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Summers End Flex Savings! Take $15 off any in-stock Flex Fuel Kit.

2008-2014 Chevrolet Silverado/Sierra Lethal Garage Flex Fuel Kit - Coming Soon

Regular price $289.99

Unit price per 

only 0 left in stock

Our custom E85 Flex Fuel kit for the 2008-2014 Chevrolet Silverado & GMC Sierra with a 4.8L, 5.3L, 6.0L (HD Models) or 6.2L engine, is just what you need for more power, savings on fuel costs, and a better smelling ride... (Okay that last one is subjective). This kit is assembled by Lethal Garage and it includes the following:

  • 1 - GM OEM Flex Fuel Sensor
  • 1 - GM OEM Fuel Line 
  • 1 - Gen5DIY Custom Plug & Play Power Harness
  • Two Year Warranty on all GM parts as provided by GM & lifetime warranty on the Gen5DIY harness that covers any defects in craftsmanship.  

Our product is designed to tuck away and be hidden allowing 100% concealment if your hood is popped. 

Vehicle Fitment:

  • 2008-2014 Chevrolet Silverado 1500 models with the 4,8L, 5.3L or 6.2L engine
  • 2008-2014 Chevrolet Silverado HD Models with the 6.0L engine


  • This kits harness uses OEM connectors in tandem with OEM products. Fit and finish look 100% stock under your vehicle. Your truck will pick up 10-15rwhp on e78 or better depending on the tune.
  • Note: While the GM flex fuel sensor can be installed and works perfectly fine to run pump gas with your vehicle without a tune, to run E85 your truck must have a tune to run E85 fuel. DO NOT INSTALL & RUN E85 WITHOUT A PROPER TUNE. Make sure your tuner has verified your sensor is hooked up and reading the ethanol content before adding e85 to your vehicle.

Install Guide: 

~Coming Soon~


WARNING California Residents - cancer (and/or reproductive harm) -

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