W900L AC issues, will not push air out very hard.

My ‘93L will not blow hard at all. The 3 speed selector works on all 3 speeds but will not blow hard. Air is cool but could stand to be colder. Last year I replaced the compressor, drier and expansion valve. It operated ok but has never been good or close to great. Considering buying a new aftermarket box that contains the blower, evaporator and heater core. Might this help?

 

The evaporator is likely plugged with dirt. Just needs a cleaning

 

I'm about to buy this myself...

 

Worth it, did one truck already, have 2nd to do it on. buy the full kit with new cores and get a matched set of expansion valves seperately though, replace bunk ac valve at same time.

Only real headache i had on that was their freeze switch, doesnt really make a whole lot of sense where and how they have it set up to go in the core.

Only other advice i have, drilling the studs out from the engine side may be easier and less frustrating than trying to get the nuts off from the cab side and the way it bolts up instead of having a welded stud on the new box will probably require a 2nd set of hands for a few minutes

 

Replace the whole box. They rot out.

 

they make a stainless steel replacement box complete, that is cheaper then the oem box

 

Never seen a blower motor last much past a year or so on a KW without a filter. For being a brand on the high end of the spectrum they sure cheaped out on having a cab filter. Dust just eats those blower motors up.

 

I found a complete box, from Shoreline Manufacturing.

 

Thats the one, impressive shipping imo as well, ordered on their site, was at my house 2 days later 500 miles away

 

Make sure the squirrel cage blowers are on the right way. I have
seen quite a few put on backwards when the blower motor was replaced.
The air volume is probably around 20% when they are installed backwards.