Chassis Research

[HybridK]

I've been a member for a couple years but haven't posted. Been busy trying to hash out things my own way (the dumb way). I've got what is clearly a mutt. It's got a 72 cab, 67 bed, 70 grill, 69 bumpers, an LT1 (Gen 1 SBC), CUCV axles (80s), and late 70s trans and transfer case. I'm pretty sure the frame was originally prepped for an auto trans because the bracket for the bell crank on the frame is definitely home made. I was hoping someone out there could tell me where to get information like where to find the VIN on the frame, how to read it, and also how to find out what engine it originally had in it, what trans, etc. Also, to correct the geometry of the clutch linkage, can anyone give me dimensions and reference points for where the mounts need to be? If you need to know the VIN I can get it in a couple of days. I'm willing to bet this information has already been posted but the internet out here (Afghanistan) is horribly slow and it would take literally forever to find. I'm hoping to dive right back into the truck when I get back. I can't wait to drive my baby again. Thanks, guys!

[PanelDeland]

The frame is usually marked on top just about even with the steering column.If the truck is a "mutt" as you say,determining the original setup will depend on whether you're interested in the frame or cab VIN.They may be the sae and much of the info can be found from that.I don't have the answers to the rest but someone on here has the info.

[HybridK]

The VIN just says that it's a 1/2 ton, 4x4, Gas V8 from Oshawa. I was looking to see if I could find out whether it was originally a big block or small block truck (the owner before the guy I bought it from had a big block in it), what the original color was (it's got baby blue under yellow, then the current burgundy), and what option package it was. I don't remember seeing anything stamped on the back of the glove box, and there isn't a sticker or a plate anywhere other than the VIN plate. I wanted to know about the frame VIN to see if the frame actually belongs with the cab. I've read a few posts about "numbers matching" trucks. I know how research this with muscle cars, but there are a whole lot more resources in those fields. I'm not trying to completely restore it back to numbers matching status or anything, but I would like to at least get it in the ball park of original.

[SS Tim]

This isn't that hard to sort. Looking for a frame number is a good start. As far as big Blocks go there were no know factory production BBC 4x4 pickups. If it had a BBC it was swapped in.

A picture of the frame might be the easiest starting point. But overall is it kind of straight forward. There are dimensions for the engine mounts, the trans bellhousing mount crossmember and the trans rear mount for automatics. These are all engine specific.

There is a drawing or two that might help you but what exactly are your plans? Are you going to rip everything out and go to stock if we can determine what stock is? Or are you going to make work what you have where it is. If that is the case does LT1mean a documented 'vette block/engine that will go into the stock small block locations?

Here is a shot of the factory clutch linkage from the service manuals. If you don't have the set (service/overhaul) they have a lot of material and can be had on CD.

The others are of a SBC/manual Blazer frame.

[ChevLoRay]

The VIN's on these trucks will not tell you which engine it had when new. It will tell you whether it was a 6 or an 8. The SPID on the inside of the glove box door, if it is correct for the VIN that is on the chassis, will tell you which engine, transmission, etc. But, those glove box doors are easily removed. SPID sheets are easily defaced, or painted-over.

But, there are two places where you can find the VIN, okay a portion of it, on the frame. On the drivers side rail, beneath the cab floor and also ahead of the firewall. I'm gonna attach a pic of mine....you can reference where on the frame rail the VIN is, based on the position of the rear end that is beneath the frame.

[HybridK]

Thanks for the info and pictures, guys! I'm planning on leaving the driveline mostly the way it is with the exception of rebuilding and cleaning things up. The engine probably came out of a Camaro, not a vette. It's not "documented", but it's a fair assumption based on the casting numbers on the block and heads. I got it as a long block that needed a lot of help (read: mice in cylinders, and the corresponding urine welding the rings to the bores), got it bored 0.040 over, line bored and honed it, new pistons, rings, bearing, etc. Ran it in my old race car for a few seasons then gave it to my uncle (previous owner of the truck) to replace the blown big block that was in it when he bought it. Anyway, I was looking to find out which V8 it had for proper badging, what color it was when it left the factory, etc. Is there a registry through GM where based on the VIN you can get this info? I know for a fact that the factory option listing for this truck is gone: glove box door was replaced. Thanks again for your help!

[Daves70]

I went through this with my 69 Camaro a few years ago. Well worth the money for GM Canada to do this ($60 or $70 if I remember). They sent me a sheet with all the original equipment and options my car came with and had the name of the original dealer. Also the number imported to Canada and the date shipped.I also got a copy of a 20+ page sales brochure. Someone at a car show said that they were stopping this service so if it is still available I would do this as soon as you can.

[HybridK]

Thanks for the info, guys. I'm going to give Oshawa a call when I get back to the states. I hope they're still releasing the info you described. I'd be pretty bummed out if I couldn't get it. I'm not going for a numbers matching truck or anything. I'm very happy with the driveline in it, and I always liked the 1970 grille more, haha. I'm more curious about it than anything. I am interested to know what color it was originally and stuff like that, but it's not a huge deal. I'll be keeping the current small block in it regardless of what I find out about it. I'll be doing more performance mods (looking for around 600lb-ft and around 550hp), but nothing that would drastically change the appearance of the truck. When I get the time and cash I'm tearing it apart, blasting the whole thing down to bare metal and doing everything the way I want it. I'm a "better mousetrap" kinda guy, so I'll be doing a lot of mods aimed at increasing longevity and fighting/preventing rust. I've already updated it to 4 wheel disc brakes and put a Painless harness in it, I'm looking into hydroboost and LOTS of stainless hardware and lines next. I just want it to be clean and rust free. It'll be a whole lot of work, but I've wanted this truck since I was a kid, so it's worth it to me. Thanks for all of your input, and if you or anyone else needs BBC info give me a hollar.

[huahuamick]

Really good thread!