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Diesel Truck Parts And Accessories

2020 Chevy/GMC 6.6L L5P Duramax

The release of the 2020 model year Chevrolet and GMC pickups brought about a lot of debate mostly surrounding the huge facelift they received, most notably the Chevrolet models. But, lets face it, nea ... read more

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The release of the 2020 model year Chevrolet and GMC pickups brought about a lot of debate mostly surrounding the huge facelift they received, most notably the Chevrolet models. But, lets face it, nearly every single vehicle upon initial release has had its naysayers, so is this really any different? Overall, whether you like the aesthetics or not, GM came guns a-blazing in the powertrain department for 2020 so without further ado, lets dive into what's new!

Probably the most sought after upgrade was to the much familiar Allison 6 speed automatic transmission. While continuing with the Allison branding (which we'll dive into in a minute), the tried and true six speed has been ditched in favor of a ten speed. That's right folks, you'll need all ten fingers to count as you roll through the gears now. Why 10? Why not! Having access to double digit gears will allow for less abruptness when under load between gear changes, meaning your turbo stays in its peak powerband, keeping power flowing smoothly, temperatures at a minimum, fuel economy at its maximum, and less wear and tear on parts. Sounds like pretty good reasoning, huh? Now for the oddity. While the truck will bear the "Allison" markings, this transmission was only initially designed and tested by Allison, but will actually be built by GM.

For the real part of why you're here, the L5P Duramax engine, yes, its still rated at the previous power figures of 445 horsepower and 910 foot pounds of torque (and it puts all of those 910 to the ground in 1st gear!), there were some substantial changes that allow for a huge max towing capacity increase. Model year 2019 had GM's max towing capacity lingering at a 23,100 capacity, which, honestly, was behind the pack, but for 2020, hits a homerun with 35,500 pounds! There were numerous upgrades made to allow for this increase, but any pertinent are related to ensuring cool operating temperatures. For instance, there's a new, 2.5" larger diameter fan that is spun by an independent drive belt ran off of a secondary pulley on the front of the damper. Also, this Duramax has a substantially larger oil cooler that will aid in keeping those temps down when you're actually yarding around 35k pounds.

Now, for those of us in cooler climates, there's a larger block heater in the engine which is accompanied by a relocated block heater cord in the bumper. Why in the world has it taken so long for the OEM's to actually give us a spot for the block heater that didn't require it dragging across our front bumper or crawling under it? Well, either way, nicely done. Another cool upgrade that was borrowed from the aftermarket is an integrated cool down timer. In the event that your temps are nearing the red zone and you're headed for a pitstop, your dash will deliver a light indicating that a cool down is necessary to allow for continued coolant circulation and the fan to run. If you decide to ignore this light, don't be alarmed, but the truck has the ability to literally restart itself and run for up to 15 minutes or until a safe shut down temperature has been reached.

Overall, while this truck still bears "L5P" engine designation, a LOT has changed. In fact, from an exterior standpoint, the only piece of sheetmetal shared by its predecessor is that of the roof. We think GM really did their homework with this truck in what everyone has been asking for.

We get a lot of calls and e-mails each day with various product, vehicle, and installation questions. Some are completely off the wall and can even catch us off guard at times, but many others are fairly routine, so we thought we'd post some of the most popular questions that can hopefully be a good resource for you.

Q: I have an EFILive AutoCal for my earlier Duramax. Can that same tuner work on my L5P Duramax?
A: In short, no, EFILive has not yet updated their files to allow L5P tuning to be loaded into their AutoCal tuning devices.

Q: Will a DPF (Diesel Particulate Filter) back system provide more sound to my truck?
A: Generally speaking no, the emissions equipment upstream will still act as a muffler. However, that doesn't mean installation will not help in other areas by improving exhaust flow. While minor, the benefits are noticeable, plus an aftermarket exhaust looks way better than the stock exhaust.

Q: I'm looking at an exhaust kit on your website, but it doesn't state which cab and bed configuration it fits, will this fit my application?
A: In most cases, unless it is specifically stated as fitting a certain configuration, all exhaust kits on our website will fit all cab and bed lengths. Further, most kits will not fit cab and chassis applications unless otherwise noted.

Q: I'm looking at this 5" (or other) exhaust kit, but my truck only has a 4" exhaust now. Does this 5" exhaust include an adapter / reducer?
A: Yes, the exhaust systems we sell will adapt down to fit the application at the designated starting point (turbo back, cat back, DPF back, etc.) for a hassle free installation.

Q: What are EGT's?
A: EGT stands for Exhaust Gas Temperature, which is the temperature of the exhaust leaving your engine. This measurement is typically measured before the turbo to ensure you are not overheating components. For most applications, we recommend not exceeding 1300 degrees.

Q: Will the products you offer void my warranty?
A: Some parts may void your warranty and some may not. We recommend researching the Magnuson-Moss Warranty Act that specifically protects consumers when choosing to install aftermarket components on their vehicles, as well as consulting with your local dealer.

If you've got a question about your Duramax, feel free to give us a call at 888-99-DIESEL and we would be happy to assist.

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