I have a 1975 Ford f250 4x4 with a Dana 60 4.10 open differential. I'd like to upgrade it to a limited slip but don't know too much about gearing. With that said I'm planning on having a local shop do the install, but would like to save some money and purchase the parts beforehand.

Summit Racing/jegs/Google return a whole bunch of results that I don't fully understand. Anyone able to point me in the direction of a reliable limited slip that would work for my setup? I don't fully understand all/what parts I will need.

Thanks

 

This place offers a variety of limited slip differentials for the Dana 60 in one page so you can see all the choices and prices:

https://www.justdifferentials.com/category-s/2702.htm

The most basic LSD is the clutch type. There are clutch plates that can lock the two sides together using the side forces generated by the spider pinion gears (mounted on the inside diameter of the ring gear) when they push against the side gears that drive the axle shafts. They usually come with a preload spring that applies a little pressure on the clutches all the time in case you ever get one wheel completely free spinning, some torque is applied to the other wheel, which presumably has more traction. Since they engage by sideload forces, if you make a turn under power, the clutches will try to engage, and you will have to force slippage between them. This is usually done with a friction modifier in the gear lube to make it slipperier. Eaton's version of the clutch differential is trade named Positraction, but everybody uses that name like "Kleenex".

There is the brute force locker type which uses spring loaded gears on each axle that locks the two axles together. When you make turns, the differences in axle speed cause the two axles to bind up, and when the forces overcome the spring pressure, they pop open, allowing the axles to turn at different speeds for a moment before the gear engage again. Not advisable on the front end.

The more sophisticated types are variations on the original Torsen type differential, which used worm gears and worm wheels that connect the two sides together. The pitch of the teeth on the worm gear and the worm wheel can transfer up to 4X the torque from the side with less traction to the side with more traction when it's on a low traction surface. It's technically still an open differential, as nothing really locks the two sides together, so if one side has zero traction, it can spin freely. But when you get into those conditions with these types of differential, you can gently apply the parking brakes to get out of them. This type includes the original Torsen and helical gear types like Detroit TruTrac or Speedmaster Torque Worm.

Then there are the active types like an air or electric locker that you push a button to lock the two sides on-demand.

Other more exotic types include gear-rotor activated clutches, or viscous fluid couplings, but I don't know if they're readily available.

You can decide what works best for your application.