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2004½–2007 CHEVY SILVERADO / GMC SIERRA HD · 6.6L DURAMAX LLY & LBZ

LLY & LBZ Duramax upgrades in Tucson: more power that lasts.

These trucks respond well to cooling, fuel and air upgrades. We do them in the right order, cooling first on an LLY, all installed at your location.

  • 310–360 hp605–650 lb-ft stock
  • Variable turboBosch CP3 pump
  • Allison 10005- or 6-speed
  • We come to youTucson & nearby

KNOW YOUR TRUCK

LLY or LBZ? It changes the parts.

The two engines look alike but use different intakes, intercoolers and cooling parts. Your year tells us which parts to bring.

2004½–2005

LLY

  • 310 hp / 605 lb-ft
  • Variable-geometry turbo and EGR
  • Smaller cooling system; known to run hot towing
  • Allison 1000 5-speed
  • VIN 8th digit “2”
2006–2007

LBZ (and late LLY)

  • 360 hp / 650 lb-ft
  • Larger radiator and updated cooling
  • Allison 1000 6-speed
  • No DPF yet
  • 2007 “Classic” body trucks share it

PERFORMANCE UPGRADES

More power that lasts.

These engines make good power, but heat and the Allison are the limits. We add cooling and fuel first, then air and tuning with the transmission in mind. Gains depend on your truck.

Stage 1

Daily driver & light towing

  • Cooling refresh (radiator, fan clutch, thermostats)
  • FASS lift pump
  • Banks Ram-Air intake
  • Gauges for coolant, exhaust temp and transmission temp
  • PPE deep Allison pan

Typical result: cooler temps, steadier fuel and better pulling.

Call nowRequest a quote
Stage 2

Serious towing

  • Everything in Stage 1
  • Mishimoto radiator and intercooler
  • Emissions-legal Edge tuning matched to your transmission
  • Banks Ram-Air differential cover
  • Allison rebuilt with heavy-duty parts

Typical result: strong, steady towing with temperatures under control.

Call nowRequest a quote

UPGRADES BY CATEGORY

Pick a category to see the parts we install.

Tap a tile to see what it does and the parts we install on the LLY & LBZ Duramax. Every truck is different, so call or request a quote for yours.

RELIABILITY FIRST

Known weak points come first.

Before adding power, we make sure the LLY & LBZ Duramax’s known weak points are handled, so the upgrade lasts.

See the weak points →

How mobile service worksTell us your truck and where it is, we diagnose on site, you approve a written estimate, and we fix it where it sits.

See how it works →

Name-brand partsWe install proven brands like Banks, FASS, Mishimoto, Edge, PPE and Bilstein.

See all the brands we install →

OWNER QUESTIONS

LLY & LBZ Duramax performance questions, answered.

Should I tune my LLY?

Fix the cooling first. An LLY that already runs hot will run hotter with more power.

Will more power hurt my Allison?

It can. We match power to the transmission and add cooling, or rebuild it with heavy-duty parts if you want more.

Are your upgrades street legal?

We install emissions-compliant parts and don’t do deletes.

LET’S TALK ABOUT YOUR TRUCK

Call, text or request a quote.

Tell us your year, mileage and what you want done. We’ll recommend the right build, quote it and come to you.

Truck down?Call roadside service520-990-1033