The Stovebolt Site Forums The Shop Area Paint and Body Shop 41/42 Rear Window installation woes

I have a 42 3/4 ton with what appears to be a 40/41 cab rear window. The frame around the opening has holes and there is a metal frame that goes over it. The rubber I got only has a notch on one side. How does it install? :confused:

You may have the wrong rubber, I'd check with whomever you got that from and see if they stock the 40-41 gasket.

mine is actually a metal frame that holds the rubber in place from the outside. There is no locking rubber or strip. Holes need to go through the rubber around the glass and then screws go through from inside the cab. The only grove in the rubber fits the glass. There is a slight taper to the rubber and I wonder if that goes toward the cab or away. I did check and it is the correct rubber. I got one for a 42 first and it doesnt fit at all

On my '41 the heavy rubber seal has a grove around the inside where it slips over the window glass. There are holes through the rubber seal for the bolts that hold the assembly together.

The window frame is on the outside of the cab. On my truck this frame is a zink (pot metal) die-casting. The frame has small bosses for the threads for each of the bolts

The heads of the bolts are inside the cab and the bolts pass through the cab's inside trim, then the cab itself, then the heavy rubber seal, and finally thread into the widow frame clamping the whole thing together.

My original gasket was in poor shape so I ordered one. The new one came with the correct holes for the bolts BUT did not have counter bored (enlarged) holes on the outside face to accept the thread bosses on the die-cast window frame. I could not make this rubber seal fit and had to send it back. I ended up cleaning up my original.

I have been told that there are two different window frames, one is die-cast like mine, and one is stamped steel. I have not seen a steel one but wonder if it has the same thread bosses. If not I'll bet my purchased gasket was meant for the steel one.

P.S. If you have the die-cast frame be VERY careful with it. They are not very strong and do not like to be bent or bowed.

You might have to mark & drill the mounting holes thru the rubber gasket - mine came with no holes.

Thanks all for the info. I will have to drill holes and countersink the rubber as well I guess. Does the slightly tapered side go toward the cab or out and do you need to put any sealer on the rubber?

I’m afraid I can’t be much help here, as I can’t remember which was the “slightly tapered side”. I do know that I did not use any sealer and it does not leak, but then it spends all its time in the garage. Hopefully another bolter can help.

" Rounded " edge goes toward window frame. When I did mine, laid out glass on a piece of 3/4" plywood, fit rubber around the glass, drove nails around the outside perimeter to hold the shape and cut to length. Rubbed a light coat of grease on the face of the rubber and set potmetal frame on top - hole locations show on the grease. Drilled and countersunk for the holes. Siliconed the glass into the gasket, set the frame on top, and had a friend hold in place while I screwed from inside.