originally equipped with catalytic convertor?
 

I have a 1987 Chevrolet R20 3/4t, 2wd, regular cab longbed. It does not have cats now, but it looks like it might not have had them originally either. It has the 454 engine and I have been told it might not have had them from the factory do to its combination of 3/4T and the 454...

I don't know and the question has arrisen based on a state visual inspection of the exhaust system. The state requires a visual inspection for cats and muflers for vehicles 1984 and newer. The exception is some trucks where built without the cats from the factory, and if I can provide that info, then mine is exempt from that. No where on the truck can I find a label or sticker that indicates it should have them....

Can anyone shed some light on this? I know I should be able to look at the SPID or the vin number to get this info, but what info or code am I looking for??

Re: originally equipped with catalytic convertor?
 

I'm guessing an 87 3/4 ton would have cats from the factory. I've had a couple 86-87 3/4 tons and they had cats. Maybe the 1 tons didn't have cats.
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Re: originally equipped with catalytic convertor?
 

This is from the information packet from the GM Heritage Center archive and indicates that all gas engines had catalytic convertors in the 1987 model year.

K

http://i23.photobucket.com/albums/b3...ps1a3c339d.jpg

Re: originally equipped with catalytic convertor?
 

when i originally bought my '85 crew 1-ton it had no cat, don't think the p.o. (Forest Service) would have taken it off.

try this
http://www.rpocodes.com/GM-RPO-codes...NthroughS.html
scroll down to NA1, emission codes start there. see if any match your spid

Re: originally equipped with catalytic convertor?
 

I also have an 87 R20 3/4t, 2wd, regular cab longbed, but with a 350 instead of the 454. And I actually have 2 cats. One before the muffler and one right before the tailpipes. This is also as far as I can tell the factory exhaust.

Re: originally equipped with catalytic convertor?
 

Thanks guys...

I'm glad Keith was able to post up that page from the archives. I figured he would be the one to have access to the correct info and not do any guessing....

I knew from previous trucks the small block trucks had the cats on the 3/4T models, but did not know for sure on the big block. This truck is as original as I have seen in a long time and there is no indication that it had cats...I will look at my spid and see what codes are there....

Re: originally equipped with catalytic convertor?
 

so you failed insection due to no cats on exhaust?....in Longview?

Re: originally equipped with catalytic convertor?
 

Someone did you a favor by removing the Cats, saves you from having to do it yourself.

Note: your muffler guy by law can not do this but if the cats aren't there he can just run exhaust pipe.

Re: originally equipped with catalytic convertor?
 

If the truck came from the factory with cats, won't he need cats to pass an emission test? I would think everybody and their brother would be ripping off the cats and just saying "I don't know, it was like that when I got it derp derp."

Re: originally equipped with catalytic convertor?
 

the old timers here yanked the cats off everything, I know my old grandfather did on every truck he had, (probably even his last new one the 97 F150)

Not all states do emissions testing.... commonly referred to as "free states" (had to put that joke in)

But removal of the cat's gains horsepower they rob. environmental impact... minimal at best, still probably less than your weed eater or other two stroke devices.

Got to be an outlaw where i can be right?

Re: originally equipped with catalytic convertor?
 

Yep, fail inspection at two different places. Each was cool about it and did not charge me (in Texas, by law, you are charged weather you pass or not.)

The cats on '84 up models are just visual unless you like in a metropoliton area such as Dallas, Houston, San Antonio, Austin which have areas that do an actual emissions test with a sniffer in the tailpipe. Here in Longview, its just a visual test. The last place I went even said the High Beam indicator was out and that would cause it no to pass the safety inspection along with a manifold exhaust leak that is minor, but they heard it and said that was the major reason for not passing it. The other place stopped when he so the truck had no cats or mufflers. I had to point it out to him that the two glass packs where on there and those ARE mufflers...he looked again and said OK, but you still don't have cats...

I need to find someone that will look the other way and pass it so that I can drive it ocasionally with out the cops stopping me for an out of date inspection sticker....

This weekend we plan on putting on manifold gaskets and fixing the indicator bulb and try again....

Re: originally equipped with catalytic convertor?
 

if they just visually inspect for the cats, there are a couple dirty tricks you can do there, or so I've heard, something about a rod not that I'd know anything about that, or had relatives who've done that.

Option B is know the guy, here the last few years i had to do the inspections just put the sticker on and took your $5, didn't give a flip if lights or blinkers or anything else worked.

The indicator bulb if its the bulb is easy those just twist out, if its the socket bend the tabs up more to get a good connection to your circuit board.


Here in Oklahoma about 12 years ago Gov. Keating did away with vehicle inspections because it cost you $5 but the state cost was a lot higher so he just axed the inspection stickers and inspections.

Re: originally equipped with catalytic convertor?
 

You really are a redneck. If everyone did and thought as you do the sky would be brown and the air would be poison. Get real dude

Hey heres an idea, put cats on it. Do your part. Not like you can't afford it.
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Re: originally equipped with catalytic convertor?
 

when i lived in sealy they never even looked under the truck!! and my cousin had a 87 that didnt have a cat on it, not sure why my uncle bought the truck new and as far as i know the exhaust was stock


oh and if its just visual just weld the shells of a cat to the exhaust

Re: originally equipped with catalytic convertor?
 

in Tx your truck is officially antique, call the DMV and find out exactly what you need.


Redneck.... well i'm sure my one little 305 that gets driven 20 miles a week (lately) and has been driven 2000 miles in the last 15 years, has made any noticeable environmental impact..... besides its not like there are 5 million cars out on the roads in this half the country that don't run them. Fact is they restrict exhaust flow, when i got the truck it did not have them (dad pulled them in about 84) I am blessed to live in a state where they do not check these things, just saying.

Redneck would be doing the bare minimum and running stub pipes out just behind the cab, no muffler just straight pipes... or worse toss a diesel in it and install those ungodly exhaust stacks up behind the cab.

Re: originally equipped with catalytic convertor?
 

I hear these pass the visual easily:

http://www.siliconeintakes.com/parts...6b67093b6f7abc
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Re: originally equipped with catalytic convertor?
 

That's not much better vs. the statement you're blasting. While I don't condone removing emissions equipment just for the sake of removing it, just because a vehicle doesn't have cats (or similar equipment) doesn't mean it's now a gross polluter. Only testing can tell. The problem is, our bureaucracy allows for 'blanket' coverage that utilizes a visual pass/fail regardless of effectiveness.

The problem w/this logic? 2 cats = still illegal (unless it came from the factory w/2 cats which GM trucks didn't back then). The cat/s also must be close in proximity to where they were installed from the factory (2 into 1 to cat to muffler).

I've had more than 1 set-up run as clean or cleaner w/illegal set-ups vs w/required emissions legal items in place based on sniffer testing.

I feel we should all do our part to keep emissions output within the limits set by the government to help air quality. How creative we are @ reaching that goal should be left up to the individual (EX: 2 cats (true dual exhaust) should be good if installed properly & are fully functional; an air pump isn't mandatory if the vehicle can pass w/o it, etc...)

Re: originally equipped with catalytic convertor?
 

http://www.lmctruck.com/icatalog/cc/full.aspx?Page=158

Parts # 36-5595 & 36-5596

Re: originally equipped with catalytic convertor?
 

Brown air that was a classic comment,.... if you are so worried about the environment why are you driving a carburetted (most likely) V8 pickup rather than a prius.... or beings your a yuppie from the city they have the city bus.

You know i even recycle my oil.... and in a very good way.... I dump it in a producing oil well. my 5-6 qts of motor oil gets blended back into the crude supply... now i wouldn't suggest this but i happen to have a producing oil well in a side yard, and i wouldn't pour 50 gallons in the nearest oil tank. but the amount from one change once every 3 months is alright.

Re: originally equipped with catalytic convertor?
 

http://i367.photobucket.com/albums/o...bea57b7445.jpg
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Re: originally equipped with catalytic convertor?
 

Yes,
You can have it all.
Al Gore told me so. It was just hard to hear him over the banjo music at my house.
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Re: originally equipped with catalytic convertor?
 

Lol at this entire reply
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Re: originally equipped with catalytic convertor?
 

Owned two 1986 K20 trucks, one had cats, one didn't. Engine code M was HD emissions with no cats. Engine code L was light duty with a cat. Looked in my 87 GM service manual, there is two 454 engine codes, W and N, carbed vs TBI. But like Keith stated all gas engines of this year were equipped with cats..
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Re: originally equipped with catalytic convertor?
 

oh i forgot, get farm truck tags, i dont think there is inspection for them, i know for a fact historic vehicles dont have to pass an inspection

Re: originally equipped with catalytic convertor?
 

emission testing in general has shown that only 4% of vehicles dont pass.4% is an insignificant number....meaning at a 96% pass rate with todays newer car technologies we no longer need to waste BILLIONS of tax payer dollars on testing and all the related BS ....my 88 crew 454tbi has the cat cut out from po and i will pull the air pump ( exhaust dilution system ) when i install headers.My 90 crew 350 tbi runs headers duals no cats......luckily by some miracle or oversight the save the planet do gooders in this liberal state have not mandated testing in the county I live in ....guess I will have to get creative when they realize they have missed an opportunity to steal from its tax payers