F-100 4x4 hub face to hub face dim same front to back?

[stldesign]

Well we started to swap the newer front and rear axles for the old and I noticed the rear end I was taking out was about 62" from face of drum brake to face of drum brake. But the new rear end (supposed to be from a 1979) is about 66" from face to face.

BUT the old front axle and the new are around 66" also. Is this correct or did someone swap in a narrow rear end in the truck at some point??

This is a 1969 f-100 4x4

[stldesign]

58.00 1966-1977 Bronco
61.25 1957-1972 Ford F-100 Pickup
65.25 1973-1986 Ford F-150 Pickup
65.25 1978-1986 Bronco

Found my answer above.

Why did ford run a narrow rear with a wider front axle? 2" wider each side.

Can you put a 78 9 inch center section in a 1969 9 inch rear end?

If not i may take the 79 rear and have the spring perches moved in 2" each side.

[cep62]

Why did ford run a narrow rear with a wider front axle? 2" wider each side.

I don't know , it must be a carry over from the older models.

Can you put a 78 9 inch center section in a 1969 9 inch rear end?

"76-"79 have 31 spline axles Most older models have 28 spline.

The later axles have a better wheel bearing that'll handle more abuse.

[stldesign]

Found a shop that will do new spring perches and shock mount for around 200. Dropping it off tomorrow.