K10 1976 catalytic converter?

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SquareSweeney

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Hey, complete jackass here looking for information on my un-smogged Cali 1976 k10 short bed.
Does anyone know if California Squares from 1976 had to have Cats, or came stock with them? When I bought it, the truck only ran exhaust up to the muffler under the cab, nothing under the bed.
I gotta get the damn thing smogged and cant seem to find any information on it.
It seems so close to 1975 which had no cats, but since 76s have to be smogged i'd assume they'd put on one.
Any information would be appertained thanks.
-sincerely ignorant
 

hatzie

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The 1/2 ton probably had a cat.
 

Craig 85

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It depends if you have HD emissions. I know I had a "77 K5 that came with a small block 400. It ran on regular and did not have cats. An easy way to tell if your truck rprobably had a cat is check the fuel filler restrictor. Trucks that ran on unleaded had the smaller hole.
 

legopnuematic

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If you are fairly certain that the fuel gauge is the original to the truck, if it says unleaded fuel only then the truck came equipped with a cat. If it doesn't then it didn't. Only go by this if you are 100% that the gauge is original.
 

bucket

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I've had two '77 K5's that were non-cat. Both had dual exhaust when new and had a heat shield above each muffler. I don't know if the pickups also got heat shields, but if there's shields for two pipes, then there was no cat installed when new.
 

bucket

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Oh yeah, also check the sunvisor. I had a '79 K5 with a cat, and there was a label on the visor warning that the truck was equipped with a cat.
 

SquareSweeney

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If you are fairly certain that the fuel gauge is the original to the truck, if it says unleaded fuel only then the truck came equipped with a cat. If it doesn't then it didn't. Only go by this if you are 100% that the gauge is original.

Hell yeah thanks for the help! Gauge should be original no one loved this truck enough for a new gas gauge damn thing was wired with orange extension cord when I bought it ,and no sign of Unleaded only label anywhere.

I've had two '77 K5's that were non-cat. Both had dual exhaust when new and had a heat shield above each muffler. I don't know if the pickups also got heat shields, but if there's shields for two pipes, then there was no cat installed when new.

Thanks for the response! sure enough heat shields over both mufflers. Sadly came with no sun visors to check lmfao.

It depends if you have HD emissions. I know I had a "77 K5 that came with a small block 400. It ran on regular and did not have cats. An easy way to tell if your truck rprobably had a cat is check the fuel filler restrictor. Trucks that ran on unleaded had the smaller hole.

Thanks for the response man! Searching HD emissions gave me the best answer leading me to the http://www.73-87.com/7387info/7387emislevel.htm which said "all 1976 and 1977 K10/15's and all 1975, 1976, and 1977 C/K 20/25/30/35's) did not use catalytic converters"

Again thanks for responding everyone saved my ass stressing over unnecessary expenses, like I don't have enough with this beater already haha.
 

75gmck25

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There should also be a VIN tag in the frame of the driver's side door, and it will list the GVWR of the truck. Starting in about the 1975 model year, catalytic converters were not required if the GVWR was 6000 lbs or higher. In 1979 they raised the GVW exemption to 8500 lbs and up. Chevy then had a suspension package option for the C/K20 that was rated at 8600 GVW.

The catalytic converted exemption for higher GVW's was what drove Ford to create the 6150 GVW F150 half ton in about 1974, and I believe Chevy's Heavy Half was created for a similar reason.

Bruce
 

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I read that the 1975 K20 was the last non catalytic pickup. The 1/2 tons were unleaded required in 1975 and all 1976's were catalytic.
 

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I assume the non-catalytic Chevy trucks were produced beyond '76, since I had a '77 Ford E150 that was ordered with a GVW package that made it exempt from using a catalyst. There were also the 3/4 ton HD models, which got converters even later. Chevy was following the same path, but I guess its possible that they changed over earlier than Ford.

Bruce
 

HotRodPC

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It depends if you have HD emissions. I know I had a "77 K5 that came with a small block 400. It ran on regular and did not have cats. An easy way to tell if your truck rprobably had a cat is check the fuel filler restrictor. Trucks that ran on unleaded had the smaller hole.
The gas guage would also say Unleaded Fuel Only. I don't think 76 had Cats even in Cali.
 

bucket

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I read that the 1975 K20 was the last non catalytic pickup. The 1/2 tons were unleaded required in 1975 and all 1976's were catalytic.

Nope, not at all. There were non-cat 3/4 and 1 ton trucks all the way through '86.
 

elcamman50

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I am the original owner of a 79, short bed, Big 10. Bought it new in June of 79 here in San Diego. Came with a catalytic converter. The sticker is still on my visor. It is almost 40 years old now and I still have to smog it every two years. Always passes with flying colors. Also owned a 76, K10, short bed, back in the 80s. It did not have a cat. I had headers and a holley on it and never had to smog it.
 

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If they fail it on not having one you'll have to go to the referee and find what your truck needs to pass.
 

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