Shift on the fly 4WD (96-98 SR5)

[dursman]

Hi everybody. First post here, just want to say hello and I have some questions. I'm about to buy a 3rd gen 4Runner and I had a few questions about the 4WD. I know on the Limiteds there is a button on the side of the 4H/4L/N lever which allows you to shift into 4WD while driving, but my question is... on regular SR5's there is no button. Can I still shift into 4WD while driving by just moving the lever into 4H? I'm assuming I have to be stopped and in neutral to go into 4L, but 4H is what I'm more concerned about.

When the lever is on 4H or the button is pressed can I drive on dry pavement, or is that only with the "multi-mode 4WD" on the 99/00 Limiteds?

Any help would be appreciated. This forum has given me tons of info already. Thanks!

 

[Del34]

I think the manual says you should be going 25 or slower to switch from 2L to 4H. But I'm sure if you were going a little faster, it'd be fine.

You can shift back to 2L at any speed.

But yeah, if you want to switch to 4L, you have to be in neutral.

 

[Lexusbstrdchild]

and yeah you can drive in 4wd on dry pavement, although with today's gas prices i wouldnt suggest it!

 

[lee]

what i understood was with the push button 4wd in limited and 01+ sr5s, we can drive on dry pavement.

but you dont want to do that with older sr5's (like the system you have). and DONT take sharp turns!

 

[pat161]

Good questions, so heres some answers. 96-98 had a part time 4wd system with ADD, aka shift on the fly 4wd. You can shift between 2h and 4h while moving, someone said 25mph. I checked my owners manual and it states w/ the lever style 4wd selector and auto or manual w/o ADD you should be 25 mph or less, w/ the add it says it is acceptable to go 50 mph or less. I believe the first instance means if you have manual hubs which no 3rd gen runners do, so therefore 50mph or less should be the number you're looking for. As for the sytem it is a part time system w/o a center diff., meaning it is a bad idea to use 4wd on dry pavement as your driveline may bind around corners. If you want full time 4wd you need the multi mode system as you stated.

 

[Lexusbstrdchild]

i guess im confused too. what would the difference be between driving on dry pavement vs driving in snow. i mean as far as having the driveline bind up. i mean a corner is a corner right? so if youre turning, what why would dry pavement make it bind and snow would not. im just asking im not flaming anyone.

 

[lee]

speed & traction. both of which cause terrible binding. in a turn, the tires are turning at different speeds and rates, so if you have more traction then you have more tight binding.

in my push button 4wd, the corners dont matter so much though... i think you have that too in your limited.

 

[pat161]

It's the traditional 4wd that will bind around corners on dry pavement. The idea is that when you have one front tire and the opposite rear tire spinning with power, around a corner they will naturally need to turn at different speeds. Meaning the inside tire travels less distance than the outside tire and thus spins slower. Normally your diff allows for some slippages between two wheels on the same axle, so they can spin at different speeds. In a traditional 4wd there is nothing to allow for slippage between the front and back axles, so as you go around the corners both drive wheels are forced to spin at the same speed, this is what causes the binding, in snow or any other slippery condition it is no problem because it is easy for the faster turning tire to slip, so it doesn't bind up. The center diff in newer runners allows for slippages between front and rear axles.

 

[Lexusbstrdchild]

ahhhh ok. makes sense now!