Front and rear Spartan locker review
 

I know these lockers have been reviewed many times but I figured I'd put in my .02 so here it goes.
I installed the front locker first, it wasn't that difficult and the nice thing about the front is you can install the locker with the carrier out of the vehicle. I had to pull the ring gear off to get the center pin out but it wasn't that big of a deal. I put red locktite on the ring gear bolts and torqued them to 55 ft lbs, installed the carrier and torqued the bearing caps to 60 ft lbs, then put everything else back together and filled with 85-140 gear oil. I tested it out in a muddy, flooded field and some hill climbs and trails. The front locker doesn't seem to affect the steering at all when in 4x4 there is slightly more resistance in the steering wheel when making sharp turns and it returns to center quicker than it used to but if you didn't know it was there you wouldn't be able to tell the difference between that and an open front. At first I thought it may not be working right because I expected the steering to be much stiffer and harder to turn from reading other reviews but thats not the case. I even tested it by putting one front tire on a jack stand and jacking the rear up slightly so only one front tire was on the ground, as soon as I put it in 4x4 it pulled me right off of the jack stand. On the street the front locker is hardly noticeable the only time you can hear it is when you make a real sharp turn and you can hear it clicking, it basicly sounds like a bad u-joint.

A few days after installing and testing the front locker I installed the rear. Since I had the factory limited slip I had to install a open carrier first so I could put the locker in. I picked up a used carrier and installed new carrier bearings and races on it, swapped the ring gear over and torqued the ring gear bolts to 55 ft lbs with red locktite and put the carrier in. I made the two adjuster tools for the side adjusters with two 30" pieces of 1/2" black iron pipe with a 36 mm nut welded to one end and a 9/16" bolt on the other I had two people on each side turn the adjusters while I measured the backlash I got it set to .009" and torqued the bearing caps to 60 ft lbs and rotated the carrier a few turns to seat the bearings and checked the backlash again it was still within spec.

Installing the locker into the carrier at this point was not that difficult at all, I had some trouble getting the passenger side C clip in and seated but I finally got it. I put the cover back on and filled the rear with 85-140 also. The rear locker does great off road as expected but I haven't done much real offroading yet since I installed the lockers. On the street the rear locker does great it doesn't push the vehicle around or make it "change lanes unexpectedly" as some other reviews have stated. My jeep is an automatic so it may be slightly different than a manual would be, I had it up to 75 on the interstate and got on and off of the throttle a few times to see if it would lock/unlock or cause it to pull to one side but it never did. When making sharp turns you can hear it ratcheting but it isn't loud at all, you can make it lock up and chirp the tires if you give it enough gas but if you drive normally it unlocks like it should.

Overall so far I am very happy with both Spartan lockers on and off road, and I highly recommend them. I am not going to start the debate on which end to lock if you can only do one but on a street driven vehicle I would recommend locking the rear so you get the added traction all the time. However If you already have a working limited slip in the rear like I did then you may get more benefit by locking the front. If anyone has any questions about the install or operation of the lockers I would be happy to answer them.

Nice review. Been thinking about Spartans myself. You can find good or bad reviews for anything if search long enough. Glad they are working for you and appreciate your open and honest review.

Happy Jeepin'

Nice review. I noticed you have the NP 242. Just curious, when you had it in 4wd, which setting was it on? full time or part time? I would be curious to know how it does in full time 4wd in the snow -I guess maybe you will find out next winter.

Part time I never use full time. The only time I have used full time was just to see how it works.

Thanks for the reply. You don't see reviews for a front locker with the 242 very often.

*Update* I have gotten the chance to put some miles on these lockers and do some more offroading. The rear locker has quieted down even more and the only time I ever notice it on the street is if I accelerate hard around a sharp turn it will chirp the inside tire, the front locker only makes noise when going real slow and turning sharply on pavement, I have also driven in the rain many times with no issues. Off road having the front and rear locked is amazing, I can climb stuff now that I wouldn't even attempt before. I haven't even came close to getting stuck yet but if I do I hope it is in a place where someone else can get in to get me out. I am still highly satisfied with the Spartan lockers.

I have these installed front and rear as well.

Very happy so far. They make a HUGE difference. Yes, I would like selectables. No, I don't need them yet, LOL...and selectables won't happen until one tons anyways, haha

Spartans have fit the bill nicely so far. Happy with the purchase and their performance.

A selectable would be ok in the front but I wouldn't want one in the rear, the idea of paying $900 to have an open rear on the street doesn't sound good to me. I have about $750 total in the Spartans and that includes both lockers, an open carrier for the rear, new rear carrier bearings, two lube locker gaskets, and gear oil. That is less than the price of one selectable locker not a bad deal if you ask me.

I have one in the front (the rear is welded) & have noticed on a downhill decent the steering is terrible. I'm guessing that the weight of the XJ is causing it to bind up. I usually throw it in 2wd to be able to steer easier.
It is totally invisible in 2wd.

Not a bad deal at all, but selectable out back is better on road than a lunchbox hands down. Up front isn't as picky as it's only engaged when in 4wd. Out back is a different story, as anyone here with a lunchbox can attest to...take a corner a bit too quick, and it will pop and bang...just pull into any parking space a bit quick and you'll be reminded you have a mechanical locker, haha...

There is a learning curve to driving with one...but once you get it, you never know it's there, until you get a tad generous on the skinny pedal, LOL

4WD is horrible, unless you're in dirt, and even then it sucks...haha

But get it in the rocks, and it's happy...at least mine is

Off topic but a shout out to Big D

Thanks for the rear disc conversion...been running it for a while now, and zero complaints. So thanks for providing a great mod at a low cost. You rock.

:head:

Thank you. Really glad you are happy with the conversion.

I am usually on the rocks.
I had a lunchbox in my old 8.25 but removed it after only a few weeks due to the erratic behavior on back roads. It was like I was driving on ice. Scary stuff.
My 8.8 is welded & predictable as the sunrise. No rear sway when in or out of the throttle. Tire wear is not noticeable.

Huh. My rear Spartan is predictable as the sun. Never there until you gun it or take corners too quick.

I've known folks with the welded spiders, and every time they turned a corner on the street, CHIRP-CHIRP-CHIRP, LOL

Hey, whatever works for ya, right?

My rear Spartan is hardly noticeable on the street. I even let my dad borrow the jeep for a day while I worked on his car at my house and I didn't tell him anything about it having lockers. He didn't notice it at all.