Roof leak in Volvo vn 780

Could be a small crack in the roof, from a tree branch or something hitting it. But doesn't mean thats where its leaking at either. There are brace's molded into the fiberglass that can act as channels for leaks, it could be leaking in from the back of the cab up high from something like a satellite bracket and following the channels or headliner and out, or from a side window up high and following the headliner to where you see it leaking out. Best bet is to try to get up there look for any cracks or holes, if you can't find any, drop the headliner out when its raining, or have someone spray it with a hose and see where its coming in at.

 

Good luck with finding that leak, my 780 has leaked since it was new and 5 years later still can't find where it's leaking in at.

 

It's a real pain in the butt, but sometimes the only way to find a leak is to gut the interior from the upper side windows and up, have someone spray everything down good with a hose and see wheremits coming from.

 

I thought it was coming in through seal on sunroof, sealed that, still leak's, sealed part where top cap joins bottom , just above drivers door, still leak's. It's coming in through the front area above the cubby holes above drivers head. My drivers seat get's soaked from where it's dripping in.

 

I've got a 2012 780. Done the same thing, it would just pour down from above the drivers storage compartments. Found out that Volvo is having problems with the new style upper bunk windows, water comes in and runs down in between the wall/insulation and the outer cab wall. Replaced the window and so far haven't had any issues with leaking since. Also have a good look at the 2 seams that run down either side on the TOP, they sometimes don't get sealed properly from the factory.