Need advice on mowing a slope.

[jinman]

Re: Need advice on mowing a slope

if the rears are locked (because of brakes applied) on my tractor in 4wd the fronts are unaffected ...the fronts still have engine braking (if engine is running and tractor is in gear) which is why 4wd is a life-saver on steep slopes when the rears are "unweighted".

I hate to say I doubt you, so I'll just say that the mechanics of a 4WD system that can still drive with the rear wheels locked is a major bit of transmission magic. Can you tell me how that is mechanized? You would need two independent transmissions to do that. I truly believe you are mistaken, but I'll give you the benefit of the doubt if you'll please explain the mechanics of front wheels driving while the rears are locked. If that is true, there are lots of us here who will learn something by your description. If it is not true, you will have learned something. Either way we'll all be better educated.:thumbsup:

 

[flusher]

Re: Need advice on mowing a slope

Thanks for all the good advice! Below is a picture of the land before anything was done to it. I know it looks rough. The hill between the truck and the tree line is what still needs to be mowed. From the picture it looks like a gentle slope that could be mowed from left to right but it is steeper than it looks from this angle and this is the only picture I have right now. I will probably go this weekend and do the string distance excersize to get an idea of the exact angle. I just bought this piece of land and the tractor and my pucker factor is still very high. Besides that I don't much care for pain or a damaged tractor.

Hmm--high pucker factor.
You need to be careful and err on the side of caution since you're a newby when it comes to tractors and mowing slopes. If you've never had an "oh crap" experience with your tractor, the last place you want to have your first such sphincter check is while mowing a steep slope with a brush hog roaring behind you and your tractor going into a slide or a rollover. I assume you're at least 21 and fancy free, so the call is yours.

I don't have any slopes on my 10 acres of flat pasture, but if I did, I'd use my 1964 MF135 diesel to mow them



There's no substitute for low center of gravity and wide wheel track when tackling slopes.

Good luck. Just be careful out there.

 

[Smallplot]

Re: Need advice on mowing a slope

but I'll give you the benefit of the doubt if you'll please explain the mechanics of front wheels driving while the rears are locked. If that is true, there are lots of us here who will learn something by your description. If it is not true, you will have learned something. Either way we'll all be better educated.:thumbsup:

Just to add another question to confuse everyone, Considering your statement how do you explain independent brakes (brake assisted steering) while turning? I have used them many times but never thought about them effecting the front wheels. My understanding of tractor brakes is they only brake at the rear axle. I understand what you are saying but, the part that does not make any sense to me is when i am braking as i just described it would disrupt power to all tires equally due to the drive shaft which is not the case.

Good thing there is not a test to take to drive a tractor, i would never have passed it when i started driving tractors.. This is getting comm-plee-kay-ted for a farm boy. I think this section needs its own forum but it is interesting nun-the-less

 

[RoyJackson]

Re: Need advice on mowing a slope

Just to add another question to confuse everyone, Considering your statement how do you explain independent brakes (brake assisted steering) while turning?

I, personally, would not use steering brakes on a sloped area. Most, if not all, tractors have a method to lock them together...which is what I do.
About the only time I use the split brakes is when I'm plowing snow...keeping the tractor straight if it's pushed to one side...quick jab on the brake does the job.
Just don't see any advantage for split brakes, but I do see potential disadvantages if you're heading down slope and accidently hitting one brake.

 

[Smallplot]

The biggest factor to consider in the original question is operator experience. I think he believes he can mow the slope and based on his level of experience decided to call upon TBN to make up for his lack of experience. Considering that he has been given some very good opinions on the best method to tackle this chore. The hill pictured does not look very steep to those of us already having the experience to tackle such a task but could look like a mountain to someone else. (I might also add that it does not appear 300 feet long, or wide).
I would keep the loader on personally but either way would work, just would not try driving up the slope without it attached for the extra weight to balance out the mower, just keep it a few inches off the ground and use lowest gear until you get a feel for it. You may want to back up the hill one time without mowing just to get used to the feeling. Keep your mower higher than usual until you make sure there are no hidden blade breakers lurking. I would also walk each inch of what you want to mow just in case you may find a hidden ditch or other object. Go slow and enjoy the seat time.

By the way no one has mentioned this. If you do start to slide, don't keep the breaks locked up. You can apply then let off them if tires lock up to keep control of the tractor if it starts running down the hill with you (just like a car on ice). Locked up breaks equals no control while rolling tires equals a little control at least. Just be aware that you will be bounced around like a kernel of popcorn in a hot air popper and you will think you are breaking every land speed record known to man if you take a trip down the slope.

Yes I know this from experience. Had an AC jump out of gear once on me going down a hillside (it caught fire under the cab so I was also dealing with that while trying to keep it on all 4s.) and people lie if they say first you say it then you do it. It happens at the same time... just pack a change of clothes just in case... I had been up and down that roadway hundreds of times before that happened. It was a full sized field tractor and I believe I caught air going over some of them bumps that day. looking back I can laugh about it now but I do consider myself lucky.

 

[RoyJackson]

... just pack a change of clothes just in case...

Just dawned on me...I never realized so many TBNers have crapped their pants...

 

[Smallplot]

Just dawned on me...I never realized so many TBNers have crapped their pants...

I am certain about everyone has at some point or another. And as my embarrassed tale shows, it can happen at any time not just during the "hold my beer" moments. The tractor was a neighbors and I had just finished discing 45 acres. Unhooked and headed to the house. Had just started down the field road when i heard the pop and began seeing smoke coming from under the cab on the right side. Looked for the fire extinguisher only to find an empty bracket. My only option was to get to the bottom of the hill to throw some of the fresh dirt onto the fire. It had a partial power shift, I thought it went into the high side but slipped out between gears and began free wheeling down the hill. Trying to stop or slow down was useless besides every time I hit a bump, my foot came off the brakes as my head bounced off the top of the cab while the flames only got taller.

I was 21 at the time and it was almost 20 years ago but still remember it like it was yesterday

The morel of this story: It is safer to learn from another's mistakes than your own. And that is why TBN is so great.

 

[Scooby074]

Now that i see a pic I dont think youll have any trouble if you go straight up and down.

Id walk it first to make sure there are no pitfalls waiting for you.

 

[LD1]

I know a pic can be decieving, but it doesnt look too bad to me. I wouldnt have any hesitations mowing up and down that hill.

As to the brake questions that have been brought up, I'll try to explain....

The REARS are the only ones that actually have brakes. They are usually 2 pedals and can be locked together. Using individual braking is NOT good practice on hills. As Roy mentioned, it is benefical when plowing, or even using a rear blade on an angle, to keep the tractor straight.


So use the brakes LOCKED together and that will brake BOTH rear wheels. The rear wheels have an open differential. This is what allows you to be able to use only one brake (if unlocked) and still allow the other wheels to spin.

Your front wheels ALSO have an open differiential. So...both axles have an open diff's. BUT, there is NO differential between the front and rear axles. SO, if the back brakes are pressed, this effectivally brakes the driveshaft running to the front axle IF 4wd is engaged. Thus, even though the fronts dont actually have brakes, they are still helping the tractor to slow down through the mechanics of the 4WD.

Heck, even most rear wheels dont have brakes on newer tractors. They are inboard brakes that actually brake the axles, which inturn brakes the wheels. Same principal.

 

[jinman]

Re: Need advice on mowing a slope

...Considering your statement how do you explain independent brakes (brake assisted steering) while turning? I have used them many times but never thought about them effecting the front wheels. My understanding of tractor brakes is they only brake at the rear axle.

When you step on one rear brake only, the rear axle differential allows the opposite wheel to turn and be powered by the drivetrain in a normal manner except it is turning at a higher speed due to the differential action. The drivetrain and transmission see no difference to normal non-braked operation. When you stop both rear wheels, the differential cannot work and thus the drivetrain through the transmisson and to the engine is locked. If you are driving a gear tractor with the clutch engaged, you'll stall/kill the engine unless you press on the clutch to release the engine and allow free rotation. This will happen in a 4WD tractor or a 2WD tractor.

Because the front 4WD is driven off the transmission's final drive through the transfer gearbox. It doesn't feel the effect of one rear wheel locked, but when both rears are locked and the transmission is locked, the driveshaft to the front wheels is locked and cannot rotate. Then, the front axle's differential comes into play. The front differential will stop the wheel with the least rolling friction and allow the other to turn through normal differential action. Thus, with both rears locked and the tractor in 4WD, one of the front wheels is locked so that only one front wheel is turning. If you have a front axle differential that locks up or has limited slip, then all four wheels will stop. This is the effect of 4-wheel brakes through the 4WD driveline.

On HST tractors, the secondary part of the transmission is a gear transmission. That's the part that allows you to change drive ranges (Hi-Med-Lo) or some tractors only have two ranges instead of three. In front of the gear transmission is the HST transmission. Therefore, if the gear portion is locked due to both rear wheel brakes being locked, the HST transmission will go into pressure bypass and the engine can still operate, but the torque is not transmitted to the rear transmission. The HST relief valve essentially works as a torque "fuse" to allow power to bypass the rear transmission and drivetrain.

So to summarize, you can do differential steering with the brakes on any kind of tractor because the rear differential will allow the transmission to work normally for one wheel. However, once you lock both rear wheels, the transmission is fully locked and the drivetrain will stop all the way up to the engine unless the clutch is depressed or the HST transmission goes into relief bypass.