FLEECE FPE-CLNTBYPS-CUMMINS-0607 CUMMINS COOLANT BYPASS KIT 2006-2007 AUTO TRANS

Cure rear-cylinder hot spots and stabilize cooling on your 2006–2007 5.9L Cummins automatic with the FLEECE FPE-CLNTBYPS-CUMMINS-0607. This proven kit improves coolant flow at the back of the block to help reduce peak temps, prevent pressure spikes, and protect freeze plugs during towing, performance use, and daily driving. Fleece 5.9 Cummins coolant bypass 2006 2007, rear cylinder cooling fix, freeze plug protection, Allison grade control not applicable, plug and play coolant bypass, CPP Diesel Fleece

Why this kit

• Targets the rear of the block where coolant flow is weakest
• Helps reduce coolant temps and pressure spikes under load
• OE-quality fittings, clean routing, reliable long-term solution
• Designed and supported by Fleece Performance Engineering

Fitment

Engine: 5.9L Cummins (common-rail)
Model years: 2006–2007
Vehicles: Dodge Ram 2500/3500 equipped with 5.9L Cummins
Transmission: Automatic transmission only (see Cross-Reference for manual and other years)

Cross-Reference / Related Fleece Items (CPP Diesel)

• FLEECE FPE-CLNTBYPS-CUMMINS-0607-SS — 2006–2007 Auto (Stainless Line)
• FLEECE FPE-CLNTBYPS-CUMMINS-MAN — 2003–2007 Manual
• FLEECE FPE-CLNTBYPS-CUMMINS-MAN-SS — 2003–2007 Manual (Stainless Line)
• FLEECE FPE-CLNT-HS-BRKT — 2003–2007 Coolant Bypass Brackets
• FLEECE FPE-CLNTBYPS-CUMMINS-0712 — 2007.5–2012 6.7L
• FLEECE FPE-CLNTBYPS-CUMMINS-1318 — 2013–2018 6.7L
• FLEECE FPE-CLNTBYPS-CUMMINS-19 — 2019–Present 6.7L

Rear cylinders on the 5.9L Cummins see less coolant flow and the highest temps. This kit adds a bypass path to equalize flow and reduce localized overheating and pressure spikes.

Yes. The kit uses quality hoses and fittings and can be removed if desired. No permanent engine modifications are required.

On 2003–2007 automatic applications, the bypass configuration eliminates the OE coolant-to-trans heat exchanger, which is primarily useful in very cold climates.

No tuning changes are required. This is a mechanical cooling system upgrade.

California Proposition 65 warning applies; see the Specifications table below for details.

Specifications for FLEECE FPE-CLNTBYPS-CUMMINS-0607