Most 2nd gen didn't come with locking front differential, am I right? How hard is it to swap one in?

 

I don't believe any of them did.

If you can find a unit for the D60 it should be as simple as swapping out the pumpkin, however driveability will suffer.

Most guys I know ran an ARB Airlocker in the front so it wouldn't be locked in all the time in 4X4.

 

So our trucks are true 4x4 not 4x3 ie only one of the front wheels is powered?

 

Yes, they are pretty much 4X3 with a stock front dif and working limited slip in the rear.

This is a lot easier on steering components, too!

With the ARB you can lock in the front diff in 4x4 to have both front tires turning. This is handy when you are in a good stuck situation and can crawl out with both fronts pulling. Otherwise you run it in standard open config 4x4, which is really 4x3 with a limited slip.

With a limited slip or full time locking rear end you get the rears assisting too.

 

Not sure if I'd want to have on-board compressor just for the locker. What are LSD options for the front differential?

 

None unless you disable the CAD unit.

But get out your wallet, because if you are serious about a locker up front, you'd want to consider the benefits of bumping up to 35 spline axles to replace the 32 spline shafts. And the Dodge front in our trucks is enough of a POS that I'd pause before putting too much effort into it anyhow. Inside out balljoints, unitized bearings, funky short steering links.

If you have to ask this question in the first place, I'd advise you to forget about the front axle, and either put a posi or locker in the rear. This is where you want it first anyhow. If you just GOTTA have more traction after that, THEN consider the front axle.

A posi is fine for on road, and will help a bit offroad, but if you really want some traction and are willing to sacrifice some handling, get a locker. The locker installation on the rear is STOOPID easy compared to the front, and the d70u in auto srw's has 32 spline axles, but that's really easy to change when you get your new 35 spline locker.

A lunchbox locker you don't even have to play with the shims.

With tires on the ground; pull the pan, axleshafts, carrier bearing bolts. Pop out the carrier, blast off the ring gear, slip out the crosspin and pull the gears out. Slip in the locker and put it all back together. The only funky thing is that it might be a bear to get the carrier back in on some trucks-you need a "case spreader" sometimes. Or ease up on the shims.

If you get a full case locker, you will need to get new carrier bearings or pull your old ones off the carrier (press and bearing splitter-have fun!) and probably a "minor install kit" for the shims to shim the backlash on the carrier.

Doing the front is one HECK of a lot harder because there is SO much stuff to take apart to get the axleshafts out so the carrier can come out.

And these trucks are 4wd, they just have open diffs. You only spin a one legger when the torque bias between the sides exceeds 2/3 on one side and the power exceeds said traction. Posi's offset this bias some though.

 

Oh and btw the big thing with getting a locker in the rear is when you cross up the suspension. For instance, when you have your left front and right rear tires stuffed into the fenderwells, the opposite tires have very little pressure on them, and hence very little traction.

So even with a posi, you'll probably start spinning the right front and left rear (one leggers). But if you have a locker in the rear, BOTH your rears will turn unless something actually breaks. So that funky lurching dual one legger thing goes away COMPLETELY. In the mud no one leggers in the rear either is nice, but full case Detroit lockers are sketchy on ice and snow. Lunchbox lockers are better, but handle worse as daily drivers IMO. Pop, clunk, lurch! You get used to it.

Selectables in the rear are very nice though. Turn it off and it handles "normal" and is nicer to u-joints due to not having springloaded "slop" like ratchet lockers.

 

Unless your prepared to upgrade to locking hubs on the front and have very heavy steering while in 4wd, forget a locker.

LSD is nothing special except for a bit of work to install it with regards to pulling axles and unit bearings and such.

If you go the LSD route, you have a choice of a friction (clutch disc type) similar to your factory rear diff and then you have a more aggressive mechanical LSD. I would go with a friction type LSD and know quite a few people with them installed and they have zero problems and go anywhere with there trucks. I know of 2 trucks with mechanical LSD's and they are a little jerky in the steering while driving on snowy roads whereas the friction types drive a little more like a front wheel drive vehicle.....you can feel the "pull" in the steering wheel but it's not over powering.

Gear and carrier work is not to hard to do yourself but for the extra few bucks involved, pay a gear shop to do it, you will be ahead in the end. By the time you pull bearings and shims, set it all back up and just over all chase your tail a bit, it's not even a one day job for a pro shop.

Jeff

 

HUH! A locker is just that, it locks the two wheels together. In a situation like you describe, both rear wheels will still drive. In the same situation with a LSD diff, yes the unloaded wheel will most likely spin but there will still be bias to the "stuffed" side and that wheel will have torque applied to it unless the LSD is worn out.

The same situation with a locker in both diffs, the "stuffed" wheels will have torque applied to them just as the "unstuffed" side, hence true 4wd.

Jeff

 

Been researching a bit and came across this site
http://4wheelonline.com/Products.asp...ProductId=1855
Seems like good prices, what do you guys think.

 

+1, but I *think* what your buddies might have with a "mechanical LSD" sounds like a locker.

I'll elaborate;

Clutchpack posi:
side gears have plates and friction discs behind them to add friction to prevent wheel spin. Preload springs engage them, and spider gear/sidegear deflection locks them in tighter. Trac-loc, Powerlock, Powerbrute and the like

Cone type posi:
similar to clutchpack, but single cone friction to metal to add traction bias. Auburn gear.

All gear posi:
No side or spider gears, worm gears drive other gears. The basic principle is that a worm gear can turn a ring gear, but a ring gear cannot turn a worm gear. These are SEAMLESS. Very invisible traction device. No special oils. Where clutchpack posis hold then slip, these slip then hold as wheel spin increases. True trac, gleisen/torsen type Still just a posi.

Full case locker:
Detroit. Other manufacturers are making them now, but for DECADES they were the only full case ratchet locker. Yukon is making them now too. STOUT springs drive the carrier. If one side is wound up, it disengages one side to let a wheel travel at a different speed. This windup is what causes the soil yourself loss of traction on ice. This is a LOCKER NOT A POSI.

Lunchbox locker:
This is a true locker. VERY VERY VERY easy to install compared to any other traction device. No adjustments required. Plug and play... well as much as can be with major drivetrain components, anyhow. It replaces the spider and often (though not always) the side gears. There are no preload springs, so there is no soil yourself "release" on ice, but this means there is slop back and forth. Pop, hiccup, clunk. Lock Right, Detroit EZ locker Aussie locker etc.

Last are the SOOPER DOOPER selectable lockers:
Conventional differential, except for a mechanism to lock the diff gears up making it go from grocery getter to racing spool with the flip of a switch. A few are posi when open, too. Usually put in front (oops!) much more appropriate in the rear where you can benefit from the smooth highway handling when unlocked. Eaton E-locker, ARB air locker, etc.

 

Great replies so far. Usually I see these differential threads with so much misinformation already thrown around.

The one thing I can add to all that great advice is that even though it "can" be done.....its highly suggested NOT to run a limited slip or locker in the front unless its a selectable locker. Its very dangerous to run one in the front on low traction "on road" surfaces (like snow or ice) and will most likely result in you ending up in the ditch or in an accident. Definitely not what you'd expect from running 4wd.

Also, a limited slip is a horrible carrier to run in any situation where one tire would be off the ground. They just dont have enough break away pressure to hold the applied torque and therefor result in the tire off the ground to spin. This is where lockers shine and are meant to be. Although running a locker on a truck used to tow heavy can also be not such a good idea. They're just to harsh on the drivetrain and the added weight of the trailer stops any cushion the tires gave the locker.

The OEM limited slip units can work great too but have a low break away pressure for the most optimum street safety but its also very common for someone not to understand the basic principles of a limited slips working unless they've purchased an aftermarket unit, so OEM limited slips tend to be quickly abused and worn out not by neglect but ignorance. Usually by performing one tire burn outs, running two different size tires on the same axle, or running the small spare tire. The later two I just said will destroy a limited slip in about 10 miles too.

 

Just had my rear diff. rebuilt and had them put in a Detroit locker. I was up in the mountains middle of the month and the difference it made was amazing when climbing around on trails or pulling people out. Will have to see what happens on the ice though!

 

A traction control device can be a MAJOR benefit up front. But there can be some really bad drawbacks, and I should have gone over that, but the only one that is a really big NO NO in the front is the Detroit full case.

Our trucks with Center Axle Disconnect CANNOT (I REPEAT CANNOT) run anything but a selectable unless the CAD is disabled. Otherwise the locker will ratchet constantly, or the posi will burn up.

So you don't want a full case Detroit up front unless you have manual hubs and unlock them. This is because the preload springs wind up and when they release (even in 2wd) the tires tend to spin out. This is friggin DAAAANGEROUS! Not too bad on dry pavement, but in corners on slick pavement front spinout BAAAD MOJO!!!

However, a posi up front is nearly invisible 2wd OR 4wd, and lunchbox lockers are virtually invisible in 2wd. I drive my Samurai with lockers front and rear and NEVER unlock the hubs. The only strange thing about driving with a lunchbox locker in the front is if you panic stop in 2wd and lock only one front tire up. Suddenly you hear one side of the locker ratcheting REALLY fast. Not dangerous, not even to the locker. Just sounds strange.

Lunchbox lockers in the front when in 4x4 have a tendency to try to steer you one way or the other in reverse, and make steering very heavy in certain circumstances, but the traction... well it's unbelievable.

High speed 4x4 offroad driving is funky with a locker up front. Posi is great, open fine, spool or selectable up front, not bad. With a ratchet locker (especially lunchbox) you'll probably decide to leave it in 2wd going 30 on fire roads.

 

Good prices, those are clutchpack type positractions.

I'll note that positractions aren't too uncommon in the rears of our trucks. Mine came stock with one. Make sure yours doesn't!

Two other notes that are somewhat important. First, is that if you already HAVE a positraction, it is usually possible to "shim" the preload springs to really tighten it up. This is a basically FREE mod, and you might be happy with it. Posis that have coil spring preload springs (clearly visible with the diff cover off) can just be shimmed with washers. Others get trickier.

Secondly, if you are unhappy with the traction you have now, you may be VERY unhappy with a positraction. Often folks expect more from a posi than it can deliver and should have gotten a locker.


Reread m.rhme's post. That's typical of a customer locker review.