Allison LLY 6 Speed Conversion


The Sun Coast Allison 5-6 Speed Conversion for your GM 6.6L Duramax LLY 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, reduces engine noise while cruising, a truck with 3.73 gears that normally likes cruising at 62 MPH will now cruise nice at 72 MPH. The gear ratio in your 5 speed is .71 and our 6th gear will be .61. 6th gear can be disabled with your two haul button and 5th canceled with OD off. Requires valve body and TCM change. No wiring, no modifications required.

Converts 5-Speed Automatic To 6-Speed
Decrease Cruising RPM’s
No Wiring, No Modifications Required

Refundable Core Charge: $1,300.00

SKU: A1-6VB-TCM-LB7-1 Categories: ,

Additional information

Weight 30 lbs
Dimensions 12 × 12 × 12 in


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