I'm doing work on my 8.8 Bronco rear end and I want to put in a locker. it currently has the original 3.55 gears and I was just wondering if I have to have both gears and a locker or just one or the other, because I was also looking at putting in 4.10 gears but wasn't sure weather i need to put in both or with a locker act as the gears? I am confused on how it works please help.

P.S. does anyone know how many splines my rear end has? it's an 85 Bronco with an 8.8, all original rear end. I know its either 31 or 28 and am just hoping I can find out without taking it apart and counting lol. thanks

 

You might have better luck in the trans and rear forum down the page further.

 

Switching from one ratio to another, you need to change the gears in both the front and rear axles if you intend to use it in 4wd.

The locker has nothing to do with the gear changing. You can put the locker in either axle. In my opinion it is better to have the locker in the rear. When you change the gears, that is the best time to put the locker in.

Your axle likely has 31 splines but the only way to know for sure is to pull the shaft and count them. It is not hard to pull the shaft though. Remove wheel, remove drum, remove brake hardware, remove backing plate and axle retainer plate, and pull the shaft .