Is it bad to reverse in 4WD??

[nvanadm]

So, i've read all the 4x4 threads and haven't noticed anything about reversing in 4WD...

I drive a '93 Super Exceed with the auto locking hubs and know that driving in 2WD in reverse will unlock the hubs, but when i'm in 4WD reversing out of my driveway (which is on a hill) the "Wheel Lock" light goes off. And then when I move forward the "wheel lock" light comes back on.

Should I be reversing in 4WD?? I read in the 4x4 threads that you should only be in 4WD when the "wheel lock" light is on.

Thanks,
Adam

[konadog]

You can for sure backup in 4x4 mode. I have neither auto locking hubs nor indicator lamps on the dash (never had the wheel-lock lamp and the 4x4 one died a couple of minutes after the first time I used the 4x4). Put some tape over the indicator lamps and pay attention to the position of the transfer case shifter and to the sounds your auto-hubs make locking and unlocking instead. If you locked them and have not moved the TC shifter into 2wd and backed up, the hubs are still locked. Remember what position you leave things in and keep track of the changes

[The Pinkfingers]

If you couldn't reverse in 4wd, there would be alot of stuck vehicles out there.

Like Kona said, the "clunk" is a better indicator than the light. If you are reversing out of your driveway, you have to drive forward in 4x4 until you hear the clunk. If you just start the car, put it in 4x4 and reverse, the light will go off because you never truly engaged the 4x4 by driving forward.

[nvanadm]

If you couldn't reverse in 4wd, there would be alot of stuck vehicles out there.

That's what I thought...And i'm also going forward into my driveway in 4WD so I know 4x4 is engaged, but I just wanted to make sure I didn't ruin anything after seeing those pics.

Thanks for the responses.

[Green1]

you can even lock the hubs using reverse instead of forward, so if you were driving in 2H with hubs unlocked, and then want to back in to a tricky spot, simply come to a stop, put it in reverse, put it to 4Hi, and the hubs will engage as you reverse (I do this frequently in to my parking stall at home, when snowed in it can get quite tricky)

[torchard]

I still don't fully understand how the 4wd system works in these things, in part 'cause this is my first time with auto hubs, but my sense is that when shifting the transfer case to 4wd high or low it fires a solenoid or some such which engages the hub. The hubs will stay engaged when in forward or reverse and disengage only when transfer case is moved back to 2wd mode. Does this sound correct?

--Todd

[loki]

I still don't fully understand how the 4wd system works in these things, in part 'cause this is my first time with auto hubs, but my sense is that when shifting the transfer case to 4wd high or low it fires a solenoid or some such which engages the hub. The hubs will stay engaged when in forward or reverse and disengage only when transfer case is moved back to 2wd mode. Does this sound correct?

--Todd

partially, but you need to ass "and reverse 5 or 10 feet" right after "back to 2wd mode"

[nvanadm]

you can even lock the hubs using reverse instead of forward

Yeah, I noticed that today. Thanks for making it known to me that it's normal to do!

Thanks,
Adam

[Erebus]

but my sense is that when shifting the transfer case to 4wd high or low it fires a solenoid or some such which engages the hub.

Notice that our hubs say "auto unlocking" not "auto locking" Subtle difference.

Think more like a bolt being tightened up. The wheel side of the hub is turning all the time. When you put it into 4Hi for the first time, the transfer case starts to turn the front drive shaft, diff, and half-shafts into the hubs. That makes the inner side of the hubs turn and (let's pretend) expand to jam its teeth against the outer teeth that are part of the wheel side that are already turning.

That's why you have to be driving in a straight line, otherwise there is a differential between the hub speed and the half-shaft speed. And if you switch to 4H with hubs unlocked and you are stuck, then it will engage without the outer side turning. Can you say "loud clunk".

Your hubs are now locked, and stay that way until...

The hubs will stay engaged when in forward or reverse and disengage only when transfer case is moved back to 2wd mode. Does this sound correct?

Yup. When you back up in 2H, the transfer case stops turning the driveshaft, diff and half-shafts. But they are still turning because they are connected to the hubs. But by going in reverse, the inside of the hub "unscrews" from outside of the hub. You are now unlocked, and the half-shaft, diff, and driveshaft stop turning.

This all might not be technically correct, but that's how I think of it.

The "wheel lock" light detects turning of the driveshaft, rather than the exact setting of the hub. So the light isn't always right. The other day, I backed up a couple of feet in 2H. The light stayed on, so I thought I still had locked hubs. When I went to put it into 4H, there was grinding noise. Yanked lever back into 4H, but there was a loud whining. So I stopped, put it into 4H, went forward and the hubs locked again. Clearly, they weren't locked, and not locked either, but 1/2 way in between. Oops.

I also notice that when I park and shut off the engine with the hubs locked, when I restart the wheel lock light will be off until I move a little.