Originally Posted by DBL Boost
if I'm in 4x4 low auto is it only 3x4 or is it true 4x4?
Neither. It's a 2x4..... that's it. You have an open front and in your case an open rear differential. You will get power to the tire with the least resistance on both the front of the truck and in the rear. There is no mechanical lockers/limited slips in either of your diffs so that's the best you get. I mean you have "4wd" regardless of 4hi or 4lo but that just means the transfer case is sending power to both the front and rear diffs. If you had the E locker in the rear, provided you engaged it you have both rear tires mechanically locked and then still just one of the two up front giving you a 3X4 I guess lol. But you don't have that.
The rear will still have the electronic limited slip... which is nothing more than the ABS pulsing the rear brakes to try and keep the wheel speed equal. That's it.
So put one rear and one front tire on sheer ice and the other 2 on dry pavement. Other than the pulsation of the rear brakes trying to transfer power to the rear tire on pavement you would just spin the front and rear tires that were on ice and not move. Because of the rear brakes acting as a limited slip in theory it should get you going.... but I can tell you right now either of my trucks easily overcome that brake limited slip and just spin one tire.