Project DeadSpool: Building A 2,500-Horsepower Proven Transmission

As you all already know, our diesel drag truck project, Project DeadSpool, has been in full force throughout the 2018 season. Well, with the all-new addition to the Outlaw Diesel Super Series – the Firepunk Diesel Outlaw 5.90 Index class – we are going to need some upgrades. It takes a ton of power to commute down the drag strip in under six seconds, and that means we’re going to need a drivetrain that will handle that big power.

What we have been running for over two years now is a Firepunk Diesel Comp 2 48 four-speed transmission backed by a Diesel Performance Converters triple disc torque converter. While this transmission was plenty for what we were doing, we wanted the extra insurance heading into the 2019 race season.

As you all know, Project DeadSpool is a 2005 Dodge Ram powered by a 5.9-liter Cummins backed by a 48RE transmission. The 48REs have their share of problems, so we turned to Firepunk Diesel for help.

So, what are we changing up and what is it capable of? Well, the next step above the Comp 2 transmission from Firepunk is their Comp 3 transmission. This is the same build that Firepunk’s Lavon Miller and colleague Matt Kauffman used in winning first and second place in the 2014 Diesel Power Challenge in Denver, Colorado. It’s clear that these transmissions can take the abuse and keep on truckin’.

As you can see, this kit comes with everything you will need to rebuild your transmission, and the Firepunk team has them readily available to ship. Not included in the kit is the “fat shaft” input shaft or the billet stator support.

We are upgrading our Comp 2 with some parts from a Comp 3, including a Diesel Performance Converters quad disc torque converter, a fat shaft input shaft, and a heavy-duty rebuild kit from Firepunk. We are moving from the stock size input shaft to the larger diameter “fat shaft,” simply because they are so much stronger. Also, we’re rebuilding the unit since we’ve put two years of abuse on it and want it to be fresh for the upcoming season, and now we’re using a quad disc torque converter for the additional horsepower and torque we plan to feed it.

The Firepunk Comp 3 utilizes oversized shafts. This makes the transmission capable of handling extreme horsepower and torque. With this one removed, we now have room for our fat shaft input.

Instead of palleting up our transmission and shipping it up to Plain City for Firepunk to tear into it, Miller was nice enough to let us build it ourselves. Luckily for us, our friends Paul Cato and Grant Anderson over at Maverick Diesel are less than an hour away and they have the experience we need to get this 48RE refreshed and race ready for the 2019 season.

By removing the transmission pan, this exposed all of the hardware to remove the parking rod and the valve body. To get all of the internals out for cleaning and replacement, this is your first step. Although these guys have done this enough to make it look easy, it was definitely a confidence test as to whether or not it’s doable at home. But the truth is, without knowing the clearances and tolerances of the moving parts, it’s best to have a professional do it.

There are OE selective snap-rings and thrust washers that transmission shops have on the shelf to get the clearances perfect during a rebuild. When you’re doing it at home, you could be left waiting on parts if the clearances don’t add up correctly.

After we drained the remaining fluid out of the transmission, you could see its blood run out. Although, if you have ever seen transmission fluid out of a truck with this much abuse, this fluid looks phenomenal. One thing to certainly keep in mind is when you upgrade and buy one of these rebuild kits, it comes with the new pan gasket. As you can see, we struggled to get the pan off because instead of buying a new gasket years ago, I used RTV and basically made cement. "You could have probably taken all of the bolts out of this pan and raced without leaks," said Cato.

Features:

  • Built For High Horsepower Applications 1000HP+
  • Two-year Unlimited Mileage, 100% Workmanship Warranty (Workmanship Warranty follows the transmission builder)

Build List:

  • Fat Shaft Billet HD Input Shaft
  • Maraging Billet Intermediate Shaft
  • Fat Shaft Billet Output Shaft
  • Custom Billet DPC Heavy Duty Triple disc converter (Lifetime Warranty)
  • Competition Master Kit (includes added clutches in Direct drum and in OD Brake. OD direct clutch modification and oversized HD 2nd gear band)
  • Billet Double Seal 2nd Gear Servo
  • Billet Strut
  • Billet Anchor
  • Billet Accumulator Piston
  • Billet 4.2 Ratio Apply lever
  • Firepunk Built High-Pressure Valve Body
  • Deep Pan with drain plug + temp sender port
  • Billet SFI 29.3 Approved Flexplate

Note: The transfer case input shaft must be changed to fit the oversized shaft

We are stoked to know that our transmission is built right and by one of the best in the business. It has been said that these transmissions will take 2,500 horsepower when maintained correctly. How does that sound? We can’t thank the guys over at Maverick Diesel for the installation of this rebuild enough. If you’re looking to upgrade your truck, be sure and check out their website. Big thank you to the crew at Firepunk Diesel for hooking us up with the parts to rebuild our transmission. We can’t wait to put it to the test. Stay tuned to Diesel Army for more soon.

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About the author

Artie Maupin

Artie Maupin is from Southeast Missouri and has an extreme passion for anything diesel. He loves drag racing of all kinds, as well as sled pulling competitions.
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