The91XJ

Hey guys, i have a 91 laredo and was wondering what exactly the difference was between the part and full time four wheel drive. Which one would i use for wheeling? and which one would i use for slippery/snowy roads? Thanks

prerunner1982

Part Time is used for Wheeling. It locks the front and rear driveshafts together. The Fulltime is used on the road (dry, wet, slippery, etc).

ck1

not to hijack BUT....if one where to put lockers front and rear how will the full time feature work in snow?...I ask as we get a TON of snow here in so cal (just kidding) but i want to lock my XJ up for the trails but I want to also use it up in the mountains for snow trips...I also have a YJ that is locked front and rear and it is a little hairy in the snow....does the full time feature work any different with lockers then the part ime with lockers???
cameron

gpXJ

My understanding is if you lock both front and rear, then you lose the Full-Time, as the TC will no longer be able to send different amounts of power to each side. That is the difference in FT and PT.....FT you get 48% front, 52% rear, which allows you to turn and drive it on pavement. PT sends it 50/50. Lockers basically make it where there is no choice...50/50 in 4X4 regardless of the setting. Also, on ice...with lockers....don't expect to turn.

prerunner1982

The front locker would still cause the front tires to bind/chirp when turning regardless of tcase setting. However, adding lockers both front and rear to me... defeats the purpose of a fulltime tcase. The tires on each axle spin at same rate, if one hits dry pavement and one hits ice they still turn at the same rate. The point of a Fulltime tcase is to allow the vehicle to transition between dry and slick conditions without jolting the drivetrain. This is done by differentials in each axle and in the tcase.

tkdtim

I dont think the Full time vs full time really has a power split, but I could be wrong.

My understanding is that the Full time (242) has an extra component inside that acts like a center differential and allows the front axle to turn at a different speed than the rear.

The Part Time (231) does not have this component thus both axles (front and rear) are locked at the same rate of turn which causes binding and damage when cornering and the front wheels are not allowed to slip or go a different speed when they need to.

xjod

I have a 242 t-case, I had mine locked front and rear until last march. The full time option does have a small torque split(55/45 I think) but, with a locker on the front you lose the ability to turn well when the front wheels are powered. Deep snow is fine, plowed roads are dangerous with a front locker in 4WD. If you want a locker on the front and plan to drive in the snow, most people as well as myself would recommend a selectable locker on the front.