4X4 downhill traction issue

[Creekpaddler]

I recently picked up a Simplicity Prestige AWD tractor.It has turf tires on it now and climbs steep grades up to 30 deg even with open carrier differentials.But,downhill runs produce sliding and runaway conditions.I'm putting aggressive ATV type tires on it and debating whether adding fluid to the tires would help any on the downhill runs.Thoughts?

I had the same problem with my John Deere LX188 2WD HST lawn tractor. My hill is a 25% grade. I put ATV tires on the tractor to give it traction for climbing my hill when the grass gets too slick for turf tires. Bu the ATV tires didn't completely stop the downhill sliding. What does work for me is to slowly back down the hill in reverse without using the brakes. I hope that helps.

Experience has shown me that weighting the rear wheels does not prevent a downhill slide. My JD 5225 4WD utility tractor with weighted rear wheels will slide if the slope is steep enough.

 

[locknut]

Looking at your one photo, the hill looks pretty steep. You might want to check some of the websites that compare degrees vs percent slope. A 30% slope can be handled easily by many 4wd lawn tractors. My Kubota Bx 2200 would be fine with that and I mow one that steep every week. A 30 degree slope is a much different situation. A 30 degree slope is nearing 60% and VERY few of the 4WD lawn machines can climb it. Most are hydrostatic and (even in low range) the hydrostatic will probably not pull a 30 degree slope regardless of traction. They are much more likely to hum than to pull the hill. But back to your basic issue -- if locking the differential works, use it. If the tires still slip, your only serious alternative is chains. And if you have to put on chains to mow some grass your are simply barking up the wrong hill. Smartest thing to do is stay off it if you cannot mow it in reasonable comfort and control. My opinion of course. Those are the only opinions I have -- mine !

Slopes don't photograph well.They always look much milder.There are basically three 4WD lawn/garden models on the market.The Kubota GR has a weak hydro and won't climb over 10-12ft up a 30deg slope and stalls out.Very safe going downhill though,as the rears are locked and the shaft driven front axle provides excellent holding action.I've gone down this hill after 3in of rain,ground is muddy and tall,wet grass.Sticks like glue.Bar tires not filled.The second entry is the one I'm working with now,the Simplicity Prestige.The K664 mid-level hydro is much more robust and will pull up this 30deg slope dragging the 192lb deck like it's nothing.Going downhill,the hydraulic front drive has very little holding power so the front wheels just roll along for the ride and the rear open differential goes into it's counter-rotate mode,so essentially the entire machine has only one rear wheel providing holding power going downhill.This starts at about 20deg.The engineers that signed off on this tractor should be ashamed.The other entry is the X7XX Deere tractor which is very robust in the hydro dept and the hydraulic drive on the front is designed to hold traction much like a shaft driven setup.Slopes like this should be no problem,up or down,with the Deere and side hilling should be much better with a wheel track approaching 4ft,compared to the GR at 39" and the Prestige at 37-1/2".BTW,none of these tractors have a dual range drive,only single speed hydros.

Another thought.On a 30deg slope approximately 250lbs is transferred off the back and planted on the front wheels.This is where the traction can be found.I'll have all the components for the front brake system this week and will post progress reports with pics and observations.

 

[Nooodles]

I recently picked up a Simplicity Prestige AWD tractor.It has turf tires on it now and climbs steep grades up to 30 deg even with open carrier differentials.But,downhill runs produce sliding and runaway conditions.I'm putting aggressive ATV type tires on it and debating whether adding fluid to the tires would help any on the downhill runs.Thoughts?

adding fluid to those tinytires is gonna ad what? 30 pounds maybe? that wont do crap. You need to put chains on those tires and lower the air pressure to where they are squatting kiddo

 

[Edward. S]

adding fluid to those tinytires is gonna ad what? 30 pounds maybe? that wont do crap. You need to put chains on those tires and lower the air pressure to where they are squatting kiddo

Yes everyone, lets mow grass with chains on the tires, also I don't have radials so lets just put 2 pounds of air into the tires, and damage the tires forever. At least that 30 pounds of deadweight is more useful than your brain.

I would get the ATV Tires, then fill with Rim guard, or any other fluids. Rim guard wont damage your rim where as calcium will.

 

[94BULLITT]

adding fluid to those tinytires is gonna ad what? 30 pounds maybe? that wont do crap. You need to put chains on those tires and lower the air pressure to where they are squatting kiddo

Rim guard would add 77lbs a tire.

 

[jrdepew]

I'm not sure how much area this hill takes up...but I have a small toro walk behind mower with variable drive speed (increased push from the operator makes the wheels turn faster....very handy) It has a pressurized oiling system and I do very steep banks and ditches with it all the time, stuff that would be suicide with a riding mower. Start at the bottom, let the mower climb up, then back down at your own pace. Safe, cheap, and won't chew the yard up at all. I whoop that mower pretty hard and it has started on the first or second pull every time for 5+ years now. Got it from a local Toro dealer, not a big box store.

Joe

 

[Gale Hawkins]

R-1 and R-4 tires need to be mounted in the opposite direction to hold well going down hill but then they would not hold as well going up hill.

We use our DR Field and Brush walk behind bush hog just fine on 40+ slopes. If you take your hand off of the handle it stops pulling. I do NOT like going up steep grades as well as down because if control is lost there I have little control in a skid.

 

[locknut]

The carnage to me is just about all healed up. The wreaked tractor is totally dismantled and on its way to be a small fork lift. How ever I will document the fork lift build. If it is a simple matter to put the pictures on here I will do that to. Mac

Mac,nice to hear you're mending well after the accident.With pictures,I've used Photobucket for quite a while now and seems to work well and it's free.Uploading pics from the computer is easy and if it crashes all your pics are saved on the site.Downloading to a site like this is just a one click operation.What tractor are you adding brakes and how is that coming along?

 

[bubbacuse77]

I go up and down some steep hills on my x749 and never use the differential lock. I think the hdap tires are very helpful in maintaining traction so changing out your turfs should help alot. On your Simplicity do you have mfwd or hydraulic? I ask because I went to the Simplicity site and the spec sheet didn't have much info.

I second this, you need better tires like on the x749. I have a hill just like yours and tried both a JD 728 and a simplicity AWD my neighbor has. I ended up with the JD x749 but I was thinking at the time that the traction was much better with the JD because of the tires. Was it just the back tires slipping or where the fronts slipping as well?

 

[locknut]

I'm not sure how much area this hill takes up...but I have a small toro walk behind mower with variable drive speed (increased push from the operator makes the wheels turn faster....very handy) It has a pressurized oiling system and I do very steep banks and ditches with it all the time, stuff that would be suicide with a riding mower. Start at the bottom, let the mower climb up, then back down at your own pace. Safe, cheap, and won't chew the yard up at all. I whoop that mower pretty hard and it has started on the first or second pull every time for 5+ years now. Got it from a local Toro dealer, not a big box store.

I've used a self-propelled mower on this hill in the past.Worked good on the lower part where you could get good footing but as you went up to the full 30deg part the mower would slide down sideways and was hard to keep good footing.The bank is 115ft from one side to the other and 18ft up in the center.When weedeaters came into being several years ago we stopped trying to mow it and just trimmed it.But,as I got older it became too hard on my feet and ankles,plus the frequent faceplants when losing footing,so I decided to get a machine to ride up and down and mow it.So far it's worked out well but still takes 100% concentration and faith in the machine that it doesn't fail mechanically.My B-I-L used to help with the mowing until he lost footing at the top and yanked a push mower up over his foot and almost cut it off.

 

[bcp]

Remote controlled tracked mower:

Remote+Control+Slope+Mower



Bruce

 

[Tony M]

That looks like a great idea, Bruce. However, even these are not idiot-proof. A couple of years ago when i was researching slope-mowing solutions I looked into the remote-controlled gismos and found a story about an operator downhill of one getting killed when it lost its traction and fell down the hill collecting him on the way.

I try to err on the side of caution in deciding when to mow up and down or across the few steep slopes on our property - a couple of areas get the brush-cutter treatment even though they could probably be safely mowed with either the JD 3270 or the Greenfield rideons. It's just too easy to underestimate how wet and slippery the grass is or to dip a lower wheel into a bit of a depression that changes the side angle more than expected.

 

[bubbacuse77]

Remote controlled tracked mower:

Remote+Control+Slope+Mower





Bruce

Great, Drone lawn mowers. How long until we go completely autonomous and then one day the machines take over. Didn't you all see Terminator? :laughing:

 

[locknut]

Yes everyone, lets mow grass with chains on the tires, also I don't have radials so lets just put 2 pounds of air into the tires, and damage the tires forever. At least that 30 pounds of deadweight is more useful than your brain.

I would get the ATV Tires, then fill with Rim guard, or any other fluids. Rim guard wont damage your rim where as calcium will.

LOL reminds me of an old Mark Twain quote...." Better to keep your mouth closed and be thought a fool than to open it and remove all doubt".

I already tried the ATV tires,then I put some Firestone Floatation 23's on and those worked better but still slides.Brake project in progress.

 

[locknut]

Thats too bad locknut...was hoping the new tires would give you enough "bite" to slow down, but if wheel is basicly freewheeling, no amount of "bite" is gonna help. With your fabrication skills I am quite sure you could design some brakes for the front wheels, then you could move forward and use each machine as you planned.....I suspect it ,might be a pretty major project though. I do agree.....if you didn't have slopes in excess of 10% you wouldn't need 4WD in the first place.......I feel a long letter comeing for marketing and R&D (not that it would help).........

Should have all the parts for the brake project this coming week.Put the loader on the GR with the cab main frame/roof for a little shade.Drove around the property and trimmed all the low hanging branches that hit me in the face when mowing.Sure is easier using the loader than cutting/dragging all the stuff to one spot by hand :cool2:

 

[JWR]

Loaders are SO useful on any size tractor. No less so on a lawn mower. Is that a factory loader or one adapted to fit ? I'm somewhat surprised you found the hydraulic connections and pump capacity to let you do that. Certainly worthwhile.

 

[locknut]

Loaders are SO useful on any size tractor. No less so on a lawn mower. Is that a factory loader or one adapted to fit ? I'm somewhat surprised you found the hydraulic connections and pump capacity to let you do that. Certainly worthwhile.

The loader was custom designed by me and a local fab shop did the welding and made the bucket.It's 12V powered with 18" actuators on the arms and 12" on the bucket.Control is an arcade joystick hooked to 2 reverse-polarity solenoids.Everything comes apart using pins and bolts w/welded nuts.It hangs on the wall when not in use.Pretty slick.More pics;

http://www.tractorbynet.com/forums/...63-my-little-gr-thinks-its-2.html#post1781018

 

[RaydaKub]

That is really clever thinking. Nice job.
I would guess that your average 7 yr old probably would run it better than you however. :laughing:

 

[JWR]

Now that IS slick !! Maybe you ought to patent some aspect of that.

 

[Edward. S]

LOL reminds me of an old Mark Twain quote...." Better to keep your mouth closed and be thought a fool than to open it and remove all doubt".

I already tried the ATV tires,then I put some Firestone Floatation 23's on and those worked better but still slides.Brake project in progress.

I like that quote! Thanks for sharing it.