Switching From 2wd to 4wd Constantly

Driving on a bunch of different road conditions, I switch from 2wd to 4wd a few times each time a drive. It'll be clear on the highway and main roads, but icy in side streets and parking lots.

I worry about messing up the 4wd while driving on dry, paved roads (I don't know why it makes a difference? Just read it in the manual).

Then again, I'm worried that I'm killing the heck out of the 4wd drive button and that if I keep using it a lot, then it'll wear down quicker.

All that switching got me thinking... What's better - switching 2wd to 4wd and back again a few times each time I drive, or keeping 4wd on all the time, even on dry, paved roads for short distances?"

 

Never ever drive with 4wd engaged on dry surfaces (especially curves/turns) I figured this would be common sense.

 

Lots of different opinions on this. Personally, i only engage 4WD offroad where slippage is possible and on paved roads covered with snow/ice... never on dry pavement. If your constantly going through snow/ice to dry conditions engage the 4WD on the longer straight stretches and go back to 2WD in tight turns/parking. Try to use the 4WD as little as possible but don't hesitate if conditions get dangerous. If there's a good chance of damaging the truck or your family get into 4WD if needed...that's why you got it.
Would i constantly switch between 2WD and 4WD?... no.

 

Just drove 300 miles in 4x4 through a snow storm .Once its in 4x4 , leave it in 4x4 until you come to a complete stop to switch back to 2 wheel drive and vise versa for 4 wheel drive .The transfer case has an easier task matching the gearing and synchronizers to a vehicle that is stopped rather than moving . Less chance of damage this way .
I have repaired thousands of transfer cases . shifter forks , chains and shift hubs take extreme punishment while swapping to 4x4 while moving . If you think about it , you are asking the transfer case to begin turning a crap load of stationary parts .

 

Huh... that's the first i've ever read anyone say it's better the switch between 2WD and 4WD H when stopped rather than while moving. How does the transfer case match the gears when stopped if they're not lined up in the first place?

 

You can engage 4x4 up to 60MPH.

I don't think switching in and out of 4H is going to cause you any damage. Rather help prevent damage by not switching out on dry pavement.

 

Slow speeds in a straight line are the best conditions for the transfer case to make the switch, NOT stopped. The only time you stop is when going between high and low range.

Some people say that switching too often wears down the actuator. So far, in my experience, I have seen the opposite. My patrol vehicle (Chevy Colorado) is notorious for the actuators failing. Mine still works perfectly, and I think it's because I am switching into and out of 4 wheel multiple times every day.

 

^ I agree... and it's best to do it (going into 4HI and back into 2WD) with no load on the driveline... just briefly take your foot off the gas pedal before making the switch.

 

This is from the manual:
_________________________________________________________________



Shifting between H2 and H4
-Shifting from H2 to H4
Reduce the vehicle speed to less than 62 mph (100 km/h) and turn the
front-wheel drive control switch fully clockwise.
-Shifting from H4 to H2
Turn the front-wheel drive control switch fully counterclockwise.
This can be done at any speed. You need not depress the clutch pedal.
(manual transmission)
If the four-wheel drive indicator light or the 4LO indicator light blinks
-Shifting from H2 to H4
• If the four-wheel drive indicator continues to blink, drive straight ahead
while accelerating or decelerating.
• If the four-wheel drive indicator continues to blink and the buzzer
sounds, stop the vehicle or reduce the vehicle speed to less than 62
mph (100 km/h). Operate the switch again.
-Shifting from H4 to H2
If the four-wheel drive indicator continues to blink, drive straight ahead
while accelerating or decelerating, or drive forward or backward in a short
distance.

 

The reason you don't want to be in 4WD on pavement is that these systems are designed to have the front wheels turn slightly faster than the rears. This is done so that turns are easier in that during a turn the front wheels have to travel further over the road than the rears. If all 4 wheels traveled at the same speed during a turn, the front wheels would tend to plow creating a condition with less control.

 

I switch mine between 2 and 4 a lot. I don't think there's much to worry about when it comes to the actuator

 

I put it in 4WD when I need it and 2WD when I don't , if the front is binding you need to widen your turn or stick in 2WD

Switching back in forth is no big deal IMO , but you have to be moving somewhat for it to engage

Taking your foot off the accelerator and going straight while you switch over seems to smooth out the transition

 

Definitely be coasting when you switch.

 

Ok, whew.... I think you can get some idea of what to do by "feel" too. I'd been switching multiple times a day and, through small trial and error, found that taking my foot off the gas pedal is much smoother than under power. I don't get the "clunk", as many of you mentioned.

Just by "feel" I'd been doing the right thing. I wasn't certain though, so that's a relief. The manual doesn't delve into the topic of switching multiple times a day.

If I wear out an actuator over the next 5-7 years by switching a lot, I'll just have to buy another actuator. It's excellent control over the road w/ 4wd.

Thanks for all the responses.

 

Hate to resurrect this old thread, but I have a question stemming from a recent occurrence.

I was out off-road on some trails near Colfax, Norcal when some friends and I decided to call it a day. I was tired, and I forgot that I left the 4wd selector dial in H4. We drove until the end of the trail, where the loose gravel turned back into pavement. We went down said paved road, which had some moderate curves, when we decided to pull into a gas station.

Turning in to the gas station, the front tires chirped, and I realized that I had left the truck in H4 on paved, occasionally twisty road for maybe 10-12 miles.

There have been no odd sounds or vibrations this past week. Truck has 5300 miles.

How much strain/wear could this have realistically added to my drivetrain, and what should I check on the truck to see if everything is fine? I may be more or less paranoid, but I like to be safe rather than sorry. Thanks.

 

It'll be fine. Where you noticed the tires chirping is when it had the most stress. Not enough to do anything. If you did it all the time, then things might start to wear out or break. I wouldn't worry about it.

 

X2

 

LOL no not even close.

Front and rear diff's are geared EXACTLY the same. The reason why the 4WD system binds in a turn is because there is no center diff as we have a PART time 4wd system. When making a turn in ANY 4 wheeled vehicle the front tires follow a different arc than the rear, Just like the inside and outside tires, this causes a difference in rotational speed between the front and rear, causing the binding sensation. (same sensation happens with the rear diff locked in 2wd)

DO NOT drive your truck on high traction surfaces in 4WD if you plan on making anything but slight turns.... its perfectly OK to pop it in 4wd on a straight stretch of dry pavement to work the actuators and spin everything.... but anything over a bend tighter than what you find on a freeway put it in 2wd.

Also they way the 4x4 system is designed on the tacoma, there is no harm switching into and out of 4HI at speed. You can try and switch it to 4 low at speed but the system isnt even going to try untill you are under 3mph and in neutral.

 

Alright, thanks for the info. Now I can sleep at night

 

Both turn the same speed other wise the axle ratios would be different. When you make a turn the outside wheel turns faster than the inside (it has to go further to make the turn) that is how a differential works it allows this to happen. When you have it in 4WD the outside rear tries to turn the inside front at the same speed as the outside rear that is where the binding comes from.