Advice: The importance of grease

Watching some of the events at the recent Commonwealth Games is as exciting as watching paint dry. Maybe they should introduce the ancient art of grease gun tossing, a visually stunning spectacle, has been practiced since the introduction of the portable grease gun. For those unfamiliar with this pastime, points are allocated for trajectory and distance. Additional points are awarded for volume, originality and descriptiveness of the accompanying profanities. Howard Shanks explores the phenomenon behind this strange practice.

No doubt you’ll agree that greasing your rig is not one of the more pleasant tasks associated with operating a truck. It is, none the less, one that needs doing and doing well. Now, what do the finer points of grease gun tossing have to do with greasing procedures? Not a lot, but would you have read this far if we’d started the article with recommended number of pumps per nipple? Do read on though, we’ll return to the popular sport of tossing later.

A few months back I purchased a couple of McNaught ‘Flexiguns’, for around $110 each. Over the years I’ve used a whole gamut of different grease guns, most of which ended up somewhere in the next paddock after an enthusiastic round of grease gun tossing.

To grasp the importance of accurate greasing procedures, look through a parts catalogue with pricing. An 1800 series uni that’s not greased properly may only last 15 – 20,000 kilometres. A genuine Spicer uni costs around $140, a non genuine around $90. Now add to that the cost of downtime, with labour at $120 per hour in most workshops. Then there is all an unnecessary expense considering unis should last a couple of years rather than months.

That’s around $250 off your bottom line for that month, or to put it another way, about five boxes of stubbies. I know what I’d rather have! What about the suspension pins and bushes? They’re even more expensive to replace. If the unis aren’t being greased properly, it’s a safe bet the rest of the truck isn’t either. All of a sudden we’re up for well over two grand in unnecessary repairs.

Careful and regular greasing procedures not only maximise component service life, they also provide the opportunity to inspect for potential problems.

Now, back to my new grease guns. I bought two, one to live in the truck and one for the workshop. From an early age, we’re taught that lubricant must be kept free from dirt and dust. I wrap my grease guns in clean rags and store them in a clean environment for this reason. So you can well imagine my disgust when I discovered one of my new grease guns lying in a pile of old junk on the workshop floor.

Dirt and dust finds its way inside the gun, then the bloody thing won’t bleed properly or the trigger mechanism seizes up. Before you know it, you’ll be competing in another grease gun tossing event.

The message is a simple one. Keep your grease gun clean and store it in a clean environment. It is, after all, an expensive piece of equipment used to perform a very important task. Practicing the ancient art of grease gun tossing is a costly exercise. I haven’t seen many grease guns survive a decent toss, especially if I’m the one tossing them.

Facts about Grease
Possibly the best way to describe grease is to consider it as a sponge full of oil. The sponge is the base or thickener that holds the oil and additives in place, giving it the basic properties it requires such as its melting point or resistance to water contamination.

The lubrication properties of grease usually come from a mineral oil because of their lower price when compared to synthetic oils and their easy availability in a wide range of viscosities. Synthetic oils are, however, increasing their popularity, especially where high or extreme operating temperatures might compromise the performance of a mineral oil.

The base of grease is the thickener used to produce the grease structure. There is a wide range of materials used and these include metallic soaps such as calcium (lime), sodium (soda), lithium, aluminium and other metals. Added to these are the complexing agents and non-soap greases such as organo clay, bentone, polyurea, silica, carbon black, dyes and organic polymers.

The final make-up of the grease includes oxidation inhibitors, corrosion and rust inhibitors, extreme pressure agents and anti-wear additives and adhesive or tacky agents.

As a general rule, greases containing more than five per cent of graphite and/or molybdenum disulphide are considered not suitable for high-speed anti-friction, rolling element bearings running at above 1000rpm. However it should be noted that grease containing graphite should not be used on stainless steel, as it will reduce the corrosion resistance of the stainless steel.

Points to remember
>> Temperatures, storage conditions and pressure all combine to affect the structure and performance of grease. Grease should not be left with hollows or depressions but smoothed over in the storage container. Pressure applied in grease guns and other lubrication equipment should be released immediately after use.

>> Avoid the danger of incompatibility when applying new grease to a bearing containing unknown grease. This can lead to excessive softening and leakage of grease from the bearing. It is best to remove as much of the existing grease from the system as is possible.

>> Many factors have an effect on greasing service intervals and these include the manner of driving, wheel balance and different road surfaces in addition to the recommended service intervals. This can be demonstrated by the more frequent failure of the nearside wheel bearing due to camber influences and kerb scuffing when compared to the offside wheel bearing.

The moral of the story is spending about 20 minutes each week putting a couple of pumps of grease in each nipple around your truck and trailer will save you countless hours of downtime and add to your bottom line.

Big thanks to our friends at Castrol for helping with this article.