The newest Duramax L5P engine is still a mystery to some truck owners. It has a slightly different fuel system that includes a lift pump. When a fuel filter monitor shows that it is time for replacement, what do you have to deal with? How many fuel filters on a 2020 Duramax are installed?
The 2020 Duramax still has only one diesel fuel filter. Some upgraded options include a secondary fuel filter that works as an additional filter that blocks most of the water from mixing with the fuel. The L5P does not cope well with any water level in the fuel lines. That is why now, more than ever, owners are switching from stock fuel filters to improved filters with two components.
If you are a new truck owner with an L5P engine or want to learn something new, stay with us. We covered the fuel filter topic from top to bottom, and you will know how to recognize a faulty filter and when you should replace it. Enjoy!
Understanding Duramax Engine Fuel Filter
Diesel is known as a dirty fuel. Many debris and dirt particles can enter the fuel injection lines, wreaking havoc. Also, the filter should block water from entering the system. Contaminates in diesel fuel and fuel mixed with water will impact the overall work of an engine. It will lower its performance and shorten its work life.
That is why the health of the fuel filter is very important. You need to know how often you should change the fuel filter. Also, it is recommended to use high-quality fuels. If you are using your truck in extreme conditions, you should also think about using fuel additives. All these will help your fuel filter work better and longer. And always pay attention to the fuel filter life monitor. It can save your engine.
Types of Fuel Filters On A 2020 Duramax
The stock fuel filter on a 2020 Duramax comes in cartridge style. There are options to replace them with upgraded filters that work on a spin-on canister style. Some manufacturers are offering filters that have two filters – primary and secondary.
Primary
On 2020 Duramax models fuel filter location is easily accessible. It is located on the frame of the rail when looking from the driver’s side. Look for the fuel and DEF tank, and the filter is right in between. It has two seals, one is on the filter, and the second is on the spout. This filter combines a fuel and water filter combo and can filter particles up to 5 microns in size.
Secondary
Some manufacturers monitored bad fuel symptoms and different types of fuel system contamination. Then they came up with a filtering system that has a second component. This type of filter includes a pre-filter that works as a water separator. The other component is the post filter that catches all the debris up to 3 microns in size.
This type of filter also prevents any possible diesel fuel gelling and prolongs the work life of a fuel pump. The HP4 fuel pump is solid and can handle a lot but it is imperfect. With this type of filter, the fuel pump will have a longer work life and better performance. These filters also offer higher fuel flow volume that can lead to an increase in horsepower.
Some of these filters will also demand fuel heater replacement, so be sure for some additional work. Some of them, like the Fleece FPE-L5P-FFBA-20 fuel filter upgrade kit, have different mounting principles. But they will still offer a lot more than the stock filter. And once you do it, you will know that you upgraded your truck properly and that it will work better.
Maintenance and Replacement Schedule
Even if you have an improved two-component filter, the maintenance and replacement intervals must be followed carefully. Every filter has its work life, and it is one of the crucial fuel system components.
How Often To Change Fuel Filters on a 2020 Duramax
If you use stock Duramax filters, the interval should not exceed 10k miles. An upgraded version of the filters offers longer replacement periods. Depending on the manufacturer, it is between 15 and 20k miles. Watch the fuel system messages if you are unsure when you replaced the filter.
How To Replace Fuel Filters in a 2020 Duramax
Replacing a stock fuel filter is an easy task. You will need protective gloves and a 36mm or 1 inch 7/16 socket. Disconnect the battery just to be sure. Prepare some bucket or something else to catch the leftover diesel from the filter. If you have some experience, this process will take you around 15 to 20 minutes.
- Start unscrewing the filter. Once the fuel starts coming out, stop the unscrewing. Let the fuel slowly pour out into the bucket
- Once the fuel came out, finish unscrewing the filter
- Remove the filter from its casing
- Clean the housing from dirt and debris
- Remove the gasket from the housing and install a new one
- The filter has two different sides. The one with the smaller circle goes down in the casing. Push the filter inside until it pops into place
- In the package comes a smaller O ring that needs to be replaced. It is located on the spout where the filter is fixed on the chassis
- Now you can start screwing on the new filter with your hand. Screw it as much as you can, and then finish it with the socket wrench. Keep screwing the filter until the blue gasket is not visible anymore
- Turn on the car and let the system detect the new filter. Sometimes you will need to reset the fuel filter life manually. Check underneath the car for any leaks before you head into traffic.
Issues with Fuel Filters On A 2020 Duramax
If you follow through on the maintenance and replacement intervals, there should not be any problems. Even the stock filters are good and will do their work correctly. But, in some situations, you may have some problems.
Common Fuel Filter Problems on a 2020 Duramax
In some cases, there can be a problem with a fuel filter. A hole in the filter media will result in massive problems with the fuel pump, fuel lines, and fuel injectors. These occasions are rare but still can happen. If your truck is under warranty, it should be covered. Once your truck is not under warranty, we recommend switching to a better type of filter.
Symptoms of Malfunctioning Fuel Filter
If you notice any of these symptoms, check your fuel filter:
- The engine is stalling. You may experience a sudden loss of power, and the truck can even stop
- Rough idling or misfiring. The engine cannot receive enough fuel if the fuel filter is dirty and clogged. That will lead to rough idling and misfiring
- Failure of different fuel system components. This is usually connected to the high-pressure fuel pump. It is susceptible to damage from poor filtration
- Strange noises from the fuel pump. The fuel pump makes a regular humming noise, but if you notice that it sounds different, check the fuel filter
- Problems with starting the car. If you have a hard time starting your car or cannot start at all, the culprit can be a worn fuel filter
Check Out the Telltale Signs of Bad Fuel Filter: Know Your Car :
Tips and Preventive Measures
All newer Duramax trucks have sensors that send you all the needed information. A fuel filter message tells you when you should approximately change the filter. Check it from time to time.
Also, if you notice any of the symptoms mentioned above, check the filter, or contact a mechanic.
FAQs
Where is the fuel filter on a 2020 Duramax diesel
When looking from the driver’s side, it is located on the frame of the rail. There you will find a fuel tank and the DEF tank, and the fuel filter sits between them.
Where is the fuel water separator on a 2020 Duramax
It sits together with the fuel filter.
Do Diesel engines have 2 fuel filters?
It depends on the engine. Some diesel engines have two filters. The first is located between the fuel tank and the engine, and the second is closer to the engine. The first filter cleans the fuel before it comes to the fuel transfer pump, and the second cleans the fuel before it goes into the fuel injectors.
Final Thoughts
A fuel filter is an important part of the fuel system. It blocks water and dirt residue from entering the fuel systems. That way, the fuel pump, and fuel injectors work better and longer. Replacing a fuel filter is not expensive, and the price range is between $30 and $50 for a stock filter.
Pay attention to filter replacement intervals and change them regularly. You can also replace the stock filter with an advanced two-part filter. They filter the particles and water better and will keep the engine running much better. In either case do not forget your fuel filter, because it is working non-stop. Use quality fuel, and all these factors will positively impact your truck’s engine.
