Lubrication

ďOil Ė Texas Tea Ė Black GoldĒ. So the song goes. Yes, that thick, black liquid that spurts out of the ground or from under the sea is one of the most vital and precious commodities we have. It makes people rich. It makes many people poor in paying for it, but above all, it makes our prides and joys keep on going. Itís also found in nearly every item you come into contact with on a daily basis, things like soap and plastics, but we are more concerned here about itís lubricating properties and why itís so important to use the right one for the right job on our Mahindras.

If you have problems sorting your minerals from your synthetics, your detergents from your anti foaming additives Ė then youíre not alone. Almost every day we see adverts for new technologies and new marketing claims. We are supposed to understand it all based on the gobbledygook on the side of the tin and from these adverts. What is worse, as Mahindra owners and ď so called expertsĒ in the ďclassic carĒ field, we are supposed to know all about this stuff and explain it to those mere mortals who own the latest Euro box!

Well, I thought it was about time to have a handy guide on lubricants, mainly those we should be using on our Mahindras but also the facts and tips to help you clear up the strange world of even stranger types of 15w40 or EP90 Hypoid.

The Basics of Lubrication

The primary function of all lubricants is to keep moving parts from touching each other. When moving parts touch, they wear. They eventually wear to an invisible state Ė i.e. disappear. All lubricants, no matter what they are made from prevent this by forming a layer that separates the parts.

Lubricants do have other uses as well. They serve to conduct heat, carry away contaminates like dirt and small chips of metal and they help seal housings from outside elements. Sometimes, these secondary roles are essential in achieving the primary role for if a wheel bearing wasnít sealed with grease and water was allowed in Ė well, the bearing wouldnít last very long. When you consider what extremes lubricants have to work in, itís no wonder that they only have a limited life span. Differentials can generate a lot of heat, but doesnít collect dirt and the lubricants here mostly wear out because the long chain petroleum molecules in the oil are cut up by the constant scissor meshing action of the gear teeth. On the other hand, engine oil does everything and works in an extreme environment of cold, heat, speed and sudden switching off.

When deciding on how often you should change the lubricants in your Mahindra, itís a good idea for non-engine lubricants to be changed at half the factory mileage recommendation. At the very least, you should stick to the ďsevereĒ recommended intervals.

For the engine however, even more harsh action is required as driving, yes the very thing your Mahindra was designed for, does terrible things to your oil. Not only is this bad, but the length of the drive plays a very important part in prolonging the life of your oil, and your engine. But not driving, or even just pottering to the local shops is just as bad. Humidity that condenses inside your engine will combine with hydrocarbon gases from the cylinders to form acids, which will drain into the sump and circulate with the oil wreaking havoc on both oil and the metals in your engine. You just canít win can you! Well you can prevent the worst-case scenarios from happening by preventative and regular changes of the correct oils and filter. Changing the engine oil on a regular basis is the single most important thing that you can do in extending the life of your engine. Since many Mahindras are only used in the summer, and as second cars, your Mahindra may well be suffering more when itís parked up over the winter than when itís moving. The best strategy for ALL Mahindras is to change the oil and filter every 3000 miles or every six months. In fact, every 3000 or three months would be even better. Just for peace of mind, this surely has to be worth the outlay and is far cheaper than replacing the engine. When you do change the oil, donít be duly alarmed if the fresh oil seems dirty even with a new filter. Remember that one function of a lubricant is to capture contaminates, some of which will be so small that the filter is unable to retain them. A little colour means that the oil is doing its job and the dirt is not staying between the crankshaft and the main bearings.

It does what it says on the tin

To understand how engine oils are rated, you need a degree in Chemistry and Physics, and probably a few more besides. Donít worry about all of the jargon that is written there though, most of it is marketing rubbish, but somewhere on the label is the information that you require to help you choose the right kind of engine oil. Before you do anything else, make sure you choose an oil that is specifically for DIESEL engines and not a general petrol engine oil. The reason behind this is that diesel specific engine oil contains detergents to help clean the engine from the combustion process. Why should we need the engine to be cleaned I hear you ask? Well, think about the principles of combustion. Firstly in a 4-stroke petrol engine there are four separate stages. The most important of these is the firing stage, which is caused by a tiny spark igniting the petrol/air mix. This obviously generates heat, but nowhere near as much as in the diesel cycle. In a diesel 4 stroke engine, the same four stages apply, but at the firing stage there is no spark to ignite the fuel. Instead, fuel is injected into the cylinder were it is compressed to extremely high levels of pressure by the rising piston. This compresses the fuel to such a degree of heat that it explodes, with a greater ferocity than a petrol engine. Petrol needs very little heat to ignite it, whereas diesel needs a huge amount. Itís the reason why diesel engines are made from steel or cast iron and not aluminium. The only problem here is that most of the usefulness of the fuel is shoved straight out of the exhaust pipe before it can actually do the job it was meant to do. Yes, itís not very efficient, but it does provide a lot of power where itís needed, and at a far lower effort rate than a petrol engine. This explosive action creates a lot more muck that needs to be cleansed by the scouring action of the oil and itís detergents. The process of refining diesel also creates problems as diesel is made from all the leftovers after everything else has been made. It is essentially a by-product of the oil industries waste and should be a lot cheaper than the price we pay for it at the pumps. Thank you Mr. Chancellor!

Right, go and make a cup of tea, because this bit gets a little bit technical.

The most important bit of any oil is its viscosity, and this is usually the most visible number on the container. Viscosity is essentially a measure of the lubricants thickness, or how hard it has to squeeze between moving parts.  The standard numbering system used is that employed by the Society of Automotive Engineers (SAE) and the rating numbers increase with the thickness of the oil. A SAE 40 is thicker and more viscous than a SAE30. This is known as a Monograde oil, and you wonít find many of these on the shelves at Halfords, or anywhere else for that matter. Monogrades have the major disadvantage that they thicken at low temperatures and if not replaced with a lower SAE number in winter, starting can be difficult or even impossible. All popular engine oils are now multigrades, which have chemicals added to them to allow them to remain closer to a constant viscosity throughout the changing seasons and temperature changes. When cold, they stay thinner than a Monograde to provide less cranking resistance when starting, and when warm they stay thicker to provide the all important protection between moving parts. A typical multigrade may be SAE 10W40. This means that the oil may thicken to SAE40 in the winter, but thin to no less than SAE10 in normal operating conditions. Simple isnít it? But wait, thereís moreÖ.

Also on the label, there are approval ratings usually from the American Petroleum Institute (API) and the European counterpart, the Association des Constructeurs Europeens díAutomobiles (ACEA). These two organisations set the standards to which all lubricants are tested and any reputable product should be clearly labelled with the results.

API ratings currently for both petrol and diesel engine oils are rated with two letters. Petrol start with an S, while diesel start with a C. Both the second letter denotes the level of test severity and the higher the letter, the more severely tested the product is.

ACEA ratings start with an A for petrol, B for passenger diesel (what we are concerned with) and E for heavy-duty commercial diesel Ė trucks and buses etc. The top standards are A3, B3 and E5. A very highly rated oil may well show the legend ďAPI SL/CJ; ACEA A3, B3, E5Ē. These ratings measure the effectiveness of each oilís total packaging of chemical additives in combating contamination, foaming, oxidation, waxing and so on. So while oils may vary by brand, all must meet a minimum standard of performance to pass the very stringent tests. Choosing an engine oil then is very much a matter of matching the viscosity and quality rating supplied by the vehicle manufacturer and perhaps even deciding that you want to go one better. For example, our engines are designed to use a SAE30 oil with an API rating of CC. Modern day conditions may well dictate that this be upgraded to at least a SAE10W50 rated at CJ or at the very least a SAE15W50 rated CJ. The important thing to remember is to keep or exceed the upper number, 50 in this example. Donít worry if you canít find the latest API number either, as each new quality standard builds upon the requirements of the previous one and all are backwards compatible with their predecessors. There are some complications however with older engines, thankfully our Pug 2.1ís donít count here, but basically, some pre war engines were made with components that react with todayís modern additives. Specialists like Penrite and Castol however, keep manufacturing oils for these cases and will happily recommend which one to use.

There, that wasnít so bad was it?

To synth or not to synth?

Anyone who has bought engine oil over the last few years will have noticed the increasing and sometimes bewildering variety that is now available. Primarily the choice between Fully Synthetic, Partly Synthetic and Mineral is what we are interested in here.

Synthetic oils may not be the be all and end all that the manufacturers say. They do however have several benefits. The most simple and obvious being that they reduce internal friction, which makes it very appealing to high performance cars and racers. Rolling Road tests have shown that power at the wheels can be increased by up to 8%! Synthetics have a high ďclingĒ factor, which means they are very reluctant to let go of the metalwork they are clinging to. This aids start up and, dare I say it, run dry situations, but their main advantage is that they offer a superior flow at low temperatures and resist decomposition and loss of viscosity at extremely high temperatures. However, as always there is a downside and this is most important to us Mahindra owners. Synthetic oil by its very nature contains a very high proportion of detergent. Well thatís good for us diesel engine owners isnít it? Well, no! You see, the higher content of detergents helps to break down oil deposits that are helping to seal vital gaskets, rings and valve guides. This can start or even increase fluid leaks. There are also concerns about the reduction in oil pressure that using a synthetic oil produces because of the wider internal clearances in our engines. The only real benefit for us to use a fully synthetic oil would be to reduce the number and frequency of oil changes, and you must weigh this against the possibility of fluid leakage at the most important places. Iím not saying that you canít use it, but the benefits for our vehicles are neglible, especially as most only see occasional use and never reach more than 60 MPH! You see, for us Mahindra owners, we have a simple design that was meant to use simple technology and simple lubrication. The same applies to Semi Synthetic, and again the cost simply outweighs the overall benefits.

Stick to good old-fashioned mineral oil and change it more often. Itís what your engine was designed for and there is nothing wrong with that. The general rule of thumb here is that if your vehicle is used a lot, and I mean everyday, is free from any sludge Ė most Mahindras are not Ė in sound mechanical condition and given a regular long distance thrashing, Synthetic oil may be of some benefit. If your vehicle is used only occasionally, has a high mileage and by this I mean anything over 20k, as the engine will have been worked hard by the Kia fitted gearbox, which makes 20k equivalent to 120k, stick to high quality mineral oils.

And now a quick word about oil additives

On a recent trip to Halfords, I came across over two dozen different types of oil additive. Some were claiming to reduce friction, others claiming to quieten noisy engines, but the truth is that not one of any of these products was endorsed or carried the name of one of the major oil producers or motorcar manufacturers. Now despite your personal opinion of the oil producers, and most peoples thoughts run along the same lines of money grabbing illegitimates, you have to admit that they know how to make money and if there was the remotest chance of grabbing a few pence from any sale, they would be on it quicker than the average man would last with a page three model. Do you not also think that if these additives were of any real benefit, the likes of Ford, BMW, and Mercedes or any of the Japanese manufacturers would be marketing it themselves? The point is that they donít because they simply donít work to any real benefit. On the other hand, there is an argument that substances like Colloidal Graphite can offer a protective coating on start up, this is where most engine wear occurs, but it wonít pass through a modern spin on oil filter. Molybdenum as found in most oils does at offer the same protection and pass through the filter. The choice is entirely up to you, You certainly wonít be doing any long term damage to your engine by using additives, but you wonít be doing any long term good either, just pouring your hard earned cash into somebody elseís pocket.

Some of the other lubricants

Equally important are the other lubricants that help keep our Mahindras on the road. Itís also vitally important to use the correct one as certain types can damage the internal workings of the components beyond repair.

Gearbox oil:

 This is the lubricant that is used in final drives, gearboxes and most steering boxes. Not all gearbox oil is the same as we are about to find out, and again itís important to use the correct one. Gearbox oil carries a higher viscosity rating than engine oil, but because the ratings are applied differently, it can still be poured out of the can and it doesnít have the consistency of treacle. This is why a SAE 140 gear oil is thin enough to be poured. Like engine oil, gearbox oil can be mono or multigrade, synthetic or mineral. Final drives require a totally different gearbox oil, which is a lot tougher and is known as Hypoid or EP gear oil. The elaborately carved teeth of the final drive unit, diff to you and me, allow the gears to carry incoming power to meet the gear carrying power to the axles (half shafts) from the bottom and not the centre, putting more force, coupled with a shearing action on the gear surfaces. The oil used here must be able to withstand this shearing action as well as the extreme pressures, which is where the EP comes in (extreme pressure). These EP oils usually need copious amounts of additives to bulk them up. The most used additive is sulphur Ė ever noticed the smell! The unfortunate part of these additives is that they can play havoc with certain types of yellow metals (Phosphor Bronze) that are found in gearboxes. This is why a different oil is required for different parts of the transmission and final drive units. Add to this the fact that Hypoid/EP oils have a rating of GL4 or higher and non additive or non hypoid oils have a rating of GL1 just adds to the confusion. Basically, the ratings apply to the testing process, and as long as you use a rating of anything above GL2 where it is required, no permanent damage will occur. The simple rule is to use the correct TYPE of oil in the correct COMPONENT. Sometimes a manufacturer will specify engine oil for use in the gearbox Ė Range Rover (old shape) springs to mind, but as our vehicles donít use this in the gearbox, we shall not concern ourselves with this here. Automatic gearboxes use ATF (Automatic Transmission Fluid), but again as most of our vehicles have manual boxes, we shall not dwell on this.

Greases:

These come again in a multitude of flavours, but itís worth remembering that Mutlipurpose Grease is exactly what it says Ė Multipurpose! Itís suitable for both chassis and wheel bearing lubrication, as well as the propshafts and spring areas.

Copper Grease provides some protection from corrosion in non-moving parts, especially steel/brass nuts and bolts. The copper provides some protection on the threads when the petroleum carrier is wiped away. You should never use copper grease on any moving part though, especially wheel bearings as they can seize without warning with disastrous consequences.

Silicon grease is very handy for sealing spark plug boots Ė not that many of use have spark plugs in our vehicles, and for also sealing wiring connections, of which we have plenty!!!

And finally, some handy advice

Ok, so Iíve babbled on with enough science and if you are still with me, then well done and take a short holiday.

Enjoyed that? Right on we go.

These are a few tips to keep your Mahindra on the road, or at least to stop it from packing up and costing you a fortune in repairs, which should never have happened if you were a bit more careful in the first place.

What you use isnít nearly as important as long as you stick to the right product from a major and quality brand. There is a huge difference between Tesco multigrade at £5 for 5 litres and Duckhams/Mobil at £15 for the same amount Ė think about it! As long as you keep to this rule, then they will all do a reasonable job, and this is why they are major and quality brands. The key here is frequent replacement. Oil doesnít fail because itís of an inferior quality, Iíve been using Halfords own brand in DR.X for years without any problems, but I change the oil religiously every three months. No, oil fails because itís dirty or its viscosity has vanished after exposure to excessive temperatures.

Oil cannot protect if there isnít any oil in there to begin with. Might sound obvious, but you should check your oil levels once a week, and more often if there are any leaks. Unless you know otherwise, check the oil level before you start the vehicle and when the engine is stone cold. Make sure the vehicle is on the level. If when you are checking the oil, itís dropped to roughly two thirds of sump capacity, change the oil straight away as what is left has to work extra hard to provide the same amount of protection and it means that the old oil is being burnt off as itís lifeís usefulness has finished. Topping it up with fresh oil will not make any difference, as the old oil will simply thin out and contaminate the new oil to the same degree as the old oil and you have just poured a couple of pounds worth down the exhaust system. Change it! If you change your oil regularly, you should never get to the stage where you need to top up by this amount Ė except in an emergency - unless you have a leak from somewhere. In either case, itís best to sort out the leak and still change the oil.

On the other hand, donít worry too much if you pour a little more in the engine than is recommended. The Manual might well say that overfilling can lead to damage, but what it really means is that overfilling it by an extra half a gallon and not a couple of extra millimetres will do this.

When the vehicle is not being used for long periods, especially over the winter, get it nice and hot and run it for at least thirty minutes every month at fast idle. If your fast idle is not working, then jam a wooden clothes peg in between the throttle and the throttle stop on the fuel pump and this will suffice. If you can only run it for five minutes, then itís best not to run it at all, but wait until you have the time for a proper blast. It goes without saying that before each period of lay up, you should change the oil and filter, running the engine for the prescribed 30 minutes so the new oil can circulate to every crevice in the engine and again when you are going to start using it for the summer months. Might seem like overkill, but if you have been following all of this, you will remember what non-usage can do to your engine. Short runs are bad for your engine because they increase blow by pressures in your crankcase and place more water into your exhaust system, which will rust it out in double quick time.

When you stop your engine, donít blip or rev the engine no matter how briefly, but let it run for a few seconds at tick over. Blipping the throttle will cause oil, under pressure to lodge in between the piston rings and congeal into a semi hard form. This in turn will cause the cylinder bores to rapidly wear when the engine is next started.

Health and Safety

It wouldnít be right not to include a few words on Health and Safety.

Firstly, old oil, especially old engine oil is carcinogenic. This means itís very dangerous to your health and exposure to your skin can cause cancer. Be warned and use rubber or latex gloves when draining your old oils.

Secondly, itís a serious offence in law NOT to dispose of used oils and filters safely. Pouring it down your drain is a giant no-no and you will face severe fines and/or imprisonment if you are caught doing this. Apart from anything else, itís not the right thing to do as it will eventually find its way to the nearest watercourse and cause all sorts of pollution. Take your old oil and empty filters to your local council tip. They have the facilities there to dispose of it free of charge, and you can walk away knowing you have done your little bit for the environment and saved a couple of Whales into the bargain.

And now, the correct oils and lubricants to use on and in your Mahindra

Item to be lubricated

Frequency

Quantity

Lubricant Type

Grade/Rating

Chassis Bearings

Each 2000 Kms

As Reqd

Multipurpose Grease

Spring Shackle Bushings Ė Spring Pivot Bolt Bushings

Without Lube fittings Ė No lubrication/ With Lube fittings every 2000Kms

As Reqd

Multipurpose Grease

Prop Shaft U/Jís

Check each 2000 Kms

As Reqd

Multipurpose Grease

Front Axle Shaft/Steering Knuckle Housings

Check each 2000 Kms Ė Change every 24000 Kms

As Reqd

Multipurpose Grease

Steering Gear Housing

Check each 2000 Kms Ė Change every 20000Kms

As Reqd

Straight Gear Oil

SAE 90 Ė SAE 140

Steering Relay

Check every 2000 Kms

As Reqd

Multipurpose Grease

Track Rod Ends

Check Every 2000 Kms

As Reqd

Multipurpose Grease

Rear Wheel Bearings

Each 2000 Kms

As Reqd

Multipurpose Grease/ Wheel Bearing Grease

Front Wheel Bearings

Disassemble to lubricate each 12000 Kms

As Reqd

Multipurpose Grease/Wheel Bearing Grease

Transmission and Transfer Case

Check every 2000Kms/Change Every 20000Kms

As reqd/3ltrs

Straight Gear Oil

SAE 80/SAE 90

Front Differentials

Check every 2000Kms/Change Every 20000Kms

1.2ltrs

Hypoid Gear Oil

SAE 90EP

Rear Differentials

Check every 2000Kms/Change Every 20000Kms

1.2ltrs

Hypoid Gear Oil

SAE 90EP

Speedometer Cable

Disassemble to Lubricate Each 24000Kms

As Reqd

Graphite Grease

Light

Handbrake Cable

Disassemble to Lubricate Each 24000Kms

As Reqd

Graphite Grease

Light

Air Cleaner

Change Each 4000Kms

0.6ltrs

Diesel Specific Engine Oil

SAE 10W30 to SAE 15W50*

Engine

Change Each 4000kms

4.8ltrs (Incl. Oil filter)

Diesel Specific Engine Oil

SAE 10W30 to SAE 15W50*

*Please note that these grades of engine oil should be the minimum and maximum for the engine. Anything in between will suffice, E.G. SAE 15W40 etc. These ratings are a guide for UK usage. For the rest of the world, well it all depends on how cold your winters are and not how hot your summers are. If you regularly have winter temperatures below Ė23 Celsius, use a SAE 5W20 for the winter period, and change to the above grades for the summer. It also goes without saying that if you run your Mahindra in hot, dry and dusty/sandy climes, your oil and lubricant changes should be much more frequent.

My thanks go to Dale Drinnon of Practical Classics magazine and Castrol Oil for their assistance in preparing this feature.