Transfer Case in my 2008?

[WILL E]

I will do some more web searching but I was wondering what transfer case is in my 2008? It's a 4x4. Full time. With a 4x4 hi and 4x4 low button.



I have to say I was really impressed with the operation in low. I am not new to going off road. I ran a 81 wagoneer with a np208 and locked front and rear. My 'trail rig' is a 82 cherokee with 35" tires, 4.56 gears, and ARB in the back and an aussie up front. I run a second generation atlas 4spd (2.0/2.72/5.44).



So we took the sport trac on a nice forest road. It wasn't rough but the grade was not flat. I left it in full time on the way up. On the way down I pushed the 4x4 low button. It was pretty impressive. First off, when I started down the grade I noticed the transmission stayed in first and the truck just crawled along. Only after applying a little gas was it willing to go a little faster. I tried this a couple of times (stopping completly) and it was consistent in its operation.



But even going down the grade at a little faster speed it seemed to know what was 'right'. I barely used the brakes at all.



Makes me wish I had tried low going up hill as well, but even in auto mode it kept in a good torque/RPM range.



With my cherokee there is a lot more 'messing' with it. I sometimes use 2.0, sometimes 2.72 and for more crazy stuff the 5.44 but you have to know what you are doing. The sport trac made it easy. (This isn't a dig, it's just a fact).



two thumbs up. :banana:

 

[Johnny O]

I forget the model number, but it is not a full-time 4wd transfer case. In 4-Auto it runs in 2wd unless the computer detects wheelspin and kicks in the front axle. If you lock it in 4-Hi or 4-Low then it is in 4wd all the time.

 

[Todd Z]

I also have heard there is a wireing MOD you can do and it will give you a LOW setting. From what i have read its the complete tcase just wired so you dont have a switch for low.



Todd Z

 

[WILL E]

Did some more research and JonnyO is correct. It is not a full time 4wd, most of the time there is no power sent to the front wheels. In 4x4 auto mode the system detects a difference in speed from front to rear and, along with other sensors, determines if and how much power to send to the front.



Onlywhen in 4x4 high and 4x4 low is the split an eve 50% all of the time. Looks like a pretty cool little system.



http://en.wikipedia.org/wiki/ControlTrac



There is a traction control button that will turn traction control off when in auto mode. I wonder if this keeps power from going to the front wheels at all?



Anyways, it's a nice system. From what I found the low range is 2.64. Combine that with the 6 speed 4.17 first gear and you have a very respectable final drive ratio. No wonder it just crawled along as it stayed in first gear.

 

[Yardsale]

Some traction control systems use differential braking to control wheel spin and skidding.