Gears

Alrebel_09 · Post by **Alrebel_09** » Fri Dec 22, 2006 1:47 pm

My 86 bronco II has something like 3.42 gears. I was going to replace them with either 4.11s or 4.56s. On the Precision Gear website it says When replacing a 3.45 and numerically lower ratio gear set with a 3.73 or higher gear, the case must be changed to a 3.73 and higher case. Is there any way to get around this or do i have to change the case.
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ranger5.0 · Post by **ranger5.0** » Fri Dec 22, 2006 7:58 pm

You just have to change the carrier not the axle housing.

Bob Myers · Post by **Bob Myers** » Sat Dec 23, 2006 8:40 am

Interesting.
When I had the 7.5 and Dan28 in my Bronco I went from the 3.54 gears to 4.1 without changing carriers.

Phillippi · Post by **Phillippi** » Sat Dec 23, 2006 1:41 pm

I went from 3.73 to 4.56 without a new carrier.

84_4x4 · Post by **84_4x4** » Sat Dec 23, 2006 8:33 pm

im wanting to run 31x10.5/15s on mine pretty soon will i need to change gears and if so what will i need to run and where can i buy them and how do i put them in

Bob Myers · Post by **Bob Myers** » Sun Dec 24, 2006 6:45 am

either a 31 or 32 would act just like stock gearing and stock tires with a 4.10 gear. I had stock 235/75-15 and 3.45 gears, went to a 32" tire and 4.10 gears and the speedo was actually closer to right than it was stock.
I would check ebay for the gears, any reputable shop can install them. Depending on how far away you are we could do it at my place, in Lexington

84_4x4 · Post by **84_4x4** » Sun Dec 24, 2006 11:56 pm

what do i need to keep in mind when looking for gears so i get the right ones and im only bout 2 hour away so some pro help would be much appreciated in future

Bob Myers · Post by **Bob Myers** » Mon Dec 25, 2006 7:07 am

I am presuming that you have a stock BroncoII, it will have a 7.5 in the rear and a Dana 28 in front As long as you buy the gears for those you will be OK. There is a guy on the UCORA.com board and also RRORC.com board that did have a set of gears, unknown as to whether he still has them. His screen name on both boards is; g.l. frederick. He lives in Louisville, his son (Steellfish on the NAXJA board)owns a 4x4 shop out on Dixie Hiway.

Happy_Jack · Post by **Happy_Jack** » Thu Dec 28, 2006 3:04 pm

Dana splits the gear ratios with two different carriers. Ford dose not. So no need to change the carrier in the rear. The front is another story. For a Dana 28 TTB the break is at 3.73 and higher numerically (4.11, 4.56, ect..).

Maybe some of the confusion is because other Dana axles split at different ratio's. Dana 35 (in some 90 BII's) 3.54 and numerically higher. Dana 44 TTB in the full size Bronco and F-150 3.92 and numerically higher.

I saw in the past in one of my speed parts catalogs where they made "thick" ring gear sets to solve the problen of changing the carrier. Never saw these made for our little truck though. Just have to replace the carrier.

Just to explain what I mean by carrier. The carrier is what the ring gear bolts to. It is what the side bearings are pressed on to. The third member or chunk is the cast aluminum housing that the carrier and pinion are installed in. Then the third member is bolted the drivers side Twin Traction beam.

Hope this helps. Good luck.