Gen 5 V8 (LT4, LT1, L83, L86)
Adapter & Extension Harnesses
6L80 / 6L90 / 8L90
6L80/6L90/8L90 Tap Shift Switch Box
Yes [Add $25.00]
For use with Twist MachineShrifter?
Yes [Add $50.00]
Add 8L90 Tap Shift CAN Relay?
Yes [Add $300.00]
Don't want to switch to a custom shifter? That's OK. The 6L80/6L90/8L90 will operate with any shifter. Just add our switch box to allow for tap up/tap down shifting. The switch can be mounted any place that's convenient for you.
Requires E38/T43 reprogramming for proper operation with 6L80/6L90 setups. Not compatible with E67 setups!
8L90 Tap Shift CAN Relay
for TapShift to work on Gen 5 swap using the 8L90 transmission.
Add pigtail? Select "Yes" if you're not using a Speartech powertrain harness with the Tap Shift plug built into the harness.
Pigtail is not necessary when using the tap shift switch box with an 8L90 transmission. Our 8L90 Tap Shift CAN Relay includes everything needed.
If using this for a Twist Machines Shrifter, you must select "Yes" to "For use with Twist Machines Shrifter" You do not need to select Yes to Add Pigtail!
If you don't have a Speartech harness with the TapShift plug on it, please see
for wiring info (6L80/6L90 only).
6L80 / 6L90 / 8L90 Gear Indicator
GM LS-Series Engines: The Complete Swap Manual By Joseph Potak
Speartech Air Intake Kit
Sale Price: $24.99
Truck to Vette ETC Pedal Adapter
6L80/6L90/8L90 AN Transmission Cooler Manifold
Cable-X Speedometer Adapter
6L80 / 6L90 Reverse Light CAN Relay Kit
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