Flex Technologies CAC40-350X6 Hot Side Charge Air Boot | 3.5" ID x 6" | Aramid

Premium aftermarket hot-side charge air cooler boot from Flex Technologies, a US silicone hose manufacturer in Gardena, California. Aramid-reinforced silicone rated to 500 F for the turbo-to-cooler run, with stainless steel retention rings moulded in. Flex is ISO 9001:2015 and IATF 16949:2016 registered.

Signs You Need a New Charge Air Boot

• Boost leak with noticeable power loss and poor throttle response
• Audible whistle or chuff at the joint under load
• Boot blows off under high boost, often after the clamp relaxes
• Silicone gone soft or swollen from turbo seal oil seepage
• Cracking or ply separation at the clamp bead
• Check engine light for boost pressure deviation or turbo underboost

Specifications

Cross References

This part replaces or is equivalent to the following part numbers:

• Flex Technologies: CAC40350X6
• TruckPro: NFCAC40-350X6

Applications

This boot is a universal cut-to-fit charge air connector, sold by inner diameter and length rather than by truck model. It fits the hot-side run from the turbocharger compressor outlet to the charge air cooler inlet on Class 6-8 trucks, where air temperatures routinely reach 300-450 F under load.

Do not substitute a blue CAC40P polyester boot on the hot side - polyester tops out at 350 F and fails early there. Measure the pipe OD and the gap between pipes before ordering.