How To Maintain a Diesel Engine

Most diesel owners don’t just drive around for fun on the weekends.  Diesels are work trucks, whether towing, hauling, or over-the-road (OTR) commercial transport.  One big difference between a diesel and a normal passenger vehicle is the maintenance schedule.  You can often be a little tardy on the scheduled maintenance for a gasoline passenger vehicle without adverse effects.  A hard working diesel won’t offer the grace period.  If your diesel is a commercial vehicle, or is used to tow as it was designed, stay vigilant on the routine maintenance to ensure long-term durability.  From diesel engine oil to the right heavy-duty filter, keep your diesel engine running smoothly.

Diesel vs. Gas Engines

If you’re not familiar with the routine maintenance on a diesel, it’s not the same as a gasoline engine.  Most of the time, routine maintenance will consist of frequent oil and filter changes.  This is true on all fluids keeping your diesel cool and lubricated.  Would you consider a semi-truck the same as a 1-ton dually diesel for maintenance requirements?  If you don’t, you’d be surprised at how similar they are.  And keeping a semi-truck on the road is easier than you may think.  If you drive a semi-truck, keeping it on the road is key for profitability.  AMSOIL can help you increase your semi-truck durability while decreasing your fleet maintenance costs over time.  It’s a bold statement, but here’s how to do it:

Diesel Engine Oil and Filter

AMSOIL Diesel Engine Products

The quickest thing that comes to mind when you consider routine maintenance will be engine oil and oil filter.  Your semi-truck should have the diesel engine oil changed around every 25,000 miles.  It fluctuates based on the model of engine and the age of the truck.  Newer semi-trucks are pushing past 25,000 miles with the help of technology.  The key is not to push past the limits of your truck’s engine.

If you run a commercial business you may put 2,000 miles on your truck every week.  It doesn’t take long to rack up 25,000 miles on the odometer.  And that 3 months can show up sooner than you expect.  The average cost of an oil change including filter is around $300 at a local truck stop.  They’ll also check all your grease points, your belts, other fluids, and more.  If your semi-truck requires 12 quarts of oil (3 gallons), most of the cost of the service is tied up in labor.  The better option for your business is to change the diesel engine oil and oil filter yourself.  Be sure to use a better oil that will protect your investment.  Consider moving your semi-truck to AMSOIL Premium Diesel Oils.

AMSOIL Premium Diesel Oils

These will offer 4x better cold-temperature performance when compared to a conventional SAE 15W-40 oil.  They also offer excellent viscosity control and outstanding extreme-temperature performance.  You can run heavier loads pushing your semi-truck and best of all it will not void any warranty.  AMSOIL Synthetic Diesel Oil gives you the option of extended drain intervals that push past the limits of a conventional oil.  More miles on the road, less time in the shop, and less worry in worth the upgrade in diesel oil.

AMSOIL Oil Filters

As a perfect partnership, AMSOIL offers a line of EA oil filters.  They allow you to run the maximum miles between oil change intervals.  AMSOIL EA Heavy-Duty Extended-Life Oil Filters (EaHD) provide maximum filtering efficiency and high contaminant capacity for heavy-duty on- and off-road diesel applications.  Imagine driving the maximum drain interval recommendation with AMSOIL synthetic engine oils every time you’re on the road!  These intervals shouldn’t exceed one year, but they increase convenience and reduce maintenance costs year over year.  Why stop at every 25,000 miles for an oil change when the right diesel oil and filter allow you to run well past that?

AMSOIL Bypass System

One addition that many semi-truck drivers and fleet owners never consider is a Heavy-Duty Bypass System for their diesel engine oil.  The system partially filters the flowing oil as you’re driving.  It also removes over 97% of contaminants that build up in the diesel engine oil.  The kit comes with all parts needed to make the installation easy to complete.  Likewise, it allows your diesel engine to run up to 125,000 miles or one year between oil changes.  The kit costs around the same or slightly more than a commercial oil change at the truck stop.  But it allows you to run 5x longer between oil changes.

That’s hours that you don’t have to wait between shipments.  It’s also better fuel efficiency, and less buildup in your engine.  The investment of the kit and two extra quarts of oil (10% of the oil in the engine) typically pays for itself within months of the first year.  Then the reduced maintenance cost is pure profit for your bottom line. Normal fleet maintenance is roughly 7% of your revenue.  Would a Bypass System drop that to 4% every year you’re in business?  Could you add thousands or tens-of-thousands in profit to your business so easily?

Diesel Fuel System

Your semi-truck diesel fuel system is pretty bulletproof from the manufacturer.  The key is staying up on basic maintenance and keeping the right additives in your diesel fuel.  Keep efficiency high and deposits low.  The fuel injectors on your engine aren’t made for owner adjustment.  Thankfully keeping them flowing well is as easy as adding AMSOIL Diesel Injector Cleaner into the fuel tank when you fill up.  It also helps to lubricate your complete fuel system to reduce fuel pump wear.  It also keeps fuel lines lubricated from drying out and leaking, and can boost your fuel efficiency up to 8%.  Pouring one bottle in could restore your fuel system and reduce deposit buildup.  Add more fuel efficiency to extended oil drain intervals.

Beyond the basic AMSOIL Diesel Injector Cleaner, AMSOIL does have specific products to increase Cetane points, increase cold flow by reducing fuel gelling in colder climates, and additives that combine all properties that you may need to run coast-to-coast. If you need more Cetane, perhaps because you’re running a heavier shipment, pour bottle of AMSOIL Cetane Boost in your fuel tank before your next shipment. Planning to run into the northern states or Canada during winter? Pour in a bottle of AMSOIL Diesel Cold Flow. You may not have a specific route and could go anywhere at any time. If you need the best in every situation, go with the AMSOIL Diesel All in One for your fuel system. It has all additives for the best of all situations no matter the weather, time of year, or load amount.

Chassis Lubrication

With so much talk about the engine, you’d think we forgot how important the transmission is. Not so fast! Thankfully, the transmission is easy to take care of. The question on which AMSOIL product to use comes down to whether you have a manual or automatic transmission in your semi-truck. If you have a manual transmission, you’re going to add AMSOIL SAE 50 Long-Life Synthetic Transmission Oil at your next transmission fluid change. This oil allows drain intervals up to 5 years or 500,000 miles, depending which is going to come first. That could be every four or five years, which makes it a no-brainer to add to your truck. If you have an automatic, no matter what brand or how many gears it has, select AMSOIL Torque-Drive® Synthetic Automatic Transmission Fluid. It offers smoother shifts, smooth engagement, and reduce internal wear for your transmission in any climate you’re hauling through.

Other chassis areas to consider are your differential which also can be put on the infrequent but crucial list for fluid changes. Add AMSOIL Synthetic Gear Oil to your differential and increase your replacement time to 5 years or 500,000 miles similar to your automatic or manual transmission.

You can also grease your 5th wheel mount with AMSOIL Synthetic Fifth-Wheel Grease to keep trailers going on and coming off smooth with minimal wear to the attaching plate. The rest of the chassis can be well lubricated with AMSOIL Synthetic Greases in polymeric or multi-purpose varieties.

Keeping your diesel semi-truck in great shape for years to come can sound like a daunting task. The truth is that it’s pretty easy with dedicated routine maintenance, and adding AMSOIL products from Buy Great Oil is also the best way to reduce your maintenance cost for your trucking fleet. If you’re unsure about which AMSOIL product is best for your semi-truck, feel free to drop us a line. We can help with the products that best fit your requirements because we are your local best local AMSOIL dealer.

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