ALLISON 04-05 LLY 6 SPEED CONVERSION WITH TCM

Name: ALLISON 04-05 LLY 6 SPEED CONVERSION WITH TCM
Brand: Sun Coast Converters
SKU: S02K A1-6VB-TCM-LLY
Price: 2950.00 USD
Availability: InStock

$2,950.00

SKU: S02K A1-6VB-TCM-LLY

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Moderate — 2–4 hours

Description

The Sun Coast A1-6VB-TCM-LLY Allison 5-6 Speed Conversion for your 2004.5-2005 GM 6.6L Duramax LB7 converts your 5-Speed Allison A1000 Transmission into a 6-Speed like the later models. With the conversion, you can drop 325 engine rpm @ 75 mph with 3.73 gears, while increasing fuel economy 1-1.5 MPG, and reducing engine noise while cruising. The gear ratio in your 5 speed is .71 and our 6th gear will be .61. Requires valve body and TCM change. No wiring, no modifications required.

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Specifications

Brand	Sun Coast Converters
Part Number	S02K A1-6VB-TCM-LLY

Videos

Duramax 2001 - 2005 Six Speed Conversion

Less Road Noise, Better Fuel Economy? The 6 Speed Conversion Kit Is What Your LB7 Or LLY Needs!

Allison 5 to 6 speed conversion

We Need An Extra Gear - DIY 'Till I Die Ep. 4

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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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