3 Tips to Get Better Air Flow in Your Kenworth Truck

The following is a guest post thanks to Jon Lewis of Shoreline Truck Parts:

Kenworth trucks are notorious for poor air flow. There’s nothing worse than going down the road
sweating, or freezing. Both of these scenarios can be avoided. In this article, I’ll be sharing 3
tips to ensure that you get the most air flow from your Kenworth truck.
The first thing to consider is the problem may not be your blower motor, but your HVAC box
itself. Having holes in an HVAC box is like trying to pour water into a bucket that is filled with
holes. Your bucket will quickly fail at it’s job. The same goes for your blower motor.

1 - Inspect Your HVAC BOX

Inspect your Kenworth HVAC box for corrosion, holes, and air gaps. First, run the AC/heat and
feel around your box for air leaks. If you find major corrosion, you may want to consider
replacing your Kenworth heater box with a stainless steel version. If your KW truck has a metal
HVAC box and spends much time in northern states that salt their roads, there’s a good chance
that your truck is seeing signs of corrosion. If the corrosion is bad enough, it will eventually wear
a hole in your box.

Second, all Kenworth HVAC manufactures use gasket material in various locations on the

boxes to prevent air leaks. The areas most prone to leaks are around the top cover and the area

where the evaporator line come out of the HVAC box. Adding gasket material to these areas

can help stop the air leaks. Thirdly, check the venting behind the dash in your truck. Many

models of Kenworths have vent tubing similar to dryer vent hoses. Over time, the venting tube

easily cracks.

2 - Clean Heater Core and Evaporator

Example of a clogged heater core

If your box is in good shape, another cause for bad air flow is a dirty/clogged evaporator and

heater core. This is especially common for trucks that run a lot on dirt roads or dusty work sites.

Dust mixed with condensation in your HVAC box will create a wall of debris making your

evaporator and heater core impenetrable. Heater cores and evaporators should be cleaned

every one to two years.

3 - Upgrade Your Blower Motor

The last thing to check, if you have found that your box is in good shape, the evaporator and

heater core are clean and it doesn’t have any air leaks, consider replacing your OEM blower

motor with an upgraded blower motor. Our company, Shoreline Truck Parts, offers a Blower

Motor Upgrade Kit that will give you a 15% increase in CFM. Our upgrade kit includes a

stainless steel lid and baffle plate, the upgraded blower motor, and gaskets.