Rear LSD was available from the start of Grands in the '93 ZJ's, and I believe it's still an option on the WK2's.

In 1999, Jeep introduced the WJ Grand Cherokee with the all new Quadra-Drive system. It consisted of front and rear Vari-Lock axles (hydraulic limited slips operated by a gerotor pump), 3.73 gears, and the NV247 transfer case. It's still considered one of the "ultimate" AWD systems.

 

I dont understand it. What is the point of "Full time 4WD" if you have "Part time 4WD"? Once you put the shifter in 4WD, its there until you shift it out.

 

That's a jeep thing purpl.... "Full Time" left an open differential in the t-case, so, you could still use it on dry pavement. Great for patchy snow, and such. The "Part Time" is what most folks would consider "Real" four wheel drive, with the transfer case splitting power 50/50 front/rear, with NO capability for differentiation between the two. Recipe for broken parts on dry pavement.

 

Oh, okay i get it. "Full Time" 4WD is for people who dont know how to drive in light snow.

I know my mom's '07 4Runner has a limited slip center differential that you can switch between open and limited slip. Let me say that it will go through anything in the winter (except ice, already tried that and ended in our ditch ).

 

No, full time is for when the roads are questionable, but not bad enough for 4 part time. If you've ever tried making a turn in 4 part time on anything but loose dirt/gravel, or snow, you'd realize why full time is such a neat thing.

Many people look down on full time cases because they aren't "real" 4wd, especially the NP249 and NV247's found in Grand Cherokees that don't offer a 2wd option.

I build 231's, 242's, and 249's and can tell you first hand that the 249 is the most simple and strongest out of the 3 cases, with the 231 at a close second and the 242 third. It has the widest chain, and the least amount of moving parts. I feel this would be an amazing swap for a 2nd gen ram, assuming the donor is the revised '96+ version. You can pick one up practically free because most ZJ guys toss them to the side for a 231 or 242 when the VC locks up, or just because they want 2wd. Slap a new VC in and maybe do a complete rebuild if you feel like it, then have a great full time 4wd system, a 2wd option via the CAD system, AND still have the ability to lock the axles together in 4 low.

I had a 249 in my ZJ until I swapped it out for a 231. I miss every couple of days after some snow hits when the plows have gone through leaving patches of snow/ice and pavement. Shifting in and out of 4 part time isn't that difficult but it's kind of annoying.

 

I guess i've never been on a "Questionable" road before then. Because if its okay, I'll take my chances in 2WD.

 

People have different definitions of what constitutes a "real" 4x4 as well..... for me, it was always "a two speed transfer case"..... My old blazer had the NP203. (yes, that great cast iron pig of a t-case, that I couldn't break even if I HAD tried.) I hated having to drop that thing. It was HEAVY.

 

i had a mid 1960's model dodge with the transfer case you are talking about. it had a differential built in. it also had two locking levers. it was great. theft proof too. it was automatic , but, had three levers on the floor. all i had to do was put t case in neutral to keep morons from driving it off !!! sadly, my 1999 ram can not be run on dry pavement, makes a lot of work in patchy snow/ ice.

 

No kidding, hydraulic? Badass. So are the limited slips constantly "locked" in all the time, or only in low range? It just seams to me like front and rear limited slips for daily driving in the snow would be a bad idea... very squirly.

Thanks for the informative post!

 

My Father just Bought an 05 for my mother for Christmas....A guy brought in into his shop barley running , my father told him it wasn't going to last and that a connecting rod sounded bent. The guy offered to sell it cheap....so my father agreed to purchase it the next day ...then guy called him back 20 mins later when the engine shat the bed on the way home......so the price dove even lower. He paid the man , towed it home, rebuilt it and now he has a sweet fully loaded overland for about $5000 total. Pretty good deal ! My mom has wanted a Jeep since my wife and I bought our JK. I wish I could have got the deal he got .