Sharp turn in 4hi in drive pavement

I try to engage 4h and drive in straight line for a mile or two every week. Today I engaged the 4 low in neutral and went back in 4hi. And forgot didn’t put it in 2wd. I turned the wheel completely to enter my driveway. I realized car was having a hard time driving up and realized The car is in 4h. I straightened the wheel backed out and put the car in 2wd. I went up and down street and engaged 4wd again it was fine. I did not hear any noise or anything. The only giveaway was that the car was having very hard time driving up highway when the wheel was turned. I realized quickly and didn’t try to accelerate more to go up.

Could one sharp turn in dry pavement In 4h damage the truck?

 

From my understanding, it's fine until it isn't. So if you didn't feel something break, it should be fine.

If there was a loud pop or boom, and suddenly it was easy to turn, that would be a problem.

 

You should be fine. I wouldn't be driving miles at a time in 4wd on dry pavement thought. The 4wd system needs to have slippage to operate properly. I engage mine once a once a month but only leave it engaged for a very short time.

 

You are fine. I've been driving these trucks for 25 years. I forget to take it out of 4 high quite often. I'm usually reminded by situations just like yours.

I've lost count how many times I've done this over the years.

There has never been a failure.

 

You won’t hurt anything driving in a fairly straight line with smooth curves like most highways. There’s not enough difference in wheel speed to need slippage under those conditions so nothing can be damaged.

 

No true. The problem is the wheels all turning at the same speed. Traditional 4wd like the Tacoma need to have slippage to prevent the system from binding.

You should 1000% not jump on the highway and drive for miles on dry pavement with the 4wd engaged.

 

I disagree. Normal curves on the xway are not going to affect the 4 wheel drive system when on dry roads.

Sharp, low speed turns on dry roads are the only thing that will result with what the OP described.

 

I disagree with this. The front and rear travel different radii when taking sharp turns but at higher speed with an essentially straight road there really isn’t a significant difference front vs rear wheels and the open differentials can manage side to side differences. I drive my truck about 5 miles a month on the highway to “workout” the actuators and solenoids. There is no binding or clunking (signifying drivetrain preload) when disengaging 4wd and while driving there is not any additional resistance to steering effort.

Sharp turns I would obviously avoid making a habit of.

 

You are partially correct. Both axles have to spin the same speed (locked at the transfer case) but each wheel on the axle can still have different speeds due to the open differential. On normal highways there is no danger when driving in 4hi for a bit.

 

Binding can happen even with very small turns. Any sort of difference is tire speed(IE a small turn) can contribute to bind. Sorry but it's not a good idea to do this. Its 4wd basics.

 

I have done this many times over the years forgetting to take it out of 4wd till I turn then it just scares the shit out of me till you realize it is in 4wd. No damage was ever done but I do give myself shit for not paying attention. just saying.

 

You all seem to think these things are a delicate flowers, No it's not a good thing to turn sharp turns in 4WD on the pavement but it will let you know right away. The tires will slip before there is any damage, think about off road climbing rocks etc. and 4WD why is that different? The out side rear is trying to turn the inside front at it's speed when you turn.

 

Do you take your truck out and drive on a dry highway in 4wd for miles at a time?

 

Same here. I've gotten back to pavement, made a turn or two, pulled over, gon back to 2wd and not broken anything in 200k miles.

 

Should be fine. Just don't make a habit of it. On one hand, 4x4 needs slip to work properly. On the other hand, people rock crawl with these things. It's all about what risk you're willing to take.

 

The strain on the system when actually driving off-road is 100X more than whatever you did in your driveway. Keep in mind hardcore fellas blow up their front CV joints all the time, which means the rest of us are coming very close to blowing up our CVs some of the time, without knowing it.

I’ve never once read of a guy who blew up his CV joint in his driveway. The CV joints are purposely the weak point so you don’t damage your diff. If your CVs didn’t blow, the rest is all good.

 

The manual says to exercise 4x4 once per month for 10 miles. I put it in 4HI on a straight road after a first rain when the roads are slick. Besides exercising, be sure to change your fluids on schedule. Yes, I too have forgotten to take it out of 4HI and had the steering bind a handful of times. I change my Combo meter to the blank screen as a reminder I am in 4HI. You should be fine.

 

There must be dead and disabled tacomas all over Moab if this is really such a serious problem.

 

If it's ok why do most write-ups on the subject (and the owners manual) advise against it?

 

Just because you don't feel anything going wrong doesn't mean you aren't putting extra stress on driveline components.

Driving 5 miles doesn't exercise your "actuators and solenoids" any more than it would driving ten feet. engaging and disengaging 4wd is what exercises them, not driving miles.