Suspension swap for my 49

[wycheguy]

Hello all
I just picked up a front and rear suspension from an 81 chevy truck that I plan on putting in my 49. My question is what is the drive gear size, and will I be able to get relatively good gas milage with a 350 tranny? If not, what other acceptable arrangements are there for me to use?
Thanks for your help

[chevytruckfan]

Glad to hear you are keeping you truck all GM and not using the Mustang II weld in. I am sure you will find it much easier to install. As far as the gearing goes, there is a tag on the housing cover. If not you will have to unbolt the cover and the ratio should be stamped on the ring gear. i.e. mine looks like 11:41. Divide the big number by the small one and you have your ratio. In this example mine is 3.73. The smaller the number the better gas milage you will get. With my ratio I am running 3000-3500 RPM on the highway. You will get better mileage if you have a 3.08 or 3.42 ratio.

[tommo]

careful- the track width may poke your wheels/tires out the fenders, unless maybe you plan on using the stock wheels from your truck, but '81 was 5 lug....