How do you replace a heater core in a 1995 ford f150?
The heater core is difficult to change on the Ford trucks. They
have it buried in the plenum box and you have to remove the
steering wheel, steering column, dash, evacuate the refrigerant
system, drain the radiator, and remove the plenum box to get to the
core. Replacing the core is easy, getting to it is a day's
You need to be sure that the heater core is really the problem
before tackling this job. If you have a pool of coolant on the
floor, you'll have to go after the core. If the problem is lack of
heat, there are some things you need to eliminate before tearing
into the truck. You need to make sure that coolant is flowing
through the core. Check the temperature of the heater hoses going
into the firewall when the engine is cool and see if they warm up
together as the engine warms up. If both hoses get hot at about the
same rate, this is a good indication that coolant is flowing
through the core. You can also remove the hoses and flush the core
with a water hose splice from Home Depot and a water hose. Water
should flow unobstructed through the core.
If it appears that coolant is flowing and you don't have obvious
leaks, the next step is to check the blend door. This door controls
the air flow through the heater core and failure is common on Ford
trucks. When the door breaks, it can block the flow of air through
the core and kill heat and will also have an impact on AC. If the
system seems to work intermittently, it's a good indication that
the door is broken and rattling around randomly blocking or opening
the passage to the core.
For diagnostic information on how to check the operation of the
blend door and a cheap easy fix, check the heatertreater listing on
Ebay or the web site at heatertreater.net. The dealer fix for the
blend door is basically the same procedure for replacing the heater
core, so it will be expensive. The HeaterTreater alternative will
solve the problem at a fraction of the cost and work and is well
within the capability of the average shade tree mechanic.