NOTE: Most wiring harnesses are taking 1-2 weeks to process/ship due to a high volume of orders. If you need immediate shipping please call to confirm availability. To ensure your place in line, please place an order as we ship paid orders first before posting back in stock notices. We can refund at any time.
Finally an aftermarket upgrade option for Trailblazers! This TBSS Spal kit includes two high flow 12 inch Spal fans and a custom black powder coated shroud that uses factory mounting points – no drilling or cutting needed! Fits 5.3L and 6.0 Trailblazers/Envoy/GMT360. This conversion eliminates the power robbing stock electro-viscous fan and replaces it with two computer controlled electric fans. Each fan is independently controlled by the PCM.
Spal Fans & Shroud ONLY – Available if you already have one of our electric fan harnesses (made after 2011) and only want to upgrade the fans.
Three Relay Spal Kit – Complete kit with harness that will bring both fans on at half speed for the LOW setting for quieter operation, and both fans on at full blast for HIGH.
Upgrade to HD Fans – Available as of October 2019! While our basic 12″ Spal fan upgrade is a hit, we have an even more heavy duty version of this kit now available with a thicker, stronger 12″ fan. This option is better suited to highly modified set ups (stroker, forced induction, or a hot climate).
The purchase of this kit includes a voucher for a FREE software fan patch – required to control the fans by computer. This conversion has been credited with gains ranging from 12-18 RWHP and fuel economy improvements of around 1 MPG. These fans can be hard on the electrical system, our three wire battery cable upgrade kit (P-070009 & P-070010) is highly recommended.
Now available for rental or purchase – PCM of NC Fan Clutch Wrenches! Simply add to your cart at checkout and save yourself a trip to the auto parts store. Don’t want to keep it? Send it back within 30 days in working condition for a full refund!
Our manual fan switch (link) is also available for purchase with this kit. NOTE: Fan codes P0480, p0481, and p0483 need to be disabled in your tune for the fan switch, and set to NO ERROR REPORTING. We will do this for free if you send in your ECM.