As the owner of a 2018 Ram 3500 pickup powered by a 6.4L HEMI and a moderately advanced DIY mechanic, I took it personally when I found myself sitting on the side of the road in western Kansas waiting for a tow truck. Being 400+ miles from home I had no choice but to have it towed to a Dodge dealer. I was thankful that I had purchased the extended warranty that I was sure I wouldn’t need when I completed the purchase just a short time before.

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Having bought the truck used just two months earlier with just over 84,000 miles on the odometer and driving it less than 2,500 miles before launching bump bars in places they shouldn’t be, I felt confident that the failure was not due to lack of maintenance from my side. However, the likelihood of overdue maintenance before I got it is high.

The a typically reliable HEMI engine has a fatal flawits MDS, short for Multi-displacement System, can starve the lifters and pushrods of oil, leads to HEMI Tickand possibly a not-so-fun game of pick-up sticks inside the engine lifter valley. My experience led to a remanufactured HEMI engine. However, it is possible that some simple maintenance could have kept my truck’s engine running longer.

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Your first line of defense against engine failure is to maintain the proper amount and type of clean oil in your HEMI engine. Oil types and maintenance intervals vary between HEMI engines and their different applications, so it’s best to consult your vehicle’s owner’s manual or take your vehicle to a professional for service. For example, some HEMI engines may use 5W-20 engine oil at recommended service intervals of up to 10,000 miles, while others recommend oil and filter changes at less than half the mileage with 0W-40 engine oil.

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If you don’t feel comfortable (or just don’t want to) changing your own oil, it’s still good practice to check your oil level often and especially before driving your vehicle long distances. When checking your oil level is one of the easier ones maintenance tasks you can do at homechecking the other fluids while the hood is up is a good idea. The fluids in question include those for the transmission, power steering, brakes (and clutch if so equipped) and engine coolant.

While it is a simple matter to top off any fluids that are low, it is important to use the correct type for your HEMI. Fluids used by the transmission, power steering and brakes come with specific applications, even the color of your engine coolant can be critical. Again, consult your owner’s manual, a knowledgeable friend, or a trusted professional for advice on fluid types and change intervals.

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To the untrained eye, opening the hood of your vehicle reveals either a vast expanse of impenetrable engine casings or a maze of cables, hoses and covers with warning labels. What you will see depends on your focus and what model of car or truck you are looking at. First, let’s focus on the rubber hoses.

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The hoses on your HEMI engine are visible and easy to inspect (for the most part) under the hood of your vehicle, although you may have to remove some of the engine covers to get to them. The hoses that transport coolant between the radiator and the engine and the heat exchanger in the air conditioning system can deteriorate over time.

You’ll also come across some smaller rubber hoses that transfer vacuum created by the engine to valves that operate various systems around the car. A bad hose in this system can lead to hard to find vacuum leaks. Regular inspections for cracking, bulging or minor leaks can prevent problems such as rough idling and engine overheating.

Your HEMI engine does more than provide power to move your vehicle down the road. It also provides power to charge the battery and electrical system, drive the air conditioning compressor, power steering pump, water pump, and spin the compressor if equipped. It does all this with belts that transmit power from the engine’s crankshaft to the required systems. Most often it is a single serpentine belt.

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If this belt fails, you will lose power steering and air conditioning, and warning lights will appear on your dashboard. Fortunately, before it fails, it often exists warning signs indicating that the serpentine belt must be replaced.

While you’re under the hood checking fluids and hoses, take a look at the serpentine belt on the front of your HEMI. You will look for any frayed edges, cracks or other damage. Like any good story, the Serpentine Belt has two sides. The flat side usually only comes into contact with pulleys that guide it around, called pulleys and those that provide tension, tensioners.

The other side has ridges and grooves running lengthwise. It is this side that transfers the power from the crankshaft to the relevant components. Since it’s doing all the work, it’s under the most stress and usually takes the most damage, so don’t just look at the flat side and call it good.

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The tasks listed so far are generally considered routine maintenance such as should be done every 1,000 to 3,000 miles or as specified in your user manual. The spark plugs, two per cylinder on HEMIs, that ignite the air-fuel mixture inside the cylinders of your HEMI also require maintenance, just not as often as other engine components.

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Although it is possible to remove the spark plugs for periodic inspection, it is not recommended. However, it is recommended that HEMI engine spark plugs are replaced according to the scheme in the user manual.

If you got your HEMI with a few miles on it, you may not know if the spark plugs were changed before you got it or not. In that case, you have to make an educated guess. Since the spark plugs are responsible for igniting the fuel in the combustion process, some of them are signs of bad plugs are rough idling due to an engine misfire, clicking noises from the exhaust and poor fuel economy, often accompanied by a check engine light (CEL).

The appearance of the indicator light on your car’s dashboard is not cause for panic, but it definitely requires immediate attention. The good news is that almost any auto parts store or neighborhood mechanic will check the code(s). who initiated the alert for free. Keep in mind that the free check is often vague and may require additional diagnosis that is not free.

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In addition to the dreaded check engine light (CEL), your instrument panel has other warning lights for battery, oil, coolant, and tires. Some indicate low pressure or charge, while others warn of excessive temperatures. If you ignore any of these lights, you could be parked on the side of the road.

A bonus tip to help keep your HEMI engine running in top shape is use the correct octane fuel. Again, we’ll refer you to your owner’s manual, or maybe the tag inside your gas cap, for the correct grade, but some HEMI engines require more octane than others, some can run on E85 Flex-Fuels, and some can’t.

Using a lower octane than recommended gasoline leads to early detonation, which the engine compensates for by adjusting the spark timing. While that adjustment can reduce detonation, it also reduces engine power, causing it to work harder than it otherwise would have to, which can ultimately reduce the life of your HEMI engine.

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