Gear Ratio by VIN???

[Leadfoot]

I found a 79-80 GMC K35 and there is no glovebox sticker or door sticker left on it. It was originally diesel and has a sticker in the glovebox that mentions something about a camper (camper special maybe????). What are the chances it has 4.56's (not sure diesels used that high a ratio but not sure?????) and is there any way to find out somehow (maybe through a GM dealer) by the VIN code which I can get, but I can't get to the truck right now otherwise I would pull the cover.

 

[91K5]

The VIN number wont have the axle ratio, only the year/type/engine/serial number of the car. There is a stamping on the axle tube that has a # that tells you the gear ratio and a posi/locker of any kind, but its easier to pull the cover than to read one installed on a vehicle. I don't think a diesel truck would have that low of a gear, maybe 4.11's but I'm really not sure.

 

[70~K5]

The '85 ford dually diesel I had came stock with 4.11s and a close ratio 4 speed truck trans. And it had 215/85R16"s.

 

[Zeus33rd]

The little ID tag is only on the front diff cover. GM never put them on the rears of a 4x4. Check the front cover and see what it says. If it's still there that is. Sometimes the tags arent re installed when the cover is pulled. If the tag is there, it will be bolted on with one of the cover bolts. Might have to scrape some grease and crap off to see it of course. Should be one of the bolts near the bottom of the case.

 

[Leadfoot]

I don't have the truck to look at. All I could get is the VIN. I know how to decode the VIN and that it does not tell you the gear ratio, but I wasn't sure if a GM dealer could tell you/me by looking at a database of VIN's. At one point they used to be able to tell when and where a vehicle was sold by the VIN, I was hoping I could get lucky and they would also have the specs on the vehicle too (gear ratio being one of them). I know somebody could have swapped them, but on this rig it is very unlikely. I just didn't want to go to a dealer and ask if they could do this and look like a total idiot.

 

[70~K5]

To bad pass. cars and light trucks aren't like big rigs. I can go to my Peterbuilt dealer with the last 6 of my vin and they have the build sheet on computer. An IH dealer can do the same for a Scout, but it's still a Corn Binder. /forums/images/icons/laugh.gif

 

[Leadfoot]

That's actually what made me think of it. One of the guys I do truck pulls with is a diesel mechanic and he was telling me about build sheets and how some passenger vehicle dealers used to provide them as well (but he wasn't sure if they still do). I was going to go to my local dealer and ask but didn't want them to stare at me with a blank face and wonder what the heck I was talking about.

 

[70~K5]

Sometimes you can find the build sheet tucked under the springs on the seat.

 

[91K5]

The build sheet in GM cars was not mandatory to be put in. It was for the workers to know what parts that varied to be put in a specific car, sometimes they grabbed the sheet and stuck it in the car, most times they didnt. I'm still searching for mine in my '72 Chevelle with no luck so far. A truck in that era would probably have had the sticker in the glove comparntment instead of the regular build sheet I think, my '80 Blazer had it there. A dealer might be able to give you a clue, but the problem is GM didn't keep records of VIN's and the specific options on cars so its not real likely.