all i can say is try calling toyota and telling them that you have a problem w/ your truck and that you have been driving around on dry pavement in 4 wheel drive and see how far you get. you will get as far as hearing them laugh and hearing a click on the other end of the line. read the card above again as it is in my truck too. it does say 4hi is for OFFROAD use . discussion over.

 

You have a part time 4Wd and its not to be driven in 4Wd on any road surfaces unless its slippery. If tis slippery, 4WD is fine. But keep in mind braking isnt any better, UNLESS you use engine braking, ie gearing down. Makes a huge difference. But still be careful.

 

My hubs have been locked since the morning of the 20th when it started snowing. I have been going as fast as 65mph on the snow. Too fast, maybe, but I vary my speed upon a lot of different factors. I am very comfortable driving on snow & snow packed roads, one benefit of twelve winters with rear wheel drive in Alaska. If I driving fast it is because I feel that the traction I derive from 4Hi will help. I do not suggest a lot of brake pedal for stopping, use the engine to brake. There are days that I will let every body go faster than me, when I feel that the roads are absolutely nasty.

I try to always make sure that I am not in 4Hi on dry pavement, driving gets to interesting then.

You should only drive how you are comfortable driving, I can guarantee that some of the offroad driving that I have seen in the pics here wigs me out. Hence I need to go practice.

Off the soapbox now

 

Oh, but there is.

 

It is NOT a good idea to drive in 4hi on pavement, turning, straight...EITHER is bad. Even when straight, tire diameters are different due to wear, and it puts a major strain on the tcase.
I once got my dads gmc stuck in 4hi out in the sand dunes and tried to get it 15mi back to our motel.... TOTALLY overheated the tcase, it was smoking. Had to drop the front driveshaft to free it up. Ate up the unit, needed to replace.
The slippery surface is needed for it to have some give.

I don't give a shh if the manual doesn't explicitly warn against it, use your f-in brain if you have one and learn about how the system works, then you'll understand.

 

few more examples...

http://www.ttora.com/forum/showthread.php?t=53327

http://www.ttora.com/forum/showthread.php?t=49980

 

You know... The southern half of texas is frozen over right now. This discussion actually came in handy lol. I dunno how yall folks up north deal with this. San Antonio's been completely shut down for 2 days now.

One thing I learned trying to drive on ice today was that startin in 2nd really helps. Even in 4hi, I kept on spinning my tires reguardless of what I'd do. Woulda gone out and bought some chains for my tires, but I honestly don't think anyone sells or makes tire chains here in southern texas lmao... Oh god, I caint wait till it hits 110* soon...

 

Oh my gosh!

If you hit a dry patch your diffs are gonna explode!!!!!!!!!!!!

lol

I wish it would ice over down here just once so I could go sit on a corner and watch in amazement...

I damned sure wouldn't want to drive in it though, people down here have never seen ice.

 

Yep. Just hit it right on the head. Yall over there in flordia are basically as "cold-less" as us in texas are. It was insanity.

 

Yes, It is safe to drive in 2WD with the hubs locked. Gas milage is reduced but no damage will occur. When you find you need extra traction, slip into 4Hi and continue on. Once you are on clear pavement again, slip out of 4Hi and back in 2WD.

 

I don't know why you would drive in 2H with the hubs locked? You are turning everything in the driveline anyways just not putting power through it. The only thing that changes is that you save the torque buildup in the T-case if you are running on dry pavement for a very long time. If you are driving on dry that long I would unlock the hubs.

Just my 2 cents.

 

no when your driving with the hubs unlocked the axles do not spin. when you LOCK them they spin with the rest of the driveline.

 

I'll sometimes throw mine in and leave em that way for weeks.. even if I am mostly in 2wd. If its winter I just lock em.. then you have 4wd on the fly when needed....

Not sure who you are replying too, but I think you missread... I dont see anybody saying that they spin with the hubs unlocked...

 

Hey, doesn't limited slip diffs allow for dry pavement 4wd? Seems like somewhere on this site there is a write up on the the different types of 4wd's...there limitations and abilities. Does anyone remember or know where that is? I'll keep searching.

 

Lockers or limited slips front and rear would bind like hell on dry pavement, but open diffs won't...

And guess which one a stock yota has front and rear?

 

A limited slip works fine on dry pavement as does an open diff and even an automatic locker (they will click and pop every once in a while). But the issue is not only the differentials in the axles (front and rear) but also the center differential (or lack thereof). If you have a part time 4WD system (i.e. a gear- or chain-driven) transfer case, you have no center differential. This means in 4WD, the front and rear driveshafts turn exactly the same speed and therefore allow no "differential" in the speed of the front and rear tires. Why does this matter? Find an empty parking lot with a puddle. Drive through the puddle then make a hard u-turn. Hop out and look the the tire tread marks on the pavement. See how the front tires follow a wider arc than the rear tires? Wider arc = more distance travelled = more wheel rotations = drivetrain binding.

 

i do it because i dont want to get out of the truck twice a day to lock and unlock the hubs

 

my hubs are locked as of now until the weather clears up, and when the ground becomes snow covered later its going into 4hi on the highway, but i dont plan on doing over 40 then.

 

edit. Letting it go...

 

My truck, i know its newer, but the manual states that i can utilize four high on pavement driving as long as i am below fifty miles per hour to engage it, but i don't know about max speed. Tangent