68 GMC vs 70 Chevy cowl

[pwdcougar]

Is there a difference between a 68 GMC cowl and a 70 Chevy cowl? LMC catalog shows them as the same part number. Only difference I can see is the vent slots.

Paul

[68panelman]

I just ran out to the garage cause you got my interest, my 67 has the hole, but my 70 does not?, interested to see why. Possible a tooling change?

[pwdcougar]

Originally Posted by 68panelman

I just ran out to the garage cause you got my interest, my 67 has the hole, but my 70 does not?, interested to see why. Possible a tooling change?

I would think so. Maybe the later ones were stronger without the extra holes? My 68 cowl is in better shape and has the antenna hole in the right place. I know the 68 hood is slanted in the front but is the back edge the same?


Paul

[68panelman]

I just measured both cowls at the center and came up with the same measurement, I would think they're the same

[pwdcougar]

Thanks for measuring. Before this gets sandblasted though I'll see how it lines up with the 70 hood.

Paul

[Trevor]

I bet it's has more to do with supplier and assembly plant and all the variables that goes along with that, especially in the era of these trucks being built in 10 different plants, than anything else does.

I just looked at my '71 GMC and it has the holes/slots, it's a Canadian truck (built in Oshawa). So the 'correct' repopped cowl vent is anyone's guess, they all fit the same regardless.

[FirstOwner69]

Very interesting observation. I just checked the 3 cowls I have. The original from my 69 has the extra holes as does one without an antenna hole that I got from the junkyard a couple years ago. I got the one currently on the truck from the junkyard in the 70s or early 80s. It does not have the holes. I think the one without the antenna hole was on a 69. No idea what year the one on the truck came from. I am pretty sure all 3 are GM parts.

As stated above, they all fit. I assume it is either a supplier thing or varies by year. Probably a tooling change for more strength or cost savings.

[67chevy1series]

The only difference between 67 and 68 hoods is at the rear leading edge where the hood meets the cowl panel, when the hood is shut you can't notice any difference between them and it really isn't that big of a deal to have the 68 style on a 67 or vice versa (unless it bothers you. I just happen to buy my hood off a 67 and now have the 67 style on my 67.)

Here is the rear edge of a 67 hood. You will see the rear "flange" is folded over toward the long "horizontal arch" (for lack of a better term) and towards the edges around the side body lines it remains the same as 68-72 hoods (not saying the front of the hoods are the same between 1968 and 1969-72, just the rear edge)

[67chevy1series]

Here is that same edge on a 68 hood. Like I stated in my previous post there is no fitment issues if goods were to be swapped and with a proper gap between the cowl panel and cowl panel seal I doubt anyone could spot a difference with the hoods shut, however just another of many possible tooling changes between 67 and 68. It really would be cool to know why GM made them so different from each other yet they still look relatively the same.