For Dodge 03-07 RAM 5.9L Cummins Diesel Engine Manual Coolant Bypass Kit
Friday, September 25th, 2026
For Dodge 03-07 RAM 5.9L Cummins Diesel Engine Manual Coolant Bypass Kit. For 03-07 Dodge Ram Cummins 5.9L Only Manual Transmission! For 07.5-18 Dodge Ram Cummins 6.7L Manual & Automatic Transmissions. Vehicle compatibility charts ar. E for REFERENCE ONLY. Checkproduct type and sizeto match your needs. For the 03-07 5.9L automatic transmission version will eliminate the factory transmission fluid heat exchanger. The heat exchanger is designed for use in cold climates to warm the transmission fluid with the engine coolant. It is not necessary for use in warm climates or high horsepower applications, nor does it detrimentally affect the trucks performance when removed. For model years 07.5-18 6.7L trucks, including both automatic and manual equipped transmissions, factory installed transmission fluid heat exchangers are uncommon. 100% quality assurance tested, more responsive, less expensive, easier to install. Lower coolant temperature at the rear cylinders. Ensure consistent temperatures across all cylinders. Prevent damaging coolant pressure build up. Come with braided hose and AN O-ring fittings to ensure a leak-free installation. Material: made of high quality Aluminum, Metal &Polyester. 1xCoolant Bypass Thermostat Housing and O-ring. 1xThermostat Riser Block and O-ring. 2xCoolant Bypass Hose Fixing Bracket. 2x (M8x1.25, 20mm) Socket Head Cap Screw. 3x (M6x1.00,60mm) Flange Head Bolt. 2x (M12x1.75, 40mm) Flange Head Bolt. (100% Brand New Never Used Or Installed). Drain coolant from radiator. Dislodge the freeze plug out of the rear engine. Clean plug hole surface by scouring pad. Assemble braided hose to thermostat housing. Line up housing to rear hole, push it and bolt it down. Assemble thermostat riser block to the other end of hose with wrench. Put non-O-ringed side of block against the front thermostat. Set stock thermostat on top, 3 bolt to hold them on. Adjust the hose position to fit engine. Install 2 hose fixing brackets or clamps to hold hoseWhy Need a Coolant Bypass? Increased Coolant Flow, Decreased Coolant Temperatures. The rear cylinders on the 5.9/6.7L Cummins suffer from a lack of coolant flow, and therefore, experience the highest coolant temperatures. This can cause excessive pressure to build in the cooling system, especially the rear of the block and blow out freeze plugs externally, or the smaller diameter plugs under the valve cover, leading to a failure. Our coolant bypass kit adds a secondary thermostat, that unlike other brands, works based on temperature instead of excessive pressure. This solves the problem before pressure becomes an issue by ensuring consistent temperatures across all six cylinders. The Coolant Bypass is one of the most important additions you make to improve the reliability and longevity of the Cummins platform. For the long-time holiday, we’ll post the info on our store and reply you automatically via emails. We’ll try our best to help you solve the problem. Your satisfaction is our main concern, so we try ensure your order is perfect in every way. This can be for any of the following reasons. You simply don’t like your item. The wrong item was sent. The order was faulty or damaged. In the result of you wanting to return an item, you have 30 days to do so, in your return please include reason and action you would like to be taken. In the rare case of a faulty item or wrong item received then please get in contact with our customer service team and we will get the problem resolved as quickly as we can.
