4 wheel drive all the time? or just when needed

[SmallChange]

[...] the front drive system breaks and locks up when driving on pavement, causing a very sudden stop [...]

Really? Yikes. Can you point me to one of these? Do you remember a detail I could search with?

 

[Diggin It]

Really? Yikes. Can you point me to one of these? Do you remember a detail I could search with?

I remember others, but this was all I could find:

L3940D FRONT WHEELS LOCKED !! RIDDLE ME THIS??

Tractor: L3940D hydrostatic 4 wheel drive. Problem: Reversing tractor in 2 wheel drive. Will reverse in 4 wheel drive. HERE IS WHAT HAPPENED IN SEQUENCE. 1. Running into town about 1.5 miles to pickup an old motor. I was traveling at full speed along the shoulder. WITHOUT ME REALIZING THAT...

www.tractorbynet.com

 

[SmallChange]

Well, that certainly did it. But 1.5 miles at full speed, well, that's a lot of stress to build up. Still, I wouldn't have expected that to happen, so it's a good data point to notice.

 

[IndyJay]

Really? Yikes. Can you point me to one of these? Do you remember a detail I could search with?

I ran my old Massey 1250 tractor in 4WD full time except on pavement. My land is gently rolling to some pretty good hills. Front loader was always installed and 90% time had the SQ60 Bush Hog attached, otherwise a 60" box blade or auger. About 15 years of running fulltime 4WD the front wheels locked up solid, even when I took it out of 4WD. I had to ride back from the field riding on the bucket, steering with the brakes. That time I was able to drive it the rest of the way to the barn by disconnecting the drive shaft. That was an expensive repair, they had to split the tractor. A few years later the front axle locked up. That was almost as expensive as the trans-axle considering parts were getting scarce. After that I was a little more selective of engaging 4WD. With my new tractor it is on when mowing hilly terrain, off before I come through the gate to the barn.

 

[ptsg]

I stripped the splines of the U joint on a Kubota B7000 a looong time ago when I didn't knew any better. It happened a couple years after I built and added the loader to it, that really put the stress on the front axle.

Luckily it stripped the splines on the U joint and not the splines on the pinion shaft of the front axle, so that mishap only cost me around €70.

And this is what happens on tractors without loaders and people do not care and run with 4WD engaged all the time, regardless of the type of surface. Pic from an ad:

These are obviously extreme cases that won't happen right away, however, if done enough times it will damage something eventually.

Spending 2 seconds disengaging the 4WD when not necessary can save a lot of money in the long term.

 

[ning]

I can tell when the front wheels are engaged in both my tractor and my truck (97 F350); it definitely can be felt in the steering and how it drives, and how much the ground gets chewed up. I strenuously avoid 4wd on pavement unless it's literally only a few feet.

My land is half flat and half hill steep enough to go Mr Toad's Wild Ride; I always check that I'm in 4wd before going downhill - often finding myself already there, but not always.

 

[CH4Ohio]

Would anyone run their truck in 4 wheel drive all the time? Wheel hops, tearing up ground, stress and strain on the drivetrain. Use it when you need it. Don't need to be conservative about it, but using it on dry flat ground or pavement when not needed just doesn't make sense.

 

[ptsg]

Would anyone run their truck in 4 wheel drive all the time? Wheel hops, tearing up ground, stress and strain on the drivetrain. Use it when you need it. Don't need to be conservative about it, but using it on dry flat ground or pavement when not needed just doesn't make sense.

I've done it several times and some times up to 60 mph too. Not really all the time but when the conditions required it.

However, the vehicles I've done this, were a Mitsubishi Pajero/Montero and my current truck, a Mitsubishi L200. Both of which had the Super Select 2 transfer case. This transfer case has 4 positions: 2WD, 4WD with open center diff, 4WD with locked center diff and 4WD with locked center diff and low range. So it could basically run as an AWD vehicle.

 

[Jstpssng]

I would modify these a little.

1. When you need MFWD because of low traction conditions in a properly ballasted tractor, use it. When you need MFWD because of too much front weight and not enough rear, don't engage MFWD, you need to add rear ballast.

3. When either will work fine, disengage MFWD.

4. When you have started down a hill and the rear loses traction, without question you should time-travel back to before you started down the hill and add sufficient rear ballast or back down the hill. If you still slip despite appropriate ballast, you should time-travel back and get R1 tires. If you already have R1s, you should re-evaluate what you are trying to do.

I can't stress the need for appropriate ballast enough. Using MFWD as a band-aid to try to get away without using enough ballast is what leads to dangerous slippage with lack of control and machine damage.

As has been pointed out several times previously, it also makes the difference between having two wheels stopping and four. No amount of ballast is going to change that.

 

[Jstpssng]

Agreed. But, ANYTHING when going downhill out of control can lead to less than desirable results.

We're making this too complicated. It's simple:

1: When you need 4WD, in low traction conditions especially with too much front weight and not enough rear, use it.

2: When you need 2WD, in high traction conditions especially with lots of tight radius steering on grippy or sensitive surfaces, use that.

3: When either will work fine, congratulations, you're golden.

4: When you have started down a hill in 2WD and then the rear loses traction, without question you should time-travel back to before you started down the hill, and engage 4WD. You're welcome.

Then there was the time that I headed down an icy hill with front end engaged and chains on the rear. I thought that I was moving right along and picking up more speed than I should have been... then noticed the wheels weren't moving.

That was the point I wanted to time-travel back to before I started down the hill, and gone home instead.