Technical How do I find out what year my frame is?

I have a '49 Merc that was put on a later Chassis by a previous owner. Its a Cadillac chassis but I don't know the year. Late 70's is what I can figure by the equipment. Anyone know where to find numbers that would give me a model year on a later chassis?

 

Assuming it is a 70s with 13 digit VIN here is a decoder straight from the Cadillac Power Forum:

 

I would look on the cast iron parts such as brake calipers and rearend housing, for casting date codes. It's kind of a long shot, but might work. Also if you pull the rear end cover plate off, you should find the month/year the ring gear was made, stamped into it. such as 8 77

 

Thanks NM, but the numbers on the forward edge of the windshield molding don't exist in this case. Its a Mercury body. I'm sure there are numbers somewhere on the frame

 

my guess for the location of the number would be on top of the driver side frame rail, probably under the driver seat positon. And it would likely be a partial VIN, with the GM division, model year, and plant being the first three characters, and the serial number being the last 6 digits.

But this is all a guess....

 

Pull a front wheel and measure the distance between the pins that hold the caliper on.

That will indicate early style versus late style.

If it is a tick over 7", it is a 1969-1977 chassis. If it is 5-1/2", it is a 1978-1988 chassis.

This will get you in the ballpark for purchasing replacement parts.

 

Go to a compitant brake shop or alignment shop. Put it on the hoist. They should be able to narrow it down real close by looking at the related parts.