I own a 2004 Grand Cherokee Special Edition. I believe it has the Quadra-Trac II 4-wheel drive system. I do a lot of beach driving and always leave it in "4 ALL TIME" mode. Can someone explain when, if ever, I would switch to the "4 LO" setting? My understanding of this system is that "4 ALL TIME" allows the sensors to determine which wheels need more/less torque depending on tire traction and adjust automatically. I assume 4 LO would lock in the front and rear wheel differentials? If this is wrong, pls correct me and if I am correct, pls tell me when I would use the 4 LO setting vs 4 ALL TIME. Thanks -Mark

Close!

on Quadra-Trac II, the TC uses a Gerotor Clutch Pump to engage the active 4WD, to lock the front and the rear axles together when slippage is felt not to apply more/less power to one wheel or the others, Quadra-Trac II just allows for 2 WD action when 4WD is not needed, then automatically switches when slipping.

Now, Quadra-Drive, Can apply all power to one single wheel on one single axle, kinda like a limited slip where all power is appplied to a free wheelin wheel, except it will apply all power to the one wheel that has the most traction.

4WD LOW - Use this when you are towing on loose/slippery terrain. Not really used anything else.

Yeh, the low gear is like a granny gear. very slow, does not allow for wheel slip. mostly used when stuck in mudd to get traction with out the wheel spin.