95 f250 4wd 5.0 zf transmission. It has 3.55LS, but the LS doesn't seem to do much. It spins one wheel on slippery surface. Thinking of adding a locker. Maybe air locker so I can turn it off normally. Are these reliable? Hard to install?

 

I would double check that you have a limited slip. put the back end on jack stands and spin a tire and see what direction the other turns. air and electric lockers generally go up front and they are not hard to install but you need some specialty tools and need to be very precise setting things up or it will get chewed to hell very fast

 

Selectable lockers are often used in the front, that's true. But that's mostly because it's so nasty driving an auto locker in the front that people will pay more for a selectable there, while they will more often choose to save a couple hundred buck and run an automatic locker in the rear.

I have heard one person claim that the ARB is junk, and if it is marginal I could see it being more likely to break in a rear axle. But most people seem to think ARBs are good quality units, and if most people are right, then it really shouldn't be an issue.

Are selectable lockers easy to install? The simple answer is "no." It requires setting up the ring and pinion gears. That's not rocket science, but it's one of those "if you have to ask you probably can't do it" sort of things. If you want to do it yourself, look up instructions on-line. You can decide if you're willing to buy the tools required and if you have the patience and skills required. Otherwise you need to take it in to a shop.

 

Hmmm. Then maybe I should have the LS rebuilt and get a locker for the front. It seems like electric locker would be easier to install than air?

 

Electric and air lockers will bother require setting up the ring & pinion gears, no advantage to either one there. An electric locker requires running wires to the diff. An air locker requires running air lines. 'Bout the same either way there too.

An air locker does require mounting, wiring and plumbing an air compressor (as well as buying it). The wiring probably isn't too much worse than wiring an e-locker, but the rest is definitely more work to do an air locker. 'course the advantage is then you also have on-board air, so you do get something for the extra effort.

I know there are quite a few people that are pretty happy with friction-type limited slips, but personally I wouldn't put any effort or money into one. If it were me I'd put either some type of locker in the rear, or maybe a True Trac gear-type limited slip. Having said that, I'm sure there will be people telling you that rebuilding your current LS is cheaper (and they're probably right) and that it will give you all you need. And they may or may not be right about that. It depends on what you need..

 

I don't know if you have looked into the price of an ARB or ox electric locker but they are pricey. Be ready to drop $1500 on locker and install. The Lsd works pretty good especially if you rebuild it tighter with an extra plate or 2

If you do buy a locker I would like dibs on your Lsd

 

A Detroit Locker can be had a lot cheaper than a selectable locker. Think I paid about $550 for mine. Installing would only require a backlash and pattern check, not full gear set up.

 

I've never set up gears myself, but my understanding is that a backlash and pattern check essentially is a full gear set up. If you are re-using your existing gears there's a reasonable chance that you'll hit it right simply by using the same shims / settings that it had before, and the backlash and pattern check is to verify that you're still in the right place. But if those checks don't show you what you want, then you're back into the full gear set up process.

 

The bad thing about the Detroit besides the tire barking in the corners is that it will kill you if you have ice an snow where you live. It will lock an unlock and throw you sideways in a heart beat. Besides that its a great locker an so are some of the other lunchbox lockers like lok right

 

I have a 94 ford f150 with yokon grizzly lockers front and rear thy have a life time warranty and are great in mud and snow

 

A 'full gear set up" would be done only if you were changing to a different gear ratio. A "check" is just that, checking the pattern by painting the gears with grease and rotating to read the pattern. The pattern is influenced the most, by the pinion gear depth in the housing. You don't have to remove the pinion gear from the housing in order to change the diff. So, pinion depth doesn't change when changing differentials. The backlash is set by side shims at the diff. So, changing the diff only effects the backlash. Bolt the ring gear to the diff, set/check backlash, set diff bearing pre load and a pattern check is done of course just to be sure things are still good.

 

Something you may want to try and it's a whole lot cheaper than anything else is to simply change your diff fluid. Use one specifically for the LSD. You may be surprised that after you change the fluid your LSD starts working quite well. I've seen many LSD's that had the wrong fluid in them.

 

On a similar thought...I think I put too much friction modifier in during my last change.

 

I have a 99 SD and have a true trac in the front, and a detroit in the rear. Love them both, Yes you have to careful ion rain or snow as the *** end tends to kick out on ya, to avoid it I lock the front hubs and use the four wheel drive, it's a different truck with all that traction, night and day. and alot cheaper than the e-locker or ARB. and you dont have to do all the custom work for the air line or wires, just something else to get hung up on and get ripped apart, than you have no locker.

 

Well, that doesn't sound to good to me. Sideways is not good. I also thought about changing the fluid like others suggested. Maybe will try that first, but also thought about going to 4.10 ratio or somewhere around there. Going to put 35" General Grabbers on it and want to do everything at same time to save labor. If I do locker work at the same time as I change the ratio, am I avoiding any rework and labor that way?