SKU: DMTDM1361070080900

Allison Transmission 6 Speed Conversion Kit

Ships From Manufacturer in 3-5 Days
Confirm fitment before purchasing
YEARS
2001-2005
MAKE / MODEL
GM/Chevrolet/GMC / Silverado/Sierra
SERIES
2500HD/3500HD
ENGINE
6.6L Duramax LB7/6.6L Duramax LLY
Price
$1,999
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PRODUCT DETAIL

Key Features & Description

Features:
  • Custom TCM tuning for your specific truck
  • Double Overdrive = 14% RPM reduction
  • All new valve body, wiring harness, and solenoids
  • Lowered road noise
  • Gear indicator works on Edge CTS monitor
  • Works with high idle, retrofit tap shifters
Enhance multiple aspects of your ride with the Duramaxtuner 6 Speed conversion kit! 

Take your '01-'05 Allison to another level by adding a sixth gear!

Improve your LB7 or LLY's reliability by utilizing our in-house designed and tested kit coupled with our established transmission tuning. We calibrate firmness and timing of shifts, so you’ll be guaranteed to feel the smoothness and better shift quality missing on the 5 speed Allison. If you’re like the rest of us here at Duramaxtuner using our trucks as daily drivers, the added gear helps take the wear and tear off your engine while cruising at high speeds. It keeps your RPMs at the most efficient curve of the rev range, giving it the best ride possible!

In addition to helping keep your truck on the road longer, something you will notice is the added bump in fuel economy. This is especially true for those of us logging long commutes via highway. Fewer RPMs, the better your fuel economy. Picking up just a little bit goes a long way while putting on the commuting miles. You’ll also notice how much quieter your ride will be when adding our kit to your truck. NVH (Noise, vibration, and harshness) will decrease drastically, giving you a much more enjoyable ride. 

FITMENT GUIDE

Exact Fitment — Verify Your Year

Year RangesYears
Make
Model
Series
Engine
2001-2005
GM/Chevrolet/GMC
Silverado/Sierra
2500HD/3500HD
6.6L Duramax LB7/6.6L Duramax LLY

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