What causes tractor rollovers?

[Hay Dude]

I pushed it pretty hard today.
38,000lb square baler on a 16* incline had my butt pucker factor on about a 9 out of 10.
Tandems were locked and she was still angling downhill a bit.
If it went, it was a long way down until flat ground.
My biggest fear is the baler “gator rolling” me and tractor.

 

[M59]

I was using heavy equipment for paying my tuition and was driving a tractor when I was sent over to mow a steep hill near a school in the morning. Well, there was heavy dew so it was very wet and I slid down all the way to the bottom, over and over and I wonder how they managed to mow such a hill but I got it done. Well the next morning the assistant asked who had mowed that hill and when I raised my hand he went into a long "lesson" on the dangers of rollovers and how lucky I wasnt killed, and chewed out the one who sent me as he said you can never mow a hill when its wet or early morning, so my first lesson in tractoring..

Gravity combined with either Lack of Experience or Stupid or So Experienced that they push the limits.

 

[M59]

But there is always something that makes it reach the "tipping" point...

The Operator. See post 82

 

[5030]

In all my years of running ag tractors with loaders, I've never had any weight on the back unless I have an implement on but usually, nothing, but then I have common sense too.

 

[rocco611]

lots of good advice in this thread also keep your ROP in the up position, wear your seat belt.

 

[scootr]

If you are working with a FEL on the tractor be aware of how the height of the bucket changes your center of gravity. Also loaded tires decrease the chance of a rollover because they put additional gravity where it does the most good, down low. Which is where that bucket should be on a hill.

 

[Vigo327]

In all my years of running ag tractors with loaders, I've never had any weight on the back unless I have an implement on but usually, nothing, but then I have common sense too.

Seems to me like weight of the tractor goes up quicker than loader capacity, and they probably get more rear-heavy the bigger you go due to the wheels+tires. So there's a non-linear increase in safety factor just from those things the bigger you go. If you include tire fill it's a HUGE, almost exponential rise in safety as the tractors get bigger. For example, just going from a 1 series to a 2 series JD, 1025 vs 2025 etc, the amount of weight the rear tires will hold as fill goes up tremendously, making a tractor that's not much larger or heavier on its own, vastly more capable of safely operating at the limits of the front end loader. My B8200's filled 13.6-16 rear tires are almost holding more fill weight than what the loader on my smaller b6100 can even pick up.

I guess when you get up to a certain size point, cabs become sort of an assumption as well, but just as a point of reference, the cab on the tractor in your avator weighs more than the ENTIRE fel+subframe on my B6100.. cabs aren't ridiculously heavy, but they're not nothing either, and they're in the right place to make a difference.

 

[MHarryE]

Smaller tractors need rear ballast worst. Larger, tractor itself provides counterweight. The Kubota Grand L’s I had (3 of them) seriously needed rear weight. Moving bales, rear spear lift a bale first before thinking of front. M7 I now have, heaviest weight I loaded was a 6,000 pound book spec shop lathe that it easily lifted and was controlled (flat ground) and loaded onto a semi. Steering was very difficult so it was slow going but slow and safe. But my tractor, loader, and ballast is over 20,000 pounds vs. 6,000 - 7,000 range for the Grand L’s. Even my M5-111 at half the weight of the M7 can load bales safely without rear ballast, but you don’t have the comfort feeling of 10 ton tractor.

 

[npalen]

I have not personally tipped a tractor, but the times ive been nervous about it have all involved using the FELs.

Im guessing most people have concerns about slopes ive just never driven on the likes of. One thing I would say is we tend to form our first assumption of how tippy something is from how it looks, but tractors can be deceiving as far as their center of gravity. A lot of times the entire top half and sometimes more than that weighs very little and the actual center of gravity is somewhere vertically around or below the bottom of the frame. You as the operator are way above that so you become extremely sensitive to any sudden roll accelerations just because they are amplified by your long 'radius' from it, but usually get nowhere even close to tipping. You would start falling out of the seat before the tractor itself is in danger of tipping.

It's probably a good thing that things 'feel worse than they are' from the operators station just so that we're subconsciously more cautious.

The design software (ProE) that my company used would give the exact location of center of gravity and it was interesting to see how much a little weight change here or there would move the CG. I suppose it would be a stretch, though, to expect tractor manufacturers to publish this info not to mention all the aftermarket variables that affect the center of gravity.

 

[npalen]

What causes tractor rollovers?​

Tractor Drivers
Someday someone will tell me why people drive around with the bucket raised

I asked that question of a farmer and he said its for improved visibility such as in haying operations. I've seen it a number of times and also wondered why.