Best Duramax Upgrades – How to Build an LLY on a Budget the Right Way

All of us here at Diesel Power Products live and breathe diesels.  Its true, ask any of our family members, its actually a disease (in the good way, because its contagious!).  Every once in a while, we like to let you know what we drive ourselves on a daily basis, along with any upgrades that we’ve made to give you a better understanding as to why we recommend them when you call in and happen to have the exact same truck.  

For this particular episode of What Do We Drive, we will be featuring one of our very own sales technicians, Sands Anderson, discussing his 2004.5 Duramax, which we have affectionately dubbed Ron Burgundy.  Take it away, Sands!

“When I started working at Diesel Power Products, I was surrounded by 2nd, 3rd, and 4th Gen Cummins, as well as a couple of Powerstrokes.  So I decided to go a different direction—a Duramax with a manual transmission. Going manual limited my options, but I finally found an ad for an 04. I figured it was a LB7. But when I went to look at it, it turned out to be an LLY. I shook it down, went for a test drive, then bought it that day. When I was cleaning it out, I found a dealership receipt for a new clutch installed two months before I bought it!”

“The first upgrades were basic bolt-ons. I started with an aftermarket 4-inch exhaust from Diamond Eye. This opened things up and let her breathe.  This dropped EGT’s and she was instantly more responsive. Next up, an S&B CAI and a turbo mouthpiece (the factory turbo mouthpiece is known to cause overheating issues because it overworks the turbo). I finished off phase one with a PPEI Tuned EFILive AutoCalFASS Titanium 150gph pump (for better filtration and fuel delivery), a GRP fuel filter delete, tie rod sleeves, and an Edge Insight CTS2 to monitor what the truck was doing. Shortly after that, the newly replaced stock clutch lost its grabbing power, so I hit up South Bend Clutch for a Street Dual Disc rated at 650hp. Then I put down 455hp at the Diesel Power Products dyno event. Clutch issue solved!”

“After a while, I decided I didn’t want to run the VGT charger anymore. Another tech here at DPP runs a Borg Warner SXE369, and his truck got down. So I decided to go for the 369 charger. I collected parts for 8 months. I ended up with an SXE369/73/.91 T4, Fleece T4 Stainless Pedestal, S300 Install Kit, HX40 Downpipe, and Empire Performance Alternate Fire Cam.  For those not familiar with this cam, the last cylinder in the firing order is 3, then it goes 1 and 2, so it get three quick hits right to the front of the crank. This re-distributes the firing order to take stress off of the crank.  After all that, I discovered my factory cam pin was about to shear off. A wiring pin swap at the FICM connector was all it took.”

“Now I was ready for Dynomite Diesel 75hp injectors. I knew I had the extra air to support more fuel. The turbo is fed through PPE Race manifolds and up-pipes. The engine gets its air through Pusher Intake LLY Y-bridge and charge pipe. The heads are held on with ARP head studs and sealed with GM C-Grade gaskets. I upgraded the factory coolant hoses with PPE hoses.”

“After all this work, she likes to party, sounds great, runs really smooth, and has great power. The Edge monitor has recorded 1300 EGT’s, but I’ve never seen it get above 1200 on full kill WOT. I estimate I now have about 600hp going to the rear wheels. Overall, I’m extremely happy.  Now it’s time to work on the outside. I’m going cliché—4.5″ lift 35-12.50-20’s on 20×10 wheels. Then I’m going to color-match the grille, change mirrors, and drive it till the wheels fall off!”

Thanks Sands, we look forwards to the next episode of What Do We Drive, featuring the infamous Ron Burgundy!

To see the video of Sands telling it how it is, CLICK HERE.

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