hello everyone!

just purchased a 99 2500 slt and would like to know the proper way to shift into 4x4. The truck didn't come with a owners manual and

i don't want to mess anything up. My only other 4x4 was a 89 s10 blazer and that was shift on fly (or thats what they told me!).

Great forum!! lots of good info!!

thanks for the help

jeff


info on truck

1999 2500 slt laramie w/ auto tranny
5.9 v8

 

Welcome to DF!

You can shift in and out of 4hi on the fly at any speed up to 50mph, though sometimes you have to slip the truck into reverse or turn the wheel to get it to get it to go back into 2wd. I wouldn't recommend doing it while going that fast. I generally don't do it unless I'm driving slower than 30mph.

To shift into or out of 4lo, the truck has to be stopped or moving VERY slow (think idle speed...foot OFF the gas). If you start to get grinding, shut the truck down and then shift the lever after everything has stopped.

It's important to put you truck into 4wd once a month to keep everything loose and the vacuum diaphram from getting hard.

Also, it's important to note that the truck should not be run in 4wd on pavement, except for during the winter. The front shaft and rear shaft are locked together. So when you run it on a hard surface, there's no slippage. Things cand bind or even break.

 

Dodge says you can, but I just can't think of any good reason to shift in/out of 4wd at 50mph. I generally shift between 2hi and 4hi at crawling speed. With the truck in either foward or rev just grab the lever and jerk it one notch. Because of the vacuum CAD thing, at least on mine, there is a slight 1-2 sec delay before the front axle engages and the indicator light comes on. When I shift back out from 4hi to 2hi, i have to let off the gas and allow a moment for the CAD thing to release and the light to go out.

Shifting between 2hi and 4lo is a different story. You MUST be in neutral (or park), stopped or almost stopped, and again, grab the lever and shove it hard 2 notches. Don't pause in the neutral setting, and don't baby it, or else you'll get gear clash and grind.

Like Bruning Rom said, never run 4wd on pavement, because its a solid axle with no rear end type differential thing (technical term) that allows the outside wheel to turn more than the inside wheel during a turn. Without this, the gears/tires bind up and if the tires don't skip easily, then the gears/axles take a beating. You'll feel this in a medium to sharp turn.

One other neat trick. When driving on very rough roads/trails, where I'm going very very slow, I notice that in 2hi, it takes a lot of rpm for the torque converter to catch and move the truck along, especially going uphill. On the other hand, I can shift to 4lo, and with minimum rpm, the tc catches and you just ease along without so much noise and slip. MUCH better for slow speed driving. Enjoy.

 

You don't have to be in neutral or park. I've also found that it's slightly easier to get it into 4lo if you're slowly creeping ahead. You're right though...you have to be quick and hard with the 4lo shift. If you get stuck in N, things are going to grind [&:]

Also, there is a rear end type differential thing The right side tires are differentiated from the left side tires (unless you have a spool or locker). In other words, the right side can turn at different speeds than the left side. BUT, there is no differential in the transfer case, like the old Ramchargers and Power Wagons had. In those trucks, you could run in 4wd all the time, because there was a THIRD differential in the transfer case that allowed the shafts to turn at different speeds. It also made the transfer cases extra heavy [:'(] But the newer Rams don't have that. On the newer trucks, the front driveshaft and rear driveshaft both turn at the same speed. That's where the binding occurs...between the front and the back....not side to side.

 

dang. i hate it when i'm wrong.[sm=boink3.gif]

 

thanks guys. you were right about the 1-2 second delay. works good though!