I have a automatic 99 Xj, On the shifting console, there are 2 modes that I dont know what they do. What are the 3 mode and 12 mode used for? Thanks.

 

3 keeps it from going into 4th gear. In 3 the torque converter will still lock.

In 1-2, you can use gears 1 and 2. The shift from 1st gear to 2nd gear is at 4000rpms.

 

How does shifting into them work in a mechanical sense, if you know?
Can I shift into either while driving, and does moving over R cause any unwanted.. Reverse "action"?
If you can shift between then, do you still need to apply the brake to shift?

 

 

No you don't have to apply the brake to shift between D, 3 and 1-2. If you are shifting over R you are going into park, which you shouldn't do while driving.

 

Thank you, I was simply wondering what kind of procedure would be needed to shift into these when driving, and if there are any dont's about doing it.
I already knew the R and Park thing, I'd like to keep my transmission xD

 

Shifting into 3 while driving isn't a big deal, its basically the same thing as kickdown when you heavy accelerate except you are controlling when it down shifts instead of throttle position and rpms. When I ran trails in my old jeep I would run in the 1-2 range. Helps keep the rpms up while keeping a lower gear. I wouldn't recommend dropping into 1-2 st higher speeds.

 

I never knew driving an auto. might be so difficult