Product Description

Background:  In 2001 thru 2005, all Allison 1000 equipped vehicles, including motorhomes, have 6-speed capability, but the existing transmission control module (TCM) software limits to 5 speed.  The 6th gear is disabled.  With higher gear ratios, the resulting high rpms are fuel wasting.  Optimum cruise rpm is 1800.  This replacement module gives you back 6-speed function.  NOTE: A valve body modification is also required, we do not supply that.

Your existing TCM will be replaced with our custom reprogrammed factory module.  We use tested A-grade TCM’s equivalent to what is in your truck (NEW units are available as an upgrade).  You will observe a 350 rpm reduction resulting in:

• A 2-3 MPG CRUISE ECONOMY IMPROVEMENT,
• QUIETER.  REDUCED ENGINE NOISE EMMISSIONS,
• INCREASED ENGINE LONGEVITY,
• INCREASED OIL CHANGE INTERVALS,

There are two programming options:

FACTORY SHIFT PACKAGE: A stock experience from GM engineering.

or

CUSTOM REFINED SHIFT PACKAGE: A number of improvements from the factory shift schedule. You should notice less 6^th gear engagement during high throttle, lower speed operation (hills and headwinds). This is intentional, intended to reduce gear shifting (hunting) between 4^th, 5^th and 6^th gears, especially useful with larger tires. You should also note that the truck is less “jerky” during unloaded and “in-town” driving, due to changes made to torque converter lockup.

IMPORTANT:  LB7, LLY, 2001 to 2005 YEAR AND VIN CODE “1” or “2” (8^th DIGIT IS “1” or “2”.)  Your VIN will be required, kindly provide it with your module, or contact us separately.  We can also supply a VIN for custom non-factory projects.  Ship your module to us, or local drop off service also available.

This is a TCM exchange-only program.  Since we cannot program your TCM, a refundable TCM swap fee will be automatically added to your cart in checkout, return shipping instructions included.  Contact us if you elect to send in your TCM in advance and avoid this charge.