Diesel Truck Maintenance
May 17, 2022

Diesel Truck Maintenance – A Guide to Extend the Life of Your Truck

Written By: ProSource Diesel

It’s important for any vehicle to be properly maintained if you want to maximize its lifespan and reliability.

However, taking care of a diesel truck has its own unique requirements compared to gas trucks. Certain maintenance tasks for diesel trucks must be performed on a regular basis or you will significantly shorten the life of your engine.

Note: capacities vary greatly so it is a good idea to research what you have and how much fluid you’ll need. You can typically find this information online or in your owner’s manual.

Let’s take a look at some crucial engine maintenance for your diesel truck.

Engine Oil

Diesel trucks are different from gas trucks in that they have larger oiling systems that let them go longer between changes. In fact, the oil change frequency for diesel trucks is largely dependent on the exact make and model of your vehicle as well as how you use it.

For example, the 6.0L Powerstroke is very susceptible to oil contamination and should have its oil changed every 3,000 to 5,000 miles.

Newer common-rail diesel engines that burn a lot cleaner can often extend oil life to 7,000 or 10,000 miles.

*Note* – The engine oil we provide is in compliance with the requirements of the manufacturer’s OE specs and approvals.

  • Powerstroke 7.3L 6.0L 6.4L 6.7L (Approvals: CJ-4)
  • Cummins 5.9L 6.7L (Approvals: CF-4/CG-4/CH-4/CI-4/CJ-4)
  • Duramax 6.6L LB7 LLY LBZ LMM LML L5P (Approvals: CH-4/CI-4/CJ-4/CK-4)

Here’s the common schedule for some popular diesel engines:

Maintenance Schedule Interval Maintenance Supplies Available
1989-1993 5.9L 12V Cummins every 5,000 miles 1989-1993 5.9 Cummins Oil Change Kits
1989-1993 5.9 Cummins Oil Additives
1994-1998 5.9L 12V Cummins every 5,000 miles 1994-1998 5.9 Cummins Oil Change Kits
1994-1998 5.9 Cummins Oil Additives
1998.5-2002 5.9L 24V Cummins every 5,000 miles 1998.5-2002 5.9 Cummins Oil Change Kits
1998.5-2002 5.9 Cummins Oil Additives
2003-2004 5.9L 24V Cummins every 5,000 miles 2003-2004 5.9 Cummins Oil Change Kits
2003-2004 5.9 Cummins Oil Additives
2004.5-2007 5.9L 24V Cummins every 5,000 miles 2004.5-2007 5.9 Cummins Oil Change Kits
2004.5-2007 5.9 Cummins Oil Additives
2007.5-2012 6.7L 24V Cummins every 7,500 miles 2007.5-2012 6.7 Cummins Oil Change Kits
2007.5-2012 6.7 Cummins Oil Additives
2013-2022 6.7L 24V Cummins every 7,500 miles 2013-2022 6.7 Cummins Oil Change Kits
2013-2022 6.7 Cummins Oil Additives
6.6L Duramax LB7 every 5,000 to 7,500 miles 6.6 Duramax LB7 Oil Change Kits
6.6 Duramax LB7 Oil Additives
6.6L Duramax LLY every 5,000 to 7,500 miles 6.6 Duramax LLY Oil Change Kits
6.6 Duramax LLY Oil Additives
6.6L Duramax LBZ every 5,000 to 7,500 miles 6.6 Duramax LBZ Oil Change Kits
6.6 Duramax LBZ Oil Additives
6.6L Duramax LMM every 5,000 to 7,500 miles 6.6 Duramax LMM Oil Change Kits
6.6 Duramax LMM Oil Additives
6.6L Duramax LML every 5,000 to 7,500 miles 6.6 Duramax LML Oil Change Kits
6.6 Duramax LML Oil Additives
6.6L Duramax L5P every 5,000 to 7,500 miles 6.6 Duramax L5P Oil Change Kits
6.6 Duramax L5P Oil Additives
7.3L Powerstroke every 5,000 miles for normal use and 3,000 miles for severe use 7.3 Powerstroke Oil Change Kits
7.3 Powerstroke Oil Additives
6.0L Powerstroke every 7,500 miles for normal use and 5,000 miles for severe use 6.0 Powerstroke Oil Change Kits
6.0 Powerstroke Oil Additives
6.4L Powerstroke 10,000 miles for normal use and 5,000 miles or 200 hours for severe use 6.4 Powerstroke Oil Change Kits
6.4 Powerstroke Oil Additives
6.7L Powerstroke every 10,000 miles or as indicated by the Intelligent Oil Life Monitor system 6.7 Powerstroke Oil Change Kits
6.7 Powerstroke Oil Additives

Gear Oil

Gear oil is an oft-forgotten part of diesel maintenance. It’s one of the most neglected fluids simply because it’s rarely changed in lighter-duty vehicles. However, diesel trucks typically do a lot of heavy work.

Gear oil should thus be changed every 20,000 miles of heavy towing. It should be changed about every 50,000 miles of mixed-use driving.

*Note* – The gear oil we provide is in compliance with the requirements of the manufacturer’s OE specs and approvals.

However, this can vary by the engine as follows:

Maintenance Schedule Interval Maintenance Supplies Available
1989-1993 5.9L 12V Cummins every 15,000 miles 1989-1993 5.9 Cummins Differential Service Kit
1994-1998 5.9L 12V Cummins every 15,000 miles 1994-1998 5.9 Cummins Differential Service Kit
1998.5-2002 5.9L 24V Cummins every 15,000 miles 1998.5-2002 5.9 Cummins Differential Service Kit
2003-2004 5.9L 24V Cummins every 15,000 miles 2003-2004 5.9 Cummins Differential Service Kit
2004.5-2007 5.9L 24V Cummins every 15,000 miles 2004.5-2007 5.9 Cummins Differential Service Kit
2007.5-2012 6.7L 24V Cummins every 15,000 miles 2007.5-2012 6.7 Cummins Differential Service Kit
2013-2022 6.7L 24V Cummins every 15,000 miles 2013-2022 6.7 Cummins Differential Service Kit
6.6L Duramax LB7 every 50,000 miles 6.6 Duramax LB7 Differential Service Kit
6.6L Duramax LLY every 50,000 miles 6.6 Duramax LLY Differential Service Kit
6.6L Duramax LBZ every 50,000 miles 6.6 Duramax LBZ Differential Service Kit
6.6L Duramax LMM every 50,000 miles 6.6 Duramax LMM Differential Service Kit
6.6L Duramax LML every 50,000 miles 6.6 Duramax LML Differential Service Kit
6.6L Duramax L5P every 50,000 miles 6.6 Duramax L5P Differential Service Kit
7.3L Powerstroke every 100,000 miles normal use and 30,000 miles for severe use 7.3 Powerstroke Differential Service Kit
6.0L Powerstroke every 97,500 miles 6.0 Powerstroke Differential Service Kit
6.4L Powerstroke every 50,000 miles for severe use, but otherwise only if there’s a leak 6.4 Powerstroke Differential Service Kit
6.7L Powerstroke every 150,000 miles under normal conditions 50,000 miles under severe duty conditions 6.7 Powerstroke Differential Service Kit

 

Vehicles with 6.7L Cummins were equipped with various differential options from LSD (limited slip differential) to non-LSD, tall ratio to short ratio etc. All these units work very hard in a heavy truck that is destined for even harder use.

There were many variations that a vehicle could be ordered with, good news is that we have every fluid available to service nearly every single differential.

Coolant

Modern diesel engines run quite hot thanks to exhaust gas recirculation, which is an emissions requirement. EGR is very hard on coolant, so it’s essential to keep a regular eye on your coolant to make sure that it is still protecting your engine.

The following flush intervals are recommended for specific engines:

Maintenance Schedule Interval Maintenance Supplies Available
1989-1993 5.9L 12V Cummins every 24,000 miles 1989-1993 5.9 Cummins Coolant
1994-1998 5.9L 12V Cummins every 24,000 miles 1994-1998 5.9 Cummins Coolant
1998.5-2002 5.9L 24V Cummins every 24,000 miles 1998.5-2002 5.9 Cummins Coolant
2003-2004 5.9L 24V Cummins every 24,000 miles 2003-2004 5.9 Cummins Coolant
2004.5-2007 5.9L 24V Cummins every 24,000 miles 2004.5-2007 5.9 Cummins Coolant
2007.5-2012 6.7L 24V Cummins every 100,000 miles or 60 months 2007.5-2012 6.7 Cummins Coolant
2013-2022 6.7L 24V Cummins every 100,000 miles or 60 months 2013-2022 6.7 Cummins Coolant
6.6L Duramax LB7 every 150,000 miles 6.6 Duramax LB7 Coolant
6.6L Duramax LLY every 150,000 miles 6.6 Duramax LLY Coolant
6.6L Duramax LBZ every 150,000 miles 6.6 Duramax LBZ Coolant
6.6L Duramax LMM every 150,000 miles 6.6 Duramax LMM Coolant
6.6L Duramax LML every 150,000 miles 6.6 Duramax LML Coolant
6.6L Duramax L5P every 150,000 miles 6.6 Duramax L5P Coolant
7.3L Powerstroke every 15,000 miles 7.3 Powerstroke Coolant
6.0L Powerstroke every 45,000 miles 6.0 Powerstroke Coolant
6.4L Powerstroke every 50,000 miles 6.4 Powerstroke Coolant
6.7L Powerstroke every 45,000 miles 6.7 Powerstroke Coolant

Transmission Fluid

Transmission fluid has seen a lot of advancements just like other fluids, which means that change intervals are longer than before. However, diesel enthusiasts almost never leave their engines stock, so the horsepower gains will reduce transmission fluid life.

*Note* – The transmission oil we provide is in compliance with the requirements of the manufacturer’s OE specs and approvals.

The following are some transmission fluid change intervals for different engines:

Maintenance Schedule Interval Maintenance Supplies Available
1989-1993 5.9L 12V Cummins every 24,000 miles 1989-1993 5.9 Cummins Transmission Fluid Kit
1994-1998 5.9L 12V Cummins every 24,000 miles 1994-1998 5.9 Cummins Transmission Fluid Kit
1994-1998 5.9 Cummins Transfer Case Fluid
1998.5-2002 5.9L 24V Cummins every 24,000 miles 1998.5-2002 5.9 Cummins Transmission Fluid Kit
1998.5-2002 5.9 Cummins Transfer Case Fluid
2003-2004 5.9L 24V Cummins every 24,000 miles 2003-2004 5.9 Cummins Transmission Fluid Kit
2003-2004 5.9 Cummins Transfer Case Fluid
2004.5-2007 5.9L 24V Cummins every 24,000 miles 2004.5-2007 5.9 Cummins Transmission Fluid Kit
2004.5-2007 5.9 Cummins Transfer Case Fluid
2007.5-2012 6.7L 24V Cummins every 120,000 miles for normal use and 60,000 miles for severe use 2007.5-2012 6.7 Cummins Transmission Fluid Kit
2007.5-2012 6.7 Cummins Transfer Case Fluid
2013-2022 6.7L 24V Cummins every 120,000 miles for normal use and 60,000 miles for severe use 2013-2022 6.7 Cummins Transmission Fluid Kit
6.6L Duramax LB7 every 50,000 miles for normal use and 25,000 miles for severe use 6.6 Duramax LB7 Transmission Fluid Kit
6.6L Duramax LLY every 50,000 miles for normal use and 25,000 miles for severe use 6.6 Duramax LLY Transmission Fluid Kit
6.6 Duramax LLY Transfer Case Fluid
6.6L Duramax LBZ every 50,000 miles for normal use and 25,000 miles for severe use 6.6 Duramax LBZ Transmission Fluid Kit
6.6 Duramax LBZ Transfer Case Fluid
6.6L Duramax LMM every 50,000 miles for normal use and 25,000 miles for severe use 6.6 Duramax LMM Transmission Fluid Kit
6.6 Duramax LMM Transfer Case Fluid
6.6L Duramax LML every 50,000 miles for normal use and 25,000 miles for severe use 6.6 Duramax LML Transmission Fluid Kit
6.6 Duramax LML Transfer Case Fluid
6.6L Duramax L5P every 50,000 miles for normal use and 25,000 miles for severe use 6.6 Duramax L5P Transmission Fluid Kit
6.6 Duramax L5P Transfer Case Fluid
7.3L Powerstroke every 21,000 miles 7.3 Powerstroke Transmission Fluid Kit
7.3 Powerstroke Transfer Case Fluid
6.0L Powerstroke every 30,000 miles 6.0 Powerstroke Transmission Fluid Kit
6.0 Powerstroke Transfer Case Fluid
6.4L Powerstroke every 30,000 miles 6.4 Powerstroke Transmission Fluid Kit
6.4 Powerstroke Transfer Case Fluid
6.7L Powerstroke every 150,000 miles 6.7 Powerstroke Transmission Fluid Kit
6.7 Powerstroke Transfer Case Fluid

Fuel and Fuel Filter

You might be wondering why fuel is included here with the fuel filter. In some cases, you might have to drain your tank and refuel. Moisture in diesel fuel is very bad for the engine, and it can get in when you least expect it.

A good rule of thumb is to always use a high-traffic gas station to get a good batch of gas. Fuel that sits too long underground can accumulate moisture.

If these intervals seem a lot shorter than gas engines, they definitely are. Diesel engine fuel filters get dirty a lot faster.

For fuel filters, consider the following intervals:

Maintenance Schedule Interval Maintenance Supplies Available
1989-1993 5.9L 12V Cummins every 15,000 miles 1989-1993 5.9 Cummins Fuel Filters
1989-1993 5.9 Cummins Fuel Additives
1994-1998 5.9L 12V Cummins every 15,000 miles 1994-1998 5.9 Cummins Fuel Filters
1994-1998 5.9 Cummins Fuel Additives
1998.5-2002 5.9L 24V Cummins every 15,000 miles 1998.5-2002 5.9 Cummins Fuel Filters
1998.5-2002 5.9 Cummins Fuel Additives
2003-2004 5.9L 24V Cummins every 15,000 miles 2003-2004 5.9 Cummins Fuel Filters
2003-2004 5.9 Cummins Fuel Additives
2004.5-2007 5.9L 24V Cummins every 15,000 miles 2004.5-2007 5.9 Cummins Fuel Filters
2004.5-2007 5.9 Cummins Fuel Additives
2007.5-2012 6.7L 24V Cummins every 15,000 miles 2007.5-2012 6.7 Cummins Fuel Filters
2007.5-2012 6.7 Cummins Fuel Additives
2013-2022 6.7L 24V Cummins every 15,000 miles 2013-2022 6.7 Cummins Fuel Filters
2013-2022 6.7 Cummins Fuel Additives
6.6L Duramax LB7 every 15,000 miles 6.6 Duramax LB7 Fuel Filters
6.6 Duramax LB7 Fuel Additives
6.6L Duramax LLY every 15,000 miles 6.6 Duramax LLY Fuel Filters
6.6 Duramax LLY Fuel Additives
6.6L Duramax LBZ every 15,000 miles 6.6 Duramax LBZ Fuel Filters
6.6 Duramax LBZ Fuel Additives
6.6L Duramax LMM every 15,000 miles 6.6 Duramax LMM Fuel Filters
6.6 Duramax LMM Fuel Additives
6.6L Duramax LML every 15,000 miles 6.6 Duramax LML Fuel Filters
6.6 Duramax LML Fuel Additives
6.6L Duramax L5P every 15,000 miles 6.6 Duramax L5P Fuel Filters
6.6 Duramax L5P Fuel Additives
7.3L Powerstroke every 15,000 miles 7.3 Powerstroke Fuel Filters
7.3 Powerstroke Fuel Additives
6.0L Powerstroke every 10,000 miles 6.0 Powerstroke Fuel Filters
6.0 Powerstroke Fuel Additives
6.4L Powerstroke every 10,000 miles 6.4 Powerstroke Fuel Filters
6.4 Powerstroke Fuel Additives
6.7L Powerstroke every 22,500 miles or as indicated by the intelligent monitor 6.7 Powerstroke Fuel Filters
6.7 Powerstroke Fuel Additives

Brake Fluid

Brake fluid degrades over time due to its hygroscopic quality, which means that it easily attracts moisture like a sponge. If there’s moisture in your brake fluid, that means that the boiling point will be lowered. The heat that goes through your brake system is plenty to boil old brake fluid.

Having degraded brake fluid in your system can be a safety issue, especially if you tow. Check your specific manual for the recommended intervals to flush and replace brake fluid. A common interval is every 24 months.

According to recommended service intervals for Powerstroke, Cummins, and Duramax diesel engines, brake fluid and power steering fluid should be checked during every service and flushed and replaced as necessary.

Shop Supplies

For the DIY mechanic, it’s essential to have a good stock of shop supplies on hand to assist in your maintenance and repair tasks. Some common shop supplies that work for many repair and maintenance applications include the following:

Most of these items are very necessary for many routine maintenance jobs. For example, WD40 can be used to lubricate bolt holes, as a rust inhibitor, and to unstick locks, among other applications. It’s definitely a DIY shop must-have.

Maintaining Other Diesel Truck Parts

Keeping up on your truck’s fluids is a great start to increasing the lifespan of your engine. If you have a 4WD truck, you generally also want to change the transfer case fluid every 60,000 to 100,000 miles.

However, if you don’t use 4WD much, some trucks can definitely go much longer. It’s a good idea to perform a maintenance check every 10,000 miles or 12 months, whichever comes sooner.

Your air filters will likely need to be changed at this point. One thing to understand about diesel trucks is that diesel fuel is a dirty-burning fuel.

Checking up on your engine regularly is mainly to make sure that it’s staying clean. If you can keep your engine as clean as possible, you will increase its life expectancy significantly.

Signs You Need Maintenance

Hopefully, with regular maintenance, you won’t run into any of these problems very often. However, diesel parts can also fail unexpectedly. Here are a few trouble signs to keep an eye out for:

  • Weak acceleration
  • Decreased power
  • Sputtering engine
  • Stalling unexpectedly
  • Strong vibrations
  • Fluid leaks
  • Excess exhaust smoke
  • Steam or strange smells from the engine
  • Unusual engine noises

Rely on ProSource Diesel to repair or replace your diesel engine parts, including Cummins parts, Duramax parts, and Powerstroke parts. We sell a wide selection of aftermarket and OEM parts to keep your diesel engine running great for a long time.

Leave a Comment





Shopping Cart
0