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How do I properly Maintain my 1st Gen 12V Cummins Pickup Truck?

If you’re reading this, it probably means you’re the proud owner of a 1989-1993 Dodge Ram D/W pickup truck. These trucks are the first generation of Dodge Ram Pickups available with a diesel engine. The diesel engine in these trucks is no ordinary engine however, they’re one of the most durable diesel engines ever built. Just because they have a reputation for durability, doesn’t mean that you should take a chance when it comes to proper maintenance though. With how easy it is to work on these trucks, there is no excuse for not taking care of one. I’ll cut you some slack though, it’s not easy finding the right parts and your truck might not have come with an owner’s manual. Don’t worry about it. You’ve come to the right place! We make taking care of your truck easy with our comprehensive 1st Generation 5.9L Cummins Maintenance guide.

Our 1st Gen 5.9L 12V maintenance guide gives you the proper service schedule to follow and detailed information pertaining to fluid capacities and specifications. We’ll even give you the exact parts you’ll need and links to where you can find them on Amazon. Assuming you have the parts you need at your home, you won’t have to go the store to pick anything up. All you need is a little bit of mechanical know-how and be willing to learn. If you need to learn a little bit before hand, spend a little time on Youtube. Changing fluids and filters is very easy, even for a beginner mechanic or a DIYer.

When Should I Service My Truck?

If you just bought your 12V Cummins, I would strongly recommend giving it a maintenance overhaul immediately. You don’t know how it was treated in the past. They could’ve worked the truck really hard or used it for work. If it’s a previous fleet vehicle, it probably wasn’t serviced as frequently as it should be. You also don’t know if the previous owner or the dealer you just bought it from used the proper fluids, filters, or engine oil. Don’t take the unnecessary risk! Just go ahead and service the truck as soon as you can.

If you’ve owned the truck for a while, maybe you’re just unsure of if you’ve been following the proper service schedule. Take a look at the mileage of your truck, and see where you’re at in comparison to the chart below. I recommend changing fluids every year or couple of years. Don’t be afraid of performing maintenance sooner than the mileage requirement. Fluids, oil, and parts can lose quality and degrade over time too. It’s better to perform maintenance too soon than being too late. Always keep in mind, the better you treat your truck, the better she will treat you.

What is the Correct 1st Generation 5.9L Cummins Service Schedule?

Follow the 1st Generation 5.9L Cummins maintenance schedule below like your life depends on it. Just remember, there are other parts that could fail that might need to be replaced too. Check out our section about things you should do every oil change to make sure you can catch problems like front end and steering problems early.

Normal Operating Conditions Service Schedule

Severe Operating Conditions Service Schedule

The following chart is the 1st Generation Cummins Maintenance schedule to follow if you frequently tow, idle, or drive in city conditions. If you use your truck for work, or if you beat on your truck, this is the First Gen Cummins service schedule for you.

1st Generation Cummins Fluid Capacity

Another important factor in first generation Cummins maintenance is fluid capacity. You want to make sure you know how much fluid or oil you need to purchase before servicing your truck. The last thing you want to do is drain your truck of fluid or oil, only to find out you didn’t buy enough to properly re-fill your truck. Take a look at our 1st Gen 5.9L Cummins Fluid Capacity chart below.

1st Gen Cummins Maintenance Parts

Using high quality parts, filters, and fluids is so important in proper 1st Generation Cummins Maintenance. Finding the best parts and fluids to use is difficult because the 1st gen Cummins is old. To make it easy on our readers and fellow diesel lovers, we compiled a list of the most common first gen Cummins maintenance parts. Take a look at the chart below. Click on the links below if you’d like to purchase the parts from Amazon! The prices are great and the shipping is awesome for Amazon Prime members.

Learn More About the First Generation Cummins

Click on one of the links below to view some of our other first generation Dodge Cummins diesel resources.

• 1st Gen 5.9L Cummins Specs
• 7 Most Common First Gen 5.9L Cummins Problems
• Best 1st Generation Cummins Upgrades