Bend in drivers side frame rail?

[oldpurple]

I'm still getting to know these trucks so I'm not sure if this is a 'thing'.

Story: My truck has a bit of a bend in the lower flange of the drivers side frame rail. It doesn't concern me much but there doesn't seem to be any damage or marks or any explanation of why its there.

I was recently browsing a thread about transmission crossmembers and noticed a picture of the same thing. Post #11

Here's a picture from the other thread (I don't have one of my own):



Mine never had a catalytic converter but I see what kind of looks like a heatshield above this area in this picture.

Anyone got an explanation or is this just a weird coincidence?

[bbbc10]

its normal

[andrewmp6]

What year is your truck ?Some one could have removed the cat from it.

[oldpurple]

Originally Posted by andrewmp6

What year is your truck ?Some one could have removed the cat from it.

1979 Heavy Half. Never came with a cat as far as I understand.

[andrewmp6]

in 75 trucks under 6k gvw got a cat,78 gm changed the frame to fit the cat better,And in 79 all got cats up to a 8500 gvw on them.Yours should have had a cat on it,But when they clogged up or stopped working some people did remove them if they didn't have smog testing.

[oldpurple]

Originally Posted by andrewmp6

in 75 trucks under 6k gvw got a cat,78 gm changed the frame to fit the cat better,And in 79 all got cats up to a 8500 gvw on them.Yours should have had a cat on it,But when they clogged up or stopped working some people did remove them if they didn't have smog testing.

Hmm, that is interesting. I'm wondering if being a Canadian truck changes that a bit?

I'm not saying you're wrong but if someone removed the cat then they would have changed the entire Y pipe as well. Mine also doesn't have a heatshield like in the picture.

I also had a '79 almost 10 years ago and it had no signs of a cat either. Now I want to dig into this a bit!

[SkinnyG]

My Canadian-market '77 has the bend in the frame, and originally came with a cat.

[ont_guy_38]

It's factory

[Front Range]

Got a 79 with the same bend, I always figured my Grandpa hit something with it on his Farm. Good thing I never got around to "straightening" it out.

[65standard]

My '85 Canada built C/10 was the same way. I corrected it during my frame off build. I thought it was damaged, so I put it on a frame table and fixed it.

If they are all like that, I guess I didn't need to do anything with it. Too late

[ElGracho]

http://67-72chevytrucks.com/vboard/s...d.php?t=281521

http://67-72chevytrucks.com/vboard/s...ad.php?t=60525

http://67-72chevytrucks.com/vboard/s...d.php?t=403972

[Axle]

Canadian emmisions equipment and cat use on trucks is all over the map, especially around 1980. Just as an oddball non-truck example, a 1979 Chrysler LeBaron (Dodge Diplomat, Plysmouth Caravelle) MIGHT not have had a cat from the factory. Wish I could remember the details, but it was a specific engine and carb option. It is not well documented outside factory literature since the general rule of thumb has been cats on all passenger cars since 1977, but there are a few exceptions to the rule. Trucks even more-so. Its also one reason I suspect why Ontario never included anything older than 1981 when they went to e-testing early in the 2000's.

Other useless emmisions trivia: 1983 is a common year for US cars to get into the feedback carb, here in Canada a 1983 Camaro still had a non-feedback carb. Same for trucks, you guys got the full feedback carb and computer a couple three years before it showed up here.

My old '83 C10, 305 4bbl, no air pump, standard carb. Just EGR and a Cat
My '81 C1500, same thing. Certain models where also Cat free.

Alex.

[oldpurple]

Originally Posted by Axle

Canadian emmisions equipment and cat use on trucks is all over the map, especially around 1980. Just as an oddball non-truck example, a 1979 Chrysler LeBaron (Dodge Diplomat, Plysmouth Caravelle) MIGHT not have had a cat from the factory. Wish I could remember the details, but it was a specific engine and carb option. It is not well documented outside factory literature since the general rule of thumb has been cats on all passenger cars since 1977, but there are a few exceptions to the rule. Trucks even more-so. Its also one reason I suspect why Ontario never included anything older than 1981 when they went to e-testing early in the 2000's.

Other useless emmisions trivia: 1983 is a common year for US cars to get into the feedback carb, here in Canada a 1983 Camaro still had a non-feedback carb. Same for trucks, you guys got the full feedback carb and computer a couple three years before it showed up here.

My old '83 C10, 305 4bbl, no air pump, standard carb. Just EGR and a Cat
My '81 C1500, same thing. Certain models where also Cat free.

Alex.

Thanks for the info. I am pretty confident this truck never had a cat. It also doesn't have EGR or a charcoal canister or anything else.

[Keith Seymore]

Originally Posted by oldpurple

Thanks for the info. I am pretty confident this truck never had a cat. It also doesn't have EGR or a charcoal canister or anything else.

Even if it didn't the frame rails would be common across 1/2 ton applications and would accomodate worse case packaging.

We wouldn't proliferate frames to have cat vs non cat part numbers.

K

[oldpurple]

Originally Posted by Keith Seymore

Even if it didn't the frame rails would be common across 1/2 ton applications and would accomodate worse case packaging.

We wouldn't proliferate frames to have cat vs non cat part numbers.

K

Yes I understand that. I'm mostly referring to the comment in post #5

[79sierra]

Yup, my 79 has same bend as well. I almost bought another frame when I started my build then noticed both frames had same bend.