4wd - 2wd limitations

lumberjack · Dec 3, 2004

Hi,

I am a forestry student in Scotland. I am busy doing a project on 2 differant tractors of my choice. One must be a 4wd and the other 2wd. One of the question are- State the typical uses and limitations of each one. Any help will be great.

meledward23 · Dec 3, 2004

I didnt know my 4wheel drive had limitations /forums/images/graemlins/cool.gif ...... (it might beg to differ).

My experience in Four wheel drive vs two wheel drive has mainly been in using the FEL with not enough counter weight. Carrying a heavy load on the FEL which makes the rear end light and not carrying the weight of the tractor. This makes 4wd an important factor in soft ground, and backing out of a location.

Limitations of 4wd is that it is a pain to steer so should only be used where necessary.

I am sure the is much more to be expounded upon......

jinman · Dec 3, 2004

( State the typical uses and limitations of each one. )

Lumberjack, I can think of many limitations of both of these tractors, but I'm going to give you the one that I think is the most important to me.

If you install a loader on a 2wd tractor, the tractor must have lots of weight on the rear tires or it will lose traction when the loader bucket is full. I had a 2wd tractor that was so poorly designed I could not climb a small hill on a gravel road with the bucket over half-full of dirt. With a 4wd tractor, this is no problem because the front wheels provide the traction when the loader is full. /forums/images/graemlins/cool.gif

Logan · Dec 3, 2004

Lumberjack,
4X4 = twice the grip getting stopped on a steep slope. Very important if its a consideration.

ZJ_HR · Dec 3, 2004

We had two 4wd tractors during 27 years.
One of them (bought 1981, new) was transformed to 4WD in 1996, so I have experience with same tractor in both versions.
Our tractors are used only on fields and medows. We don't have FEL.

2wd tractor is good for 3pt mounted implements, especially ones that transfer weight to rear wheels.
Example is drill, planter etc.
Advantage is smaller turning radius and lighter machine for equal engine. Good enough for pulling low coupled single axle trailors.

4wd tractor is better for any draft (pulling) work. Implements that transfer weight to rear wheels (3pt bottom plow)decrease front wheels grip, what is easy to correct with front weights added.
Advantage and main difference compared to 2wd tractor are:
- better grip with lighter machine
- tractor will allways go to reverse, like to forward
- all wheels braking - safer on slopes
- easier steering ( in muddy conditions )
- better weight distribution (usually 40:60%), harder to jump up front end - more safety
- better look /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
- possibility to carry front mounted implements (mean serious attachments, not a snow plow)
- better resale value, easier to sell

Disadvantages:
- bigger turning radius
- heavier compared to equal 2wd tractor, harder for engine
- bigger fuel consumption for road transport, more resistance in transmission.
- 20-30% higher purchasing price

After 6 years of experience with 4wd tractors, we bought another 4wd tractor (2002), and will NEVER again buy 2wd one.

Hope this helps

sneaky_pete · Dec 3, 2004

( Hi,

I am a forestry student in Scotland.)

He sleeps all night, and he works all day... /forums/images/graemlins/smirk.gif

O-levels in tractorology??? Oh well, my wife is a Scot.

( I am busy doing a project on 2 differant tractors of my choice. One must be a 4wd and the other 2wd. One of the question are- State the typical uses and limitations of each one. Any help will be great.)

The 4wd will get better traction and hence better ground engagement on implements that need that, for a little more initial cost and maintenance.

Pete

Casimir · Dec 3, 2004

4WD will get you a lot deeper into the mud hole before you get stuck! /forums/images/graemlins/shocked.gif

Seriously, in muddy, icy or sandy conditions, the 4WD will get around a lot better without getting stuck, but it sometimes can get you deeper into trouble before you realize it.

GaryK · Dec 3, 2004

I have a smaller compact and except for mowing with a MMM, all FEL and other jobs are done in 4wd. 4wd WILL tear up your lawn when you turn. Mine turns just as good in 4wd as 2wd as long as I am not on a hard surface.

slowzuki · Dec 3, 2004

I assume you are looking at forestry applications. In eastern canada much forestry work is done with farm tractors. I hear this is similar to scandinavian countries.

To take a tractor into the woods where there is wet ground, hills, snow etc to do winching and skidding work, a 4wd tractor is usable about 10 months a year here. Only spring is it too wet.

A 2wd is usuable about 6 months a year being summer and fall after the ground has frozen. This can be extended to the same 10 months a year by using chains on the tires.

The 4wd will be much more productive than the 2wd with chains and will be gentler on the soil.

For doing forwarder type work a 4wd is almost always needed as you will need to get closer to the trees. This forces you into wetter and hillier areas than the winch. It also mean your trees can stay cleaner too.

For loader work the 2wd is near useless in the woods as the winch doesn't have enough weight to work as a counter balance. In a yard area it can be useful to rank up piles of wood and pushing slash out of the way.

The 4wd can do all this plus use the loader to spread gravel etc for temporay roads. A bunch of 2wd nuts will cry oh ours does this just as well but they must live in dry flat areas. In my experience the 2wd is a waste of time doing loader work on muddy hills and rough areas.

Hope this helps!

frank_f15 · Dec 3, 2004

i can think of no time i woud prefer 2wd over4wd., but on those rare occasions just slip into 2 wd., the only disadvantage is a higher cost when purchased. but i personally would not but a 2wd again.

KiotiJohn · Dec 3, 2004

I personally wouldn't have a non-switchable tractor again as I go between the two as needed. The only real disadvantage of 4WD to me is that the gearing is such that, used on hard surfaces, it's hard on the gearing and tires. 2WD is recommended for hard surfaces.
Major disadvantages of 2WD are, as stated, less traction with a loader, wheels may sink into soft soils and can't pull, When pulling trees and such, rear tires may only spin with extra weight where 4WD will pull more. John

Soundguy · Dec 4, 2004

Here's one way to look at it. 4wd gives a smaller tractor a similar advantage as a larger tractor using only 2wd. For instance. Many early and mid to late model af tractors ( 80+ hp ) were 2wd, and very large and heavy. Some used dual rear tires on each side. Tractors do much of their work based on traction. Power has to get to the ground. If you one have 2wd, you need more weight to keep that power moving and not spinning. Agg tractors get the weight advantage as they weight in the 3 ton and up class. Smaller cut's and subcut's are way down on the weight level..less than 2 tons in most cases. Without this weight.. 2wd doesn't cut it was well for some heavy tasks. Locking diferential shelp.. but in many cases like loader work, or soft ground tillage.. 4wd is nice.

Soundguy

eee · Dec 4, 2004

I depend on 4 wheel drive for being able to go off road as well as pulling power. My tractor is virtually useless for my needs in 2 wheel drive. A tractor twice my size that is 2 wheel drive could outpull me in 4 wheel drive,but I can go places in 4 wheel drive that the 2 wheel drive no matter what size could not go.

Egon · Dec 4, 2004

I can go places in 4 wheel drive that the 2 wheel drive no matter what size could not go.

Are you sure of this?

Egon

familyman · Dec 4, 2004

For me the big advantage of 4wd (besides getting unstuck) is maneuverability in soft conditions. I was digging a shallow runnoff ditch the other day, following a spray painted, curving line. The soft ground had a slight pitch, which made the tractor creep and slide off the line as I tried to back the backhoe into position. Shifting into 4wd gave me much improved control, and I got back onto the line. I've also had some touch and go situations while digging deep trenches and relying on planks to get me across where I had dug. Having extra tires pulling when you are at risk of slipping off a plank has saved my bacon (and my tractor) more than once. /forums/images/graemlins/tongue.gif

eee · Dec 4, 2004

( Are you sure of this? )
 Yes I am sure....
Right behind my house,you might get a 2 wheel drive down in the hollows,but you would not get it back out.

Todd_C · Dec 5, 2004

I have limited experience with tractors, but hear's my 2 cents. The area where I live is right in the middle of the Jefferson National Forest. The elevation varies greatly from a 800 feet above sea level to about 4,000 feet above sea level. We get a fair amount of rain and snow (though most snow storms are under 12"). The county where I live is approixmately 85% national forest so most people have gravel driveways and live a long way off state maintained roads. While driving this weekend across the county almost every house had a tractor. The majority of the tractors were 4wd compacts. I did see a few older dual wheeled John Deere 2wd tractors.

I live in a home owner's association at the end of our gravel drive that is almost a mile from a state maintained road. The home owner's association has a Ford 8n that has been used to maintain the road and scrape snow for several years. Two hurricanes went through our area and washed out most of the roads this year. The Ford 8N just did not have enough traction in the mud to rebuild the roads. I used my little TC 30 along side my neighbor on the 8n. I could not believe the difference between my 4wd and the 2wd. I went in places the 2wd couldn't even get to and drug gravel back onto our road. I would never purchase a similar sized 2wd compact when 4wd are available.

eee · Dec 5, 2004

The home owner's association has a Ford 8n that has been used to maintain the road and scrape snow for several years. 

I can vouch for the 8N no traction,we had a big snow here a few years ago and I could hardly get an 8 N that belonged to my neighbor out the road I live on which was virtually a flat stretch of road much less get it in my driveway to clear the snow out. No comparison whatsoever in traction.Of course this all happened befroe I purchased my JD 4400 4x4.

mark777 · Dec 5, 2004

IF....there are any limitations on a 4 wheel drive tractor I can only think of a few.
ONE- 4x4 requires slightly more maintenance;
TWO - tire sizes are critical in relation to gear ratios from front to rear rolling circumferences;
THREE - as many have stated, your original investment is higher when the tractor is equipped with 4x4, but that is usually recovered when selling or trading in as the residual value is higher than a 2x4.

2 wheel drive tractors are fine for applications on firm even ground and are certainly better than anything else except tractors equipped with 4 wheel drive.

There is an old saying here in America about 4x4's: "It's better to have it and not need it then need it and not have it".

Good luck on your project. Regards, Mark

Soundguy · Dec 5, 2004

Another good old saying i remember.. and have experienced...

4 wheel drive just gets you stuck farther from home.

When I had my Nh 1920 4x4... I ran it out acorss a 'dry' pond... that pond that had been dry for 2 years had about 1" of dry crust, then about 2' of soupy muck... tractor sank up to the axles and high center before i could even hit the clutch.

It took digging the wheels out with a shovel, and using my trailer ramps, and the neighbors truck, and two snatch ropes tied together to get the tractor out. We had to use 2 ropes, as the truck couldn't get traction anywhere near the tractor.. hence the saying.. 4x4 gets you stuck farther out.. etc.

I think a very light tractor 4x4 or 2x4, perhaps with wide turf tires might have made it across.. or a big honkin monster ag tractor with dual rears, and 6' tall tires would have done ok as well, as the muck firmed up to solid clay at about 2' to 2.5' A large rim/tired tractor could have sunk that 2', hit good ground and then kept going.. Unfortunately I was in the wrong machine!.. not light enough.. and tires / rims not big enough!

Soundguy