Identifying Frame Please HELP

[bigtimbo]

A while back I bought a 1969 4x4. The vin shows that it is a f100 2wd. The frame is 4wd with leaf springs and it is a 250 ( It has 8 Lugs ). I can not find the vin on the frame underneath the passenger seat. In technical articles I see I can measure the frame width to see if it is 34" or 38" wide. I measured the frame inside to inside of the rear frame and it was almost 34.5". Are you suppose to measure inside to inside or outside to outside of frame. When I bought it I was told that someone told the owner it was a 1977 frame but I do not know how he knows that. Please help. Any other ideas to identify it?

Thanks!!

[averagef250]

The VIN is inline with the firewall on the top rail of the passenger side frame rail.

34.5 is a 34" frame. "34" frame" isn't just a Ford thing, it's a standard used by all the automakers for their heavier trucks for a very long time, many still use it. It allows aftermarket truck bodies/beds to be interchangeable to some degree. Highboys all had 34" frames from 67 through 77.5.

If it's a 77 frame it will have a tapped hole in the driver's side of the frame for the power assist steering hose clamp. It will likely have all the disc brake pieces in factory clamps including the proportioning valve and the special disc brake hose brackets that fix the ends of the hard lines. A 77 highboy steering box will have a pitman arm with a D6XX part number because the steering arm was redesigned for disc brakes in 76.

If the front axle is original to the chassis it will be a low pinion open knuckle disc brake 44 with external lockout hubs (6 3/8" bolts hold the lockouts onto the hub body).

If the rear axle is original it will have around a 65" WMS measurement and have 30 spline axles instead of the 16 spline used prior to 1973.

[bigtimbo]

Average,
Thanks for the detailed response! I will check everything out this week sometime.i'll let you know what I find out. I can't wait to find out what year the frame is.

[Art]

I can not find the vin on the frame underneath the passenger seat.

I have found the VIN stamped into the top of the passenger's side frame rail over the front axle and also again under the passengers floor pan.