1979Bronco diffrentials,akles,gears

[Big0]

i have a 1979bronco with a 4inch lift and 39.5inch super swamper tsl on 15inch rims i was wondering what would be a good akle, gears, diffrentials, upgrade from stock e for the front and rear and where could i find some at. and how would i find out what kind of gears and stuff im running now and transfer case.

 

[Resto]

Try www.ringpinion.com They have all sorts of gears and axels to have a look at and get some ideas. They even have a calculator where you can calculate what gears you want for your application. Enter in your stock tire size, gear ratio and pick a speed.......the calculator will return an rpm......then stick in the new tire size, the same speed and guess a gear ratio. Keep trying until you hit an rpm close to stock. This will give her that original feeling, even though those tires are way bigger. If you want more bottom end power, pick a gear ratio that gives you a higher rpm and obviously vise versa for more top end.

Give it a shot and play around with it....It helped me pick my gear ratio.

I found out stock information simply by searching the internet. My 78 bronco came with 3.5 gears and I figure a 30 inch tire was a good guess.

 

[79bigbronco]

If you look on the tag on the frt. diff cover bolts the first set of # will be the ratio, prolly will be 3.50:1, some broncos came stock with 4.10,s also. In that case it would say 4.09. For your tire size a set of 4.56's would give you close to stock gearing, a set of 4.88,s will give you more grunt for climbing and crawling. Your tire size will put alot of stress on a 1/2 ton drive line, and depending on your engine,s HP/torque, and your driving style, you may want to consider going to a dana 60/70 combo. I have been having drive line issues myself, since putting in my 429, and I'm only on 35's.

 

[Big0]

Thanks guys