Having 4WD on road? (1 Viewer)

[Lantec]

I was wondering if it will damage the gear box or transfer cases for using 4WD on the road?

Or can I leave the front axles locked and not push the 4WD button until I need it.

I know on my mom's old QX4, there was three modes, 2WD, Auto and Locked. In Locked, you can only do 80km/h max and it wasn't recommended to be used used all the time or it'll damage the transmission.

Do the landcruisers' 4WD option also referring to the "locked" option?

 

[cruiser88]

having it in 4 wheel on the hard top is not good at all

 

[Island Moose]

You can lock the front wheels, but engaging 4H or (God forbid) 4L on dry pavement is really bad news. These trucks don't have the fancy "instant on-off" feature that modern SUV's have. If you're driving along and the road gets bad, you will need to slow to a stop and engage 4x4.

 

[Lantec]

You can lock the front wheels, but engaging 4H or (God forbid) 4L on dry pavement is really bad news. These trucks don't have the fancy "instant on-off" feature that modern SUV's have. If you're driving along and the road gets bad, you will need to slow to a stop and engage 4x4.

How about disengaging? Do I need to slow to a stop as well? and is there a speed limit when I'm in 4WD? I guess I won't be/shouldn't be going over 80km/h anyway

 

[Syndrome]

Why would you want to stay in 4WD when you're not offroad? It only takes seconds to shift between 2- and 4WD, and like the previous replies say, you'll do damage using 4WD on hard surfaces like a highway.

I guess it could become irksome if you live someplace where the roads often alternate between gravel and bitumen over short distances, but even then you should be fine in 2WD unless there's a swamp or quarry in the middle of the street!

 

[roscoFJ73]

How about disengaging? Do I need to slow to a stop as well? and is there a speed limit when I'm in 4WD? I guess I won't be/shouldn't be going over 80km/h anyway

Someone on the 60 forum dragged out an old brochure that says the push button 4wd can be engaged at up to 75kmh from memory.

I never change unless Im under 30kmh. The front and rear wheels MUST be turning at the same speed with the steering more or less straight ahead to engage 4wd.
If you drive onto a soft surface and the rear wheels lose traction ,you must resist the urge to push the button.
You have to stop the rear wheel spin and then engage 4wd.

Its ok to leave the front hubs locked. Most part time 4wd were permanantly locked until the early 1980s until FWH became an aftermarket accessory and later became standard a standard feature

 

[UpsideDown]

It's perfectly okay to engage 4wd High at highway speeds as long as the hubs are locked and you are going pretty much straight ahead.

To engage 4wd Low you should be at a stop, or very close to stopped.

Using 4wd hi on the pavement is not that likely to cause damage, though it is possible, but you will experience gear bind (feels like heavy steering) and you will wear your tires out much faster (something has to slip...). The larger the tires, the more likely you are to hurt things with 4wd engaged.

You can, however, drive around as much as you like with your hubs locked if you're not engaged in 4wd. If everything is in good shape, you will only notice a bit more vibration and fuel consumption.

I also prefer a manual shift to a push-button for 4wd because you can feel the 'case engage and disengage... and know the dog teeth are meshing properly.

 

[crushers]

i tis fine to drive with the hubs locked as stated above. this is very nice in the winter road conditions where ice or snow can be present with dry sections for long distances. see ice, engage, dry pavement then disengage... do not run with hubs locked and in 4H on hard packed gravel, dirt or pavement as very expensive repair bills can result...
the push button (as long as the front hubs are locked) can be engaged or disengaged at ANY speed as long as the truck is traveling straight ahead. shoudl you encounter gear bind when disengageing then gently let off on the throttle or give it a shot and the gear bind will be unloaded and the transfer will disengage.
i have been practicing this for many, many years. if you have a locker in the rear or a heavy foot then i do this on loose gravel as well especially if a wash board or sharp bends can be encountered...

cheers

 

[4x4abc]

Lantec,

yes, you will damage your transfer case (or some other parts within the driveline) when you use 4WD on pavement.
See: http://www.4x4abc.com/4WD101/driveline-bind.html

You can leave the front hubs locked on pavement though (locked axles are something completely different) - however, depending on the condition of your truck, you may get some nasty vibrations while driving at higher speeds.

more on hubs - to lock or not to lock: http://www.4x4abc.com/4WD101/hubs.html

Cheers!

 

[Lantec]

Thanks guy, just wanted to clear up most of my questions before i start driving it more often. I dun want to break anything :S

 

[Jim_Hbar]

Lantec:

I've driven 4WD's for over 30 years - We always lock the front end in the fall (winterizing) and unlock it in the spring..... If you do that, then you can have 4wd when you need it, and not have to worry about a hub that won't engage at the wrong time.. When you head off the pavement in the summer, I always lock my hubs right away - then you don't have to turn them in when you are stuck in the mud, or when you come across a bunch of wash-board (4wd really smooths the washboard out, when you're going up hill BTW)...

Listen to the guys above WRT when you should and shouldn't engage 4wd!! Personally, I've found that the vehicle tends to wander a bit more when the hubs are engaged. When most vehicles had hubs, they recommended running them engaged for something like 10% of the time.

 

[Malahki]

So it is OK to engadge 4HI button at any speed when going straight but can I engadge 4HI button when the shifter is in 4LOW?

 

[Greg_B]

So it is OK to engadge 4HI button at any speed when going straight but can I engadge 4HI button when the shifter is in 4LOW?

When you go into 4Lo there is a sensor that activates and puts your t-case into 4wd. This bypass's the 4hi button on the dash.

You get get around this by disconnecting the plug at the t-case. There are two, and I forget which one is it you need to unplug.

You then are able to have 2L only, which is a nice option in some situations.

hth's

gb

 

[isabri]

When on an uphill tarmac road, I sometimes engage 4H (manual)to gain extra boost of an otherwise slow and unpowerful drive. Since my LC is with manual hub lock, this manuevre would only provide lower gear ratio and only the rear wheel will be engaged. Techincally, I'd be on 2 wheel drive but with a lower gearing ratio. Does this make sense?

 

[crushers]

actually, engaging 4H with the hubs unlocked will be of no benefit at all. the gearing remains the same but to go to 4L (engaged at a stop) with the hubs unlocked will give you anywhere from 1.96 - (what ever your low range gearing is) in crease in torque. it will be slow but much more power...
cheers

 

[Malahki]

If my shifter is in 4low and I push the 4Hi button will the t-case go into 4Hi or do I need to put the shifter back into 2Hi before engadging the 4Hi button??

 

[crushers]

4 low automaticly engages the front diff.
as soon as you disengage the 4L then the front end disengages so you need to push the button for 4H,

 

[Malahki]

Is this question just so stupid that your missing what I'm trying to ask. I want to know if I can go directly from 4low into 4Hi without moving the transfercase gear shift into 2Hi but by only pushing the 4Hi button.

I was told I could by somebody but have never tried (just in case). I think it would be handy on the trail when you get to a short spot where you no longer need to be in 4low but don't want to always be stopping and shifting the transfercase gear shift into 2Hi and then engadging the 4Hi button.

Maybe this question is stupid but I still need to ask....

 

[Jim_Hbar]

BJ71

The only way to get to 4Hi from 4Lo is to move the lever...And you should be stopped.. Having the 4Hi button pushed while you are in 4Lo doesn't hurt anything. And you aren't going to hurt anything by having the 4Hi button pushed when you shift the lever either up or down.

The transfer case has two functions - Hi - N - Lo (the lever) and front driveshaft engaged/disengaged...(the button pushed, or the switch in the transfer case made) - Pushing the 4hi button engages the front drive - switching the lever to low changes the internal gear ratio, and makes a switch which engages the front drive.

Most manufacturers will not let you get to 2wd - Lo, so like Greg posted above, Toyota automatically turns the front drive on when lo range is selected. Lots of old transfer cases were mechanically detented so one couldn't get to 2Lo, but it is virtually always there.

Does that answer your question?

BTW, I always turn on my hubs when I hit gravel, then pop into 4HI when I encounter wash-board, or rocks going uphill. I do it when I'm moving, just as long as my wheels aren't spinning - both into and out of 4HI... If it gets too steep for hi range, I stop and shift into 4Lo - but don't touch the buttons...

 

[Malahki]

So it was a stupid question...............ha ha

That is what I thought but just wanted to be sure, as I said a friend of mine was trying to convince me otherwise. It is good to know however that it doesn't hurt anything to leave the button pushed in when in 4Low.

Thanks