This video shows an install on a 1999 Kenworth W900L Shout out to Fine Line Transport in Holland, MI for helping us film this video.

The unit that we are installing is our K142-535ss-3 plug & play system. The OEM cross-reference for this unit is K142-535-1. This unit will fit a 1995 – 2002 Kenworth W900, T800, T600, T400, and T450.  To find the plug & play unit specific to your year and model truck, visit our Kenworth HVAC box page.

The K142-535ss-3 includes all the parts needed to install the HVAC box on your truck. The following parts are included:

Step 1 – Begin evacuating the AC.

Evacuate AC

Step 2 – Remove the air intake ducting.

Remove Air Intake Ducting

Step 3 – Turn off valves for the coolant lines on the passenger side of the motor.

Shut off Valve

Step 4 – Use a pair of pliers to remove the coolant hoses from the heater core. Have a bucket ready.

Remove coolant hoses

Step 5 – Remove the plastic cover (3) 10mm fasteners.

Remove plastic cover

Step 6 – Use a T25 Torx bit to remove the reinforcement bracket.

Remove bracket

Step 7 – Use a 10mm socket to remove the (4) fasteners from the lid. Remove the lid.

Remove lid

Step 8 – Unhook the blower motor and discard the lid.

Unhook blower motor

Step 9 – In order to remove the airline from the air actuator/air cylinder, press down on the white plastic collar and pull out the plastic tube.

Remove air line

Step 10 – Use a 10 mm wrench and socket to remove the AC lines from the AC bracket.

Remove AC Bracket

Step 11 – Grind off the top two bolts that hold the HVAC box to the firewall.

Grind top two bolts

Step 12 – Use a 7/8 wrench to remove the lower AC line.

Remove lower ac line

Step 13 – Use a 5/8 wrench to remove the upper AC line. Remove any other accessories attached to the box.

Remove upper ac line

Step 14 – Use a T20 Torx head to remove the three screws from the glove box.

Remove glove box

Step 15 – Use a 13mm socket to remove the (3) fasteners inside the cabin of the truck. After popping off the circled cap, pop the other cap out of the socket extension.

Remove 3 fasteners

Step 15B 

Fastener behind two plugs

Step 15C 


Step 16 – Use a pry bar to help remove the HVAC box from the firewall. Then remove the box.

Remove HVAC box with pry bar

Step 17 – Clean up the surface for the new box.

Clean up surface for new box

Step 18 – Prepare the new shoreline box for installation.

Prepare Shoreline box for install

Step 19 – Remove the lid by taking out the four bolts using 10mm socket.

Remove lid

Step 20 – Unhook the blower motor from the wiring harness.

Unhook blower motor

Step 21 – Remove the 3 screws from the blower motor.

Remove 3 screws from blower motor

Step 22 – Begin to install the box.

Remove blower start install of of box

Step 23 – This HVAC has a rubber grommet installed in the box. Your truck has rubber grommet installed in the firewall as well. It is easier to slip the wiring harness through the grommet when the grommet is removed from the truck than it is to try to push your wiring harness through the grommet. So we would encourage you to pull that grommet out. This is where the grommet is located and pull that grommet out. Slip the wire through the grommet and then install onto the firewall.

Rubber Grommet

Step 24 – Use a 13mm shallow socket and rachet with 13mm deep socket to snug the top 2 bolts of the heater box of the firewall. Don’t tighten it down all the way yet.

Top two bolts

Step 25 – Begin installing the (3) fasteners inside the cab of the truck. Don’t tighten them all the way down as the wiring harness in the air line needs to be squared away first before buttoning everything up.

Begin installing fasteners

Step 26 – Reinstall AC lines

Reinstall AC Lines

Step 27 – Use a T20 Torx head to remove the (2) screws from the dash panel.

Remove dash

Step 28 – Remove dash

Install and tighten down bolts and nuts

Step 29 – Unplug the old wiring harness and plug in the new wiring harness. Remove the old wiring harness.

Unplug wiring harness

Step 30 – Remove the (4) T20 Torx screws from the AC control to access the old air line. The old air line is connected between this button and the actuator or air cylinder in the HVAC box.

Remove AC control

Step 31 – Remove the old air line and plug in the new air line.

This is the air line that returns back to the HVAC box, press down on the white collar to remove the old line and then replace it with a new one.

Remove Air line and plug in new air line

Step 32A – Start putting the dash back together. 

Start putting the dash back together

Step 32B – Dash


Step 32C – Glove box

Glove box

Step 33 – Finish tightening down these (3) fasteners completely.

Finish tightening down fasteners

Step 34 – Install the reinforcement bracket at the front of the truck.

Install Reinforcement bracket

Step 35 – Finish tightening down the top (2) bolts.

Finish tightening down top two bolts

Step 36A – Install the blower motor.

Install blower motor

Step 36B – The wiring harness has a black wire and a blue wire with a black stripe. The blue wire with a black stripe is hot and the black wire is ground. Make sure the ground in the truck is connected to the ground on the blower motor. If these are reversed, the motor will run backwards and will not blow very hard.

Wiring harness instructions

Step 36C – Install blower fasteners. (3) Phillips head fasteners.

Install blower fasteners

Step 37 – Use a 10mm socket to reinstall the (4) bolts for the lid. 

Reinstall Lid

Step 38 – Reinstall air intake ducting

Reinstall air intake ducting

Step 39 – Recharge the AC

Recharge AC

Step 40 – During AC season, the coolant valves can remain off. Otherwise, if you need heat, open these valves back up.

Turn on valves
My cart
🎁 Only $50.00 away from free shipping to
Your cart is empty.

Looks like you haven't made a choice yet.