Therefore it is not necessary to bleed the coolant circuit completely after removing and installing the auxiliary heater or the circulation pump -V55-. However, if a large quantity of coolant has escaped due to another problem, e.g. a leaking hose, or after coolant pipes have been renewed, the coolant circuit must be bled → Rep. gr.19. Product Details. Increase coolant flow to the rear heater in your 2000-01 truck with Auxiliary Heater Coolant Fittings. These fittings have an improved design which removes the factory designed restriction. Fittings also work in 2002-12 trucks as a replacement for original pieces which are prone to leaking. Fittings are located under the hood. I cut the heater core outlet hose at the engine. I attached the heater outlet hose to the engine side using the supplied ⅝ - ¾" hose splicer. This will allow for the heater to circulate the hot coolant through the engine first before the heater core. I then attached the heater inlet hose to the heater core side of the hose above the EGR cooler. Advanced diesel-fired coolant heater for engines The Proheat X30 is an advanced diesel-fired coolant heater for engine preheat, cab and fluid heating in cold weather climates. The system features O2 feedback that adjusts to the environment, allowing the heater to operate more efficiently regardless of altitude, weather or fuel type. Buy Heater Hoses(5.0L P AJ133 DOHC CDA S/C Enhanced, Electric Auxiliary Coolant Pump, parts for the Land Rover Range Rover Sport (2014+) [3.0 I6 Turbo Diesel AJ20D6]. 7am EST - 5pm PST 888-527-9396.