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How Oil Consumption Affects Your Turbo Diesel’s Exhaust System

How Oil Consumption Affects Your Turbo Diesel’s Exhaust System

Ever wonder why engines have that long wiry thing with the small plastic handle? A.K.A. the dipstick?

“Come on, Mark, it’s for measuring proper engine oil volume,” you say.

Sure, but here’s the million-dollar question: How often should you pull the dipstick and check your oil level?

Survey the masses and you’ll find that most people only touch the dipstick after they change oil to verify the oil level. Shame on you, masses. Don’t you care about your engine? Continue reading to find out why checking oil frequently is important to protecting your engine.

All engines burn oil

Yes, they do, whether you realize it or not. It’s a natural function of lubricating the piston ring/cylinder liner interface. The rings must seal against the liner for the engine to build compression. Compression builds the horsepower we all love so much. Without that oil film, we’d turn the key, back the truck out of the garage and – BANG! – there goes your engine. Some of the oil film, however, burns with every piston stroke.

Ask yourself again: why do engine’s have a dipstick?

Is it really just to verify the proper oil level after an oil change? Or should we be checking oil more frequently as part of our daily driving routine?

Now that we know all engines burn some oil, we should ask ourselves how long it has been since we lasted checked oil. Pop the hood and pull the dipstick to ensure the engine oil level resides in the safe area on the dipstick. Top-off as needed lest you become that unfortunate person who spills coffee on himself when the engine goes BANG while backing out of the garage.

So, where is the oil going?

Maybe you’re wondering what happens to the oil that burns in the combustion chamber.

If you own a diesel pickup built in or after 2007, listen up.

The oil burns and is pushed into the exhaust stream, just like the byproducts of burned diesel fuel.

All 2007-and-newer trucks are equipped with a diesel particulate filter (DPF). If your truck was built in or after 2010, it has a selective catalytic reduction (SCR) system. These two devices manage the byproducts of diesel combustion and reduce emissions.

How does a DPF work?

The DPF collects and separates the partially burned byproducts of diesel fuel, similar to how an air filter separates and removes airborne dirt particles from the air. These particles collect in the filter until they begin to restrict airflow. At that time the engine reacts and dumps fuel into the exhaust stream to raise the exhaust-gas temperature and help burn the soot byproducts. The system effectively reduces emissions and is built into nearly every diesel application these days.

Example of a diesel particulate filter.

What happens to the burned engine oil as it enters the exhaust stream?

Unfortunately the burned byproducts of engine oil lodge in the DPF and remain there forever. Alternatively, you can remove the DPF for cleaning or replacement.

The problem with oil consumption in diesels is that it can prematurely plug the DPF, rendering it useless.

So, let’s reiterate: all engines burn oil, which can plug the DPF.

That’s the reality with today’s technology. That’s another reason why it’s important to pull the dipstick on a regular basis and track your oil consumption.

The other unfortunate part is that you can do very little to affect how much oil your engine burns. Design tolerances and engine manufacturing affect oil consumption the most.

Your choice of engine oil can make a difference, though

All is not lost, however. Some engine oils offer better protection against oil consumption than others. AMSOIL synthetic diesel oils, for example, have low rates of volatility (burn-off), reducing oil consumption. AMSOIL Signature Series Max-Duty Synthetic Diesel Oil provides up to 76 percent less oil consumption than required by the API CK-4 standard in the Caterpillar-1N oil consumption test. AMSOIL synthetic diesel oils are formulated to protect not only your engine but your exhaust after-treatment system.

So, if you are a diesel burner like myself, your choice of engine oil is important. Choose AMSOIL synthetic diesel oil and start protecting your exhaust system.

At the very least, check your oil on a regular basis to ensure the appropriate level.


Top 5 Tips for Protecting Your Diesel

Top 5 Tips for Protecting Your Diesel

If you love your diesel pickup as much as I love mine, then you know what it takes to make it look good, run good and sound good. It’s no task for the weary or lazy, however. I literally spend hours each week on my truck. It’s a way for me to escape the rigors of life and enjoy time listening to music, enjoying a frosty beverage and doing something I enjoy, whether it’s to make the truck look pristine, change the fluids or replace worn parts in the never-ending quest for better performance.

Whether you love performing your own maintenance or hire it out, here are a few tips, in no particular order, to help keep your diesel running strong.

Protect Your Fuel System

Modern diesel engines have the best fuel-delivery systems available. A pump delivers fuel to a common rail, where the intricate, high-performance injectors take over, spraying it at incredibly high pressures into the cylinder. When operating correctly, this system helps your truck rip down the road almost as quietly as your neighbor’s gasoline car. Take care of the fuel system and it’ll deliver years of excellent performance. Don’t, and you’ll spend thousands of dollars and look foolish stranded on the side of the road.

How do you do it, you ask? A preventative-maintenance program that prescribes diesel fuel additives with every tank of ultra-low-sulfur diesel (ULSD). I use our Diesel Injector Clean and Diesel Cetane Boost every time I fill up. I’m giving my fuel system the detergents it needs to remain clean and operating like new, the lubricity the pump and injectors need to prevent premature failure and, thanks to the boost of cetane, maximum combustion efficiency to gain me the best possible torque and mpg. These two products are the key to fuel system longevity.

Rotate Those Tires

Your truck likely weighs more than 7,000 lbs. No lightweight, by any means. You’re likely running E-rated tires to help carry that extra load, but even those tires take some serious abuse every day. Since your truck carries most of its weight on the steer tires, it’s important to rotate the steer tires and drive tires frequently.

Diesel injectors require regular lubrication in the form of a fuel additive to last as designed.

How often? I rotate mine every 5,000 miles. That schedule gives me plenty of opportunity to check the brakes and suspension components while I’m under there. And, if you’re like me, you have a heavy right foot and you often test your tires’ friction capability in relation to the road surface. That certainly is a recipe for fun, but it’s also a recipe for disaster in terms of more frequent tire replacement. If you’ve replaced the shoes on your truck recently, you know the tire manufacturers aren’t giving them away, so rotate them periodically to help extend their life.

Give your baby a bath

I live up in the northwoods where the winters are long and the summers – well, sometimes they rarely come. Those long winters are abusive on our trucks because our state invests heavily in road salt. I often wonder if the plow driver laughs at us guys who try and keep our vehicles clean in the winter. Keeping your truck clean and free of salt is the most important thing to keeping your body panels where they belong. If you plan on keeping your truck for a while, you might want to take this point to heart. Whether you live in my neck of the woods or where it never snows a day out of the year, washing your truck is the best way to protect the paint and keep it looking bright and shiny. A healthy does of wax once or twice a year is also key for fending off the sun’s harmful rays. 

Change your fluids

Most people know they need an oil change every so often. They likely have a method of keeping track and change oil religiously, like every spring and fall. But, do you ever put any time into the transmission? How about the differentials? How about the coolant or brake fluid?

Your truck’s life and performance depend on the lubricants and fluids it requires. And no fluid lasts forever, so if someone tells you otherwise, call BS. You pay good money for your truck, and lots of it, too, if you just bought a new one. Each component needs a fluid change every so often to flush any contaminants that may have accumulated and replace degraded fluids. Use synthetic fluids to help promote performance and longevity for your truck. Synthetics’ longer service life also gives you the opportunity to extend service intervals, reducing the number of times you have to crawl under the truck.

Extra filtration

Diesel and soot go hand in hand. It’s a fact of life, folks. Your diesel’s combustion efficiency isn’t 100 percent, so it generates soot. Where the soot ends up is a function of the engine and its operating conditions. The exhaust system properly manages most of it, but some soot makes its way into the sump, contaminating your engine oil. Soot in small quantities and small particles is no match for the dispersants in your engine oil. The problem comes from larger quantities that stress the dispersant system until it fails, allowing larger particles to form that cause abrasive wear to your engine and form deposits that reduce engine efficiency.

Want a fool-proof way to manage soot in your engine? Use high-quality AMSOIL synthetic diesel oil and add a bypass filtration system. The oil will keep soot particles in suspension and the filtration system will remove them from the oil. Our bypass systems are capable of removing much smaller particles than the normal full-flow oil filter, which is why it’s so important to a diesel engine. Your truck is worth it. The cost to add a bypass system is minimal with respect to the love you have for your truck.

By now, I hope you picked up at least one tidbit of value to help keep your baby looking good and lasting a long time. I know with the effort I put into my truck, I’ll be driving it well into the 200,000-mile range. Some of you think that is nothing and expect a diesel to last longer. I have no doubt it will, but I’ll probably get bored by then and will want the next greatest diesel thing. Heck, maybe by the time I replace this one, we’ll have half-ton diesel pickups with as much torque as my current truck, but with fuel economy in the 40+ mpg range. Or, maybe the truck will be able to drive itself. Don’t laugh – do a little research online and you’ll find over-the-road trucks doing it today.

Either way, this outta tell you how long I plan to keep my current truck. But the only way our trucks will last for year is to show them some love.