I was wonder if anyone on this forum has water coming in there peterbilt 387 when it rains? I want to the dealer and ask them and they told me it comes in from the blower box sometimes because of leaves clogging the drain holes. but I have clean them and it still seems to get in when it rains hard. It's mostly under the carpet..

Thanks in advance

I know of one 387 that has the same problem and the dealer told them the same thing they told you and it didn't solve the problem.

I had the same thing with a 387 I had a guy driving. Two things to try.
1) take out or fold back the carpet. Get a can of spray undercoating (from ant auto store) and spray all seams and joints.
2) make sure the AC drain line is connected and free/open as the AC works all the time and when it is draining condensation if the line is blocked the tray overflows.
Don't know which one worked for me as we did them both at once but the problem went away.

How did u get to the Ac drain line? I think I would like to try and fix that first ..

thanks

Easiest to do it is thru the passenger door (remember this was the way we did it, might not be the way in the Pete book )
Up under the dash, under the glove box, is a big black "lump". Track down all the screws that hold it in place. After getting them all undone wrestle it out of place. You will end up with a few little pieces of plastic left over (that broke off) at the end but it will still fit back tight. Oh, and if you bleed easaly have some band aids handy. You will see the AC/Heat blower down tube (the blower is actualy outside near the right hand wiper) but you will see it come down. Look where it goes into a "box", under that box will be a flat looking tray, that is the drip pan. On the right front corner you can track down a 3/8 clear plastic tube that runs down to a hole right where the firewall joins the floor.
Tip :- If you don't wana spend an hour or so cleaning the inside of the cab find a way to blow down it not up. We tracked it down outside and blew up, was that ever a mistake :sad: :sad:
Hope this helps.

Thanks i will try and fix this when i'm home again.. I thought I fix the problem by making more holes in the drain pocket under the windshield wiper blades and still water is getting in but it mostly under the rug..

thanks again

Nope, it is down in the "cooling" area not in the blower area (Up top)