lack of phosphates might not be such a major issue, since both of these coolant types have other (organic) types of additives which should more or less make up for the lack of both silicates and phosphates.
• The presence of 2-EHA is definitely undesirable, but is still less of an issue when compared to the presence of silicates.

Examples of aftermarket coolants based on BASF G30:

• BASF's own Glysantin G30
• Comma Xstream G30

Examples of aftermarket coolants based on VW G12+ (VW TL 774 F) are plentiful and many.

• However, don't confuse them with G12++ type, which is quite a different type!
• Also, make certain that a G12+ coolant states to be silicate free on the product labeling.

And remember - color of an engine coolant is irrelevant!
But what is relevant is that you perform a thorough flush of the entire coolant system (radiator, expansion tank, engine block, heater core) with plenty of soft or demineralized water before pouring the new coolant in!

Notes on brake fluids

• All Jimnys require brake fluids which comply to a rather old DOT-3 standard.
• However, DOT-4 standard has fully superseded the DOT-3 standard in the meantime.
  • So, if you can not find a DOT-3 brake fluid, it is completely safe and allowed to use any DOT-4 brake fluid (and even recommended).
    • The only major difference between DOT-3 and DOT-4 is that DOT-4 has a higher boiling point, so there is absolutely no reason not to use DOT-4 every time.
  • On the other hand, DOT-5 standard is completely incompatible with any other DOT standard, so do not use any DOT-5 brake fluid in a Jimny!
• DOT-3 and DOT-4 brake fluid compositions are not super advanced chemistry, so in general any manufacturer's DOT-3 or DOT-4 brake fluids should be of completely acceptable quality.

Notes on power steering fluid

• Rarely any vehicle manufacturer specifies a replacement interval for a power steering fluid in a hydraulic power steering system, nor provides a procedure on how to drain it and refill it.
• Common experience from hydraulics mechanical engineers (people who design hydraulic systems in excavators, big trucks and other industrial machinery) is that there is rarely a need to replace a fluid in a hydraulic vehicle power steering system, as the fluid does not endure any high stress in such systems.
• The experience from vehicle mechanics says that the power steering fluid does not need changing even if it is old, until it starts to look dirty (dark-brown) compared to its strong cherry-red color when it is new.
  • When such discoloration becomes noticeable, only then should the power steering fluid be changed.
• The replacement procedure for power steering fluid depends on a vehicle, but it usually comes to some kind of improvisation.

The simplest and safest improvised power steering fluid replacement procedure is:

1. Buy 2-3 times more new fluid than the actual capacity of the system;
2. Perform partial drain of the old fluid from the power steering fluid reservoir with a suction tube;
3. Fill in some of the new fluid in the power steering fluid reservoir;
4. Turn the vehicle on;
5. Turn the front wheels completely left-right a couple of times;
   • It is advisable to use lift jacks to have both front wheels raised above the ground, for easier steering.
6. Turn the vehicle off;
7. Repeat steps 2-6 several times until the color of the fluid in the power steering fluid reservoir is the same as the color of the brand new power steering fluid;

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Page last edited on 20/12/2018 by user Bosanek