Top Parts Every GMT800 Duramax Owner Should Consider

Let’s talk GMT800s

It’s undeniable that the GMT-800 chassis has grown in popularity over the last few years, and for good reason. Objectively, the HD variants of these trucks are some of the best buys on the market dollar for dollar. But that’s not to say they’re without their flaws. Maybe you’re looking to modify your first truck, or maybe you’re just looking to keep your truck running smooth for years to come. Either way, here are our top recommendations when it comes to buying parts for your LBZ Duramax. Pro tip: These also apply to LB7 and LLY trucks as well.

FASS Fuel System

When it comes to prolonging the life of your truck, there are few mods that hit as hard as an aftermarket fuel system from the folks at FASS Fuel Systems. Dollar for dollar it’s hard to beat, and FASS has the pedigree to back it up. Your injection system is the lifeline of your diesel engine. Unfortunately, air, water, and debris can all cause premature wear, which, when left unchecked, can cost you thousands of dollars in potential repairs. A FASS Fuel System works to eliminate air and water and filters well below your factory fuel filter’s size, which means that your diesel truck is getting clean, clear diesel fuel every time you turn the key.

Exhaust

The LBZ Duramax has an unmistakable sound, mostly because of the variable geometry turbos they came equipped with. With an aftermarket exhaust, you’re going to get more than just a good exhaust note; you’re also going to experience far less restriction, helping your engine breathe easier and ultimately make more power. There are several options on the market these days that fit great and sound incredible.

Resonator Delete

A small modification, but one that makes quite a difference, is a resonator delete plug that removes the factory resonator box from under the hood of your truck. Not only does this open up the engine bay and give you a cleaner picture of some of the more integral parts of your engine, but it also gives you more turbo noise when you lay on the skinny pedal. There are several great options on the market from companies like PPE, XDP, Fleece, and more.

Air Lift Company Air Springs (w/ Onboard Compressor)

If you’re towing and hauling a lot, there are few mods that will make as big a difference as a set of air springs from Air Lift Company. With over 75 years in the industry, Air Lift Company does more than just talk the talk; it shows you what the walk looks like when it comes to air springs. This is especially helpful if you’re hauling a bigger enclosed trailer or dump trailer that has a lot of tongue weight. Air Lift’s air springs help eliminate leaf spring sag, balancing out your trailer load, and making your truck a lot easier to drive. While you’re at it, opt for the onboard air compressor kit. This allows you to make adjustments to your air pressures no matter where you are.

Banks iDash

Drive these trucks for any amount of time and you’ll quickly learn that the factory gauges are more so a recommendation than a true display. While they can save you in a panic, if you’re towing, hauling, or just want to have a better understanding of what your engine is really doing, we recommend adding an aftermarket monitor. While there are several options on the market, we prefer the iDash from Banks Power. Fitting into a standard 52 mm gauge pod, the Data Monster allows you to read out several dozen different PIDs from your engine’s computer and gives you real information about things like coolant temps, transmission slip, and more. Pair this with an EGT probe, and you’ve got constant monitoring for your truck no matter where you are.

Wheels and Tires

Both a functional and visual modification, a good set of aftermarket wheels and tires can completely change the way your truck looks. While not the most budget-friendly modification on our list, a good set of wheels and tires will pay dividends to both on-road comfort and off-road traction, as well as helping to ensure that your truck stands out in a crowd.

Intake

The factory intake on these trucks is actually very good. It flows well, filters great, and will support quite a bit of power gain before it becomes a limiting factor. It does, however, come with its own limitations, so if you’re looking to replace that factory air box, we recommend you look at a free-flowing intake from a company like HSP Diesel. These intake kits are going to help your engine breathe better, and to be honest, they look dang good!

EFI Live

Perhaps one of the biggest mods you can do to your truck is one that you’ll never see at all: tuning. While there are several options on the market, EFI Live is tried and true. There are multiple tuner options out there, each with their own unique tune files and power levels, so make sure you do your research and find the right tuner for your specific use case. In any regard, adding EFI Live tuning to your truck is going to give you more power, better fuel efficiency, increased responsiveness to things like your OEM turbo brake, and more. All of this adds up to a better driving experience for you, the driver.

While this list is a great start, it’s certainly not a comprehensive list of modifications. With the aftermarket support for these trucks being so vast, it’s hard to boil it down to just a few items. Regardless, we hope this helps out at least a little bit if you’re looking at modifying your diesel truck for the first time this holiday season!