Rears *Too* Heavy?

[Kodiak]

Hi Jim:

I have a couple of suggestions. First try reducing your air pressure in your tires. I have a TC29, same size and weight as yours. Currently I am running 12 in the rears and 15 in the front. I run the fronts a little stiffer as I do a lot of loader work. By lowering them you are providing a larger, more flexible footprint, that produces less pounds per square inch over the same area. Second try to make your turns as wide you can. When your running at PTO RPM if you make a tight turn sometimes the inside rear tire gets a little light and has a tendency to just barely spin.

I don't have supersteer on my tractor so I am not familiar with all its functions. Can you you turn the steerable axle off, and just run the conventional steering? If so you might want to run like that while the grass is under this drought stress.

Also you mentioned this as happening on hills. It could be a matter of your soil is not as compacted on the hills. Some soils, especially those that contain a lot of sand never adhere to hills as well as it does on a flat area. And some soils don't develop a good turf root base on hills. Just somethings that might help you.

 

[webbmeister]

Thanks, Russ:

I'll check the pressure and drop it a little this weekend. As for the turns, it is not there (in particular) that the problem is. I have long straight-aways over which the brown tire marks stretch.

As for the SuperSteer, the best I can tell is that when the sensitrack in on, you're in 2wd except when the tractor senses that you need fwd. It then shifts back to 2wd when the slippage stops. The only other choice that I can see is locking it in fwd. So, there is no (that I can see) locking it into 2wd.

That is a good thought on the hills - although I am now hoping that by lowering the tire pressure I can lessen some of that damage.

Thanks for the great reply!

Jim

 

[webbmeister]

I learned a few things about the brown tire marks this weekend.

First, on level ground, as in the area in my neighbor's yard that I marked up with brown streaks several weeks ago, the brown streaks do not occur if the grass is not overly dry when the tires go over it. I mowed his side yard for him yesterday, and when I came back to work on my property today, there were no tracks - brown or otherwise. Lesson 1: Don't use Thor to mow when the grass is dry and stressed.

Second, when going down a steep hill, if the tractor is heavy and wants to go down the hill faster than the hydro wants to let the wheels spin, the tractor will slide down the hill with the tires scuffing the grass out at ground level. This essentially makes brown skid marks, and it is the soil - not stressed grass - that makes the stripes brown. Now this is also fairly scary! If the tractor is sliding down the hill, it is also not entirely under control until it stops its slide - even if it's sliding in a straight line! So, today I did some experimenting to see if I could do the hill without sliding. I came up with this:

1. Up the hill, 4WD, 1st Range. No sliding, no scuffing.
2. Down the hill, 4WD, 1st Range, BACKWARDS (w/FEL on and low), no sliding, no scuffing, stiff neck.

Anybody have a better idea? Am I safe enough? I didn't think the hill was that steep! I am forever grateful that I read about slope/pucker factor here before I got Thor and never tried to do that hill sideways!

Regards,

Jim

 

[Anonymous Poster]

Mowing is an activity that combines factors which tend to facilitate sliding on hills:
1. Tires that aren't aggressive enough to resist slides (R4's or turf type)
2. Heavy 3ph mowers.
3. Grassy ground that acts "greasy"

I follow certain rules to minimize sliding and damage to the turf:
a. stay in 4wd
b. mow the steepest parts by going uphill only
c. go downhill in the straightest line to the bottom; if you're descending at an angle, the mower will pull you sideways
d. if you lose traction and start sliding, do what's contrary to instinct -- accelerate the tire speed to equal the tractor's slide speed. ride out the "descent" by steering to a safe area and when the slope angle is less, slowly decelerate to pull out of the slide.
e. when going uphill or sidehill, use the differential lock on the rear wheels. however, avoid keeping them locked together when making turns, or the inside rear tire will do as much damage as any slide.
It takes time, trial-and-error, and repetition to figure out techniques to drive a tractor on hilly ground -- the trick is to minimize the penalties when you guess wrong.
jim

 

[Kodiak]

One more thing adjust your air pressure. A hard tire tends to act as an ice skate. so by lowering your air pressure you provide a larger foot thus more traction. However to little air pressure can make the sidewalls to flexible thus less stability. Its a trial and error thing, but it should help.