Vortec 8.1L 6-Speed Conversion Kit

Name: Vortec 8.1L 6-Speed Conversion Kit
Brand: DuraMax Tuner
SKU: D06C DM13AJ090080900
Price: 2147.27 USD
Availability: InStock

$2,147.27

SKU: D06C DM13AJ090080900

In Stock

Ships by Jun 7

Free Shipping

Non-Returnable Item

DIY PRO SHOP

Moderate — 2–4 hours

Description

This kit upgrades 2001-2005 GM 8.1L Vortec Silverado/Sierra trucks with an Allison 5-speed transmission to a 6-speed. It includes custom calibrations for improved shift quality and firmness. Benefits include a 14% RPM reduction (approx. 300 RPM lower at highway speeds), leading to improved highway fuel economy, a quieter cabin, reduced engine wear, and extended engine life.

Fitment

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

Brand	DuraMax Tuner
Part Number	D06C DM13AJ090080900

Videos

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Allison 5 to 6 speed conversion

I CAN'T BELIEVE THIS DURAMAX 6 SPEED CONVERSION MADE THIS MUCH OF A DIFFERENCE!!

We Install!

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Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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