Rear Window size question

[Chris64]

I'm looking to replace my rear window for a 1974 K-20. It has a slider. I don't know if it's factory. I wanted to change it to a solid window.

Everywhere I look it's called a "large" window. They approx. the glass size to be 16"x64". The problem is that is beyond the size of the outer edge of the rubber by about 1/4". I would expect the glass to be about 15" x 63" or smaller.

When I look for the small window, it's really small. 12" x 38".

Am I probably safe with the large window? Any recommended sources?

 

[edgephoto]

Have you tried calling a glass shop? LMC has listings for glass. GM made millions of these trucks. Should be a no brainer to find glass.

Local glass company will be best because when you pick it up you can check the fit right there. If there is an issue they can see it. I doubt you will have a problem with glass shop.

 

[Chris64]

Yeah I tried a couple glass places. Their suppliers don't have them.

LMC has it and charge more for shipping than the glass but I guess that's to be expected.

 

[TotalyHucked]

There are no "large" or "small" back windows in these trucks. They're all the same size as far as solid glass. There are differences in the sliders however. GM sliders use the same gasket as the solid back glass, aftermarket ones typically use a different gasket. But the opening in the cab is all the same. The only squarebodies that got a small back glass are medium duty trucks

So you'll need this if you want tinted glass:

Back Glass - Green Tint - 73-75 Chevy GMC C/K Pickup

Back Glass - Green Tint - 73-75 Chevy GMC C/K Pickup Reproduction back glass for the 73-75 Chevy / GMC C/K Squarebody Pickup Made like OE. Each piece feature the correct shape, size, bends and curves. Upgrade the rear window of your Squarebody Chevy GMC C/K Pickup with this high-quality Back...

www.autometaldirect.com

This if you want clear:

Back Glass - Clear - 73-75 Chevy GMC C/K Pickup

Back Glass - Clear - 73-75 Chevy GMC C/K Pickup Reproduction back glass for the 73-75 Chevy / GMC Squarebody C/K Pickup Made like OE. Each piece feature the correct shape, size, bends and curves. The back glass is a vital component of any vehicle as it provides visibility while protecting the...

www.autometaldirect.com

This gasket:

Back Glass Gasket Seal w/ Trim Groove - 73-91 Chevy GMC C/K Truck

Back Glass Gasket Seal w/ Trim Groove - 73-91 Chevy GMC C/K Truck This rear window seal goes first on the body then the glass is placed in the opening. Tucking in the self locking strip secures the glass in place. Made from ozone resistant EPDM rubber and from the same OE specs as the original...

www.autometaldirect.com

The trim:

Chrome Rear Window Gasket Lock Strip w/ Corner Joints - 73-91 Chevy GMC C/K Truck

Introducing the Chrome Rear Window Gasket Lock Strip with Corner Joints, meticulously designed to cater to the 1973-1991 Chevy GMC C/K Truck as well as the rear quarter windows of the Blazer, Jimmy, and Suburban. This unique accessory is an essential component that not only enhances the visual...

www.autometaldirect.com

 

[Keith Seymore]

There are no "large" or "small" back windows in these trucks. They're all the same size as far as solid glass. There are differences in the sliders however. GM sliders use the same gasket as the solid back glass, aftermarket ones typically use a different gasket. But the opening in the cab is all the same. The only squarebodies that got a small back glass are medium duty trucks

Agree.

K

 

[Grit dog]

If it’s a decent slider you could probably get someone to trade you for a solid window. If you were closer, I would.
Worth mentioning I’m almost certain someone, Precision maybe, finally makes new weatherstripping for sliding windows if that’s the issue with yours. (For the sliding panes, not the big installation gasket.)
Also fwiw, the rear window installs pretty easy. Way easier than the windshield.

 

[Chris64]

There are no "large" or "small" back windows in these trucks. They're all the same size as far as solid glass. There are differences in the sliders however. GM sliders use the same gasket as the solid back glass, aftermarket ones typically use a different gasket. But the opening in the cab is all the same. The only squarebodies that got a small back glass are medium duty trucks

So you'll need this if you want tinted glass:

Back Glass - Green Tint - 73-75 Chevy GMC C/K Pickup

Back Glass - Green Tint - 73-75 Chevy GMC C/K Pickup Reproduction back glass for the 73-75 Chevy / GMC C/K Squarebody Pickup Made like OE. Each piece feature the correct shape, size, bends and curves. Upgrade the rear window of your Squarebody Chevy GMC C/K Pickup with this high-quality Back...

www.autometaldirect.com

This if you want clear:

Back Glass - Clear - 73-75 Chevy GMC C/K Pickup

Back Glass - Clear - 73-75 Chevy GMC C/K Pickup Reproduction back glass for the 73-75 Chevy / GMC Squarebody C/K Pickup Made like OE. Each piece feature the correct shape, size, bends and curves. The back glass is a vital component of any vehicle as it provides visibility while protecting the...

www.autometaldirect.com

This gasket:

Back Glass Gasket Seal w/ Trim Groove - 73-91 Chevy GMC C/K Truck

Back Glass Gasket Seal w/ Trim Groove - 73-91 Chevy GMC C/K Truck This rear window seal goes first on the body then the glass is placed in the opening. Tucking in the self locking strip secures the glass in place. Made from ozone resistant EPDM rubber and from the same OE specs as the original...

www.autometaldirect.com

The trim:

Chrome Rear Window Gasket Lock Strip w/ Corner Joints - 73-91 Chevy GMC C/K Truck

Introducing the Chrome Rear Window Gasket Lock Strip with Corner Joints, meticulously designed to cater to the 1973-1991 Chevy GMC C/K Truck as well as the rear quarter windows of the Blazer, Jimmy, and Suburban. This unique accessory is an essential component that not only enhances the visual...

www.autometaldirect.com

I just got a one piece rubber gasket (no groove). I may live to regret that. I've done this before on a Toyota so I'm familiar with the process but I'm sure the fit won't be easy.