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Old 03-31-2011, 12:58 AM
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lt1silverhawk lt1silverhawk is offline
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Hey Bullsnipe,
Originally Posted by Bullsnipe
Hi, I am a former California Smog Tech. I moved from the Left Coast in 1998 so I have been out of the loop for some time. I understand the Tech not wanting to "Pretest" We were required to scan the barcode on our license before we could start the test. We were required to manually exercise the EGR valve and note a drop in RPM. I know that 12 years ago that behind closed doors the test could be faked. You test a good vehicle but enter the data for the vehicle you want the cert for. We had manuals that specified all the smog equipment that was required. When in doubt, the customer would have to take his vehicle to a Cal Referee.
The tech took one look under the hood and, after realizing that there was no EGR, pulled out a thick book and looked up my truck. I'm not sure under which specific model he searched (C/K 10/20 etc) but for the 350 engine, he said there should be an EGR. I took his word as final answer because I've known him for so long, and he seemed dead set against testing my truck. But now I believe it is a good idea to try another shop. Not sure who the refs are but I'll ask.

As to the pretest, it is advertised at their shop as an available service in case the owner thinks the vehicle might fail. Kind of like a practice test I suppose to see where someone is weak at. Then again, as jaded as the tech has become, he could've just been having one of those days.

Thanks, I appreciate the tips and info Bullsnipe! And welcome to the site!

Originally Posted by cobalt327
What I was wondering was, is the VIN plate missing from the dash where I would expect it to be (leaving 2 holes in the dash), and that the tag you now have was a "replacement" for whatever reason? Or is this tag in that dash location now?

Because there should be a manufacturer-attached VIN tag, not just a tag from CA, unless this truck has had considerable repair work or repair that would encompass replacing the original dashboard assembly, or it's a resurrecting junked or "rebuildable" vehicle, or whatever.
Originally Posted by 75gmck25
My truck (which is a '75 GMC) has a data plate riveted to the door frame, just below the striker post on the driver's side door frame. This plate has the VIN number, and it also lists GVWR (8400 lbs for my truck), and the front and rear axle weight ratings. This is supposed to be the stock data plate location for 73-78 GM trucks. Have you tried looking for a data plate in that location?

This URL shows a picture of a similar data plate (mine is a little different)

Sorry cobalt327 and Bruce, long day today. There is no VIN on the dash, nor any holes where it should be at. Instead of the data plate, the "Assigned Identification Plate" is riveted to the driver-side door frame below the door striker. Aside from the sticker I posted, I was unable to find any type of tag from the manufacturer. If the truck had been extensively repaired, wouldn't it be titled as salvaged (it isn't).

Originally Posted by cobalt327
Does the VIN that's on the plate follow the format shown HERE? If not, the original VIN plate may have been removed, or the vehicle is rebuilt, etc.
The VIN on the plate does follow that format and it comes out as a Light Duty Chevrolet Conventional Cab 4x4, 350 165 HP 4 bbl, 3/4 ton, Cab and Pickup Box or Van with Hi-Cube.

Going by this page, if I go by the RPO codes on the sticker(provided mine are correct), the 4.56 ratio rear axle, a a 350 V8, and TH400 were offered with 4wd in the K20.

Last edited by lt1silverhawk; 03-31-2011 at 01:08 AM.
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