Updated March 2018. I read many reviews complaining about lawn tractors not being able to mow on a hill. “They don’t have enough traction.” “I have to use tire chains.” “I have some fairly steep hills on the property and the tractor stands so tall that it is not safe at all on hills over 15 degrees. So I couldn’t mow half of my lawn.”
It’s time to stop complaining and get real. You will not be able to mow all of your lawn with a lawn tractor or zero-turn if there are slopes.
Thank You Toro For This Photo
The truth: Residential Lawn Tractors and Zero-Turns are not designed to mow on slopes steeper than 15 degrees. They all tell you that in the manual. There are mowers designed to mow hills but the cheapest one on the market is over $10,000. The good ones are in the $20,000 to $50,000 range.
Making myself more comfortable on a slope is not my goal. Not rolling the tractor or zero-turn is my goal. Rolling the tractor is not worth cutting an extra bit of grass. It is just grass.
If it is too steep to mow, turn it into a landscape bed or wildlife area.
Be Safe:
- On steep slopes, GO SLOW.
- Sidehill mowing, watch the front uphill tire to verify it’s making a solid depression in the grass. If it isn’t, SLOWLY turn downhill.
- Always have an escape route when mowing or traveling over rough ground so if the machine kicks out of gear or the brakes fail or both you can steer to safety.
- Keep the brakes properly adjusted and maintained.
- Be very, very aware that going up a steep slope how quickly and easily a tractor will flip back on you. If the front end does come up, the rear wheels provide the motive force to flip it back.
- Generally speaking, brakes are for stopping, NOT slowing down in tractor usage, that’s what the trans is for. If you step on the left pedal you set the parking brake and the rear wheels will lock. In most cases this will not hold you on the hill, instead, you will slide down the hill.
- The “GO SLOW” mentioned above means regulate your speed with the transmission. Choose a lower or lowest gear, with a hydro, do the same, keep the RPM’s (engine speed) up.
Can a tractor mow this hill? NO!
Zero-Turns are not weighted to mow up a hill. Especially older zero-turn mowers. They will tip over backward.
- If you cannot back up the slope or if you feel uneasy on it, do not mow it with a ride-on machine.
- Mow up and down slopes with a lawn tractor, not across.
- Watch for holes, ruts, bumps, rocks or other hidden objects. Uneven terrain could overturn the machine.
- Choose a low ground speed so you will not have to stop or shift while on a slope.
- Do not mow on wet or damp grass. Tires may lose traction.
- Do not mow on drought-dry grass. Tires will lose traction.
- Always keep the machine in gear when going down slopes. Do not shift to neutral and coast downhill.
- Avoid starting, stopping or turning on a slope.
- Keep all movement on slopes slow and gradual.
- Use extra care while operating the machine with grass catchers or other attachments; they affect the stability of the machine. Do not use them on steep slopes.
- Do not try to stabilize the machine by putting your foot on the ground.
- Do not mow near drop-offs, ditches or embankments.
46 inch 2 blade decks on lawn tractors do not have the clearance between the rear of the deck and the rear tires to install tire chains.
If you have a Walk Out Basement the angle is too steep to mow side to side or up the hill. Mow down the hill, drive around to the top of the slope and mow down. Yes, you may have to drive around the house a dozen times to do this, but it is the only way. Never attempt to mow or drive up the hill
Don’t even consider using a rear mounted bagger on hills. On both tractors and zero-turns that makes them too heavy in the rear.
Don’t even consider a leaf/lawn vac on slopes. The transmissions in lawn tractors are not heavy enough and you will destroy the trans. On garden tractor, there may be too much weight on the rear hitch. Blow the leaves to the bottom of the hill with a handheld blower or backpack blower, then pick them up with your vac.
Tip-over from water logged turf
Do not mow near drop-offs, ditches or embankments. Don’t mow near a pond. The first 6 to 10 feet of turf by the water’s edge is water-logged and your mower will sink in and tip over.
Follow the rules in your operator’s manual. But remember, an unseen hole on the down-slope or a bump or stick of wood on the uphill side can increase your slope quickly and cause an accident.
Seatbelts and ROPs won’t save you if there is water
What is available today For the Homeowner:
Notice the dual wheels on the ATV?
The ATV is out of the water logged turf
There are very few residential mowers specifically designed to mow slopes. Here are a few that work:
Acrease Wing and Rough-Cut Mowers: Acrease Mowers are able to mow slopes. They use full pressure engines on the commercial models that won’t blow up on slopes greater than 15 degrees. Be aware these mowers are heavy and you will need a heavy tractor to pull them. I actually used 2 in tandem to mow a 10-foot road ditch 
(Swisher T-60 Trailmower 14.5hp. is only designed for 15-degree slopes. The engines are splash lubricated and will blow up on slopes greater than 15 degrees.)
Craftsman 4WD walk-behind.
Husqvarna:
Walk-Behind Husqvarna HU800AWD All Wheel Drive
There are a few tractors with a rear differential lock from Craftsman Pro, Cub Cadet and Husqvarna that give you better traction going up and down slopes, but they are still only rated for 15 degrees.
There are other mowers that will handle slopes but all of them are commercially rated. Standon Mowers, 60 inches and larger like the Wright Stander are capable of mowing greater than 15 degrees. Toro Walk-Behind commercial mowers with the T-Bar steering also work well. Of course, there are the dedicated slope mowers like the KutKwick and the new robotic mowers.
Final Thoughts
Many people don’t read the operator’s manual or feel these warning statements are “just guidelines.” Even staying under 15 degrees there are still ways to tip your lawn tractor or zero-turn mower over. Mowing commercially for many years I have had too many close calls and I still use my “Pucker-meter” all the time. The seat of your pants is the best gauge – really. It is a long, slow, careful learning experience. You have to get to know your machine and how to best approach various terrain. Going slow and low is always good.
If is feels wrong, if the hill feels too steep, if the tractor doesn’t feel right, I don’t mow it.
(This Last From Consumer Reports)
What we tested, what we found. We compared several zero-turn-radius riding mowers marketed to consumers with a lawn tractor on slopes ranging from roughly 5 to 20 degrees. We used a typical 4.5 mph mowing speed over both dry and wet grass, going up and down as you should with most ride-on machines. So far, so good.
The trouble began when we made a hard turn down 10- to 15-degree slopes. The zero-turn riders lost most of their steering control, skidding straight into our simulated hazards. All could stop in time when the brake was applied, though stopping entails manipulating two levers that also do the steering. That’s less intuitive than a tractor’s foot brake. And while the zero-turn models steered controllably at slower speeds, time savings is a major selling point for zero-turn machines.
The rollover risk
Rollovers are another concern with all ride-on mowers, contributing to the more than 15,000 injuries and 61 deaths associated with those machines for 2007, according to estimates based on CPSC data. Commercial tractors and riding mowers often include a roll bar, called a rollover protective structure (ROPS), and a safety belt. Both are supposed to work together to protect and confine the operator if there’s a rollover. But even that approach leaves lots of room for error.
- Choose a front-steering tractor over a zero-turn-radius rider if you’re mowing slopes 10 to 15 degrees or greater. (A 10-degree slope rises roughly 20 inches over every 10 feet.) If you already own a zero-turn-radius riding mower, be sure to mow slowly on hills. And mow only on dry grass to maximize traction.
- Give yourself time to learn the controls on any ride-on mower, especially a zero-turn mower’s levers for steering and speed.
- Mow straight up and down slopes with a tractor or rider unless the manual says otherwise. And mow side-to-side with walk-behind mowers, start at the bottom and work up-hill. Always turn uphill.
Grax McCoar
I wish I’d had your discussion here when my ex-husband was certain he could mow our 5+acres using a “lawn tractor” with the cutter mounted underneath. It was designed for flat lawn – wheels too small, not enough clearance underneath, cutter ‘designed to’ pick up sticks & rocks and wedge them between the blades and housing. Also baler twine, concealed ancient feed sacks, and electric fence wire mostly buried in the weeds. What was being mowed was haygrass pasture, lightweight but tough brambles and brushy groundcover, mostly on a 15degree or steeper slope. The only reason it didn’t tip over on him was that it was short, wide and kind of flat – it got itself stuck with one side up in the air instead, and had to be levered upright again. He didn’t think I could understand (what was wrong with) his technique and didn’t listen to me. If I could have shown him what you have to say here he’d have given up on the mower and I could have had the scaled down sicklebar walk behind that I’d asked for and taken over the mowing.
Charles Beaverson
Hi Paul….just double-checking. I think you said all Kohler engines have oil pressurized engines. I have a John Deere L-110 and used it on many inclines. It has held up wonderfully and never had engine problems due to not getting oil. I’m assuming that’s because I have a pressurized engine?
Paul
Hi Charles, Your L-110 uses a Briggs & Stratton pressurized engine block.
Ronald Park
Paul,
Nice article. I have a small lake/large pond on my property with an earthen dam about 150 ft long. I run a mower across the top of the dam, but it does slop severly (nearly45) down into the water. We have various weeds and even small saplings that grow there as well. The pic on your article shows a pull-behind mower for such a slope. DR Power only supports a 22-degree slope. Where do I find that mower?
Paul
Hi Ronald, that mower is made by Acrease.I recommend the rough-cut model. It costs more than a DR or Swisher but it will last you years and years.
Tell Matt Kunz I sent you, what you are going to use the mower for and he’ll help you get an engine that will last on your slopes. Here is a link to the rough-cut page: Acrease Rough Cut Mowers
MiserableOldFart
I routinely mow steep slopes with my Kubota Gr2120 lawn tractor. Its all wheel drive handles up and down slopes exceptionally well. I can rant and rave about the problems I’ve had with this machine, but on hills, as long as you have a flat spot to make your turn, it’s phenomenal.
Mark
Thanks, I was contemplating taking my riding mower down an identical slope that you have in the picture. So glad I saw your article I think you may have saved a trip to the emergency department.
Chris
Hi Paul,
This page has been a great wealth of knowledge especially for my situation. I have 7 acres with several large slopes (easily 20 degrees). Each an acre + in area. Currently using a Kioti cs2210, which I mow up and down. What are your thoughts on the Altoz TRX. Are the tracks style zero turns any benefit to working on slopes. I have also been considering the cub cadet Pro z 972 SD.
Paul
Hi Chris, the best sidehill mower on the market is the Kut Kwick Slope Master. I really like the tilting seat on this mower and I’ve spent many hours on one.
The second best is the Ventrac 4500 TRACTOR with duals. The 4500 has the ability to do more than just mow your hill.
The third best is the Wright Stander ZK. By standing you can shift your weight to help with traction and if you get in trouble all you have to do is step off the mower and get away from it.
Also in third place is the PRO Z 972 SD. I really like the steerable front wheels and the extra weight in the front rims so it will hold slopes very well. It’s a very good choice.
The Altoz TRX is really designed for soft and rough ground. Altoz shows it mowing hills but they really haven’t given any data of what slopes it will handle. If you get it I would suggest the all-terrain tracks over the turf tracks. The Altoz TSX on the other hand will be a good choice for hills. A standon is a lot less tiring than a sit-down mower on slopes.
Natalia Munoz-schneier
Hi Paul,
Great blog post. Very informative. I’ve been looking into getting a riding lawn mower to lower my overhead of maintaining our property. Everything out there says similar to you that 15 degrees is the max for mowing, but what about just riding? My issue is that our property is very sloped and I need to get from the lower level (where I’d like to store the mower) to the upper level (where there is actually flatter land to mow) and to do so, I’d have to go up our driveway, which is steeper than 15 degrees for sure. Is it safe, if not mowing, to ride up on an asphalt paved driveway? Say on either a Craftsman 110/140 or T100/110? Thanks in advance for any advice you can give here.
Paul
Hi Natilia, Yes, going up your driveway with a lawn tractor will be fine. Just be very careful turning on the steep part of your drive.
You may want to consider spending a few hundred more and getting a mower with a heavier-duty transmission. The tranny in the T100 series is very light duty.
Take a look at this Cub Cadet: XT1 LT42 with IntelliPower™
Titan415
Hi, Paul. I have a Ryobi Zero-turn and wish I’d read this article before I bought it. My land has some steep inclines, and I try to mow down the steepest ones.
One thing I’ve done that I haven’t seen anyone suggest is add 55 pounds of weight to the front, which is helping to keep the front wheels down. Why, I wonder, isn’t anyone recommending this?
Paul
Hi Titan415, What I’m about to write is going to seem like I’m yelling at you. PLEASE don’t take it personally…
Adding weight to the front end of a ZTR is very dangerous! If the ZTR will not mow the hill – you have the WRONG mower for the job.
1. Zero-turn mowers are designed to mow slopes less than 15 degrees. Lightweight, residential zero-turns like the 42 inch Ryobi, Troy-Bilt, Craftsman should NEVER be driven on slopes greater than 15 degrees. Smaller 30-34 inch ZTRs should never be driven on slopes greater than 10 degrees. Why? Because they are too light and trying to mow steeper slopes will cause them to slide down the slope or become unstable. You can easily tip one over when it’s sliding and it hits a bump or pothole in the lawn.
2. ZTR’s are balanced so you have traction in the rear because that’s where all the turning occurs. Adding weight to the front end causes you to lose traction in the rear. While you may not notice it going up a hill – going down the hill is when all the problems occur. With less traction in the rear, the rear wheels can’t get enough traction to turn the mower at the bottom of the hill. If there is a pond, fence tree, etc. in your path you may not be able to control the ZTR to make the turn. If you try to turn the mower before the bottom of the hill the rear will fishtail and you’ll end up sliding sideways down the hill uncontrollably. This is aggravated by wet grass or drought-dry grass.
There are very few things scarier than riding an out-of-control ZTR down a hill headed towards a fence, drop-off, or pond!
3. With the added front weight the ZTR won’t turn in soft soils. Light, sandy soil especially. The front casters won’t swivel and the rear just digs into the turf.
The ONLY time weight is added to the front of a ZTR is when you are offsetting the weight of a rear bagger.
I’ve been using ZTR’s since they came out in 1993. I’ve put thousands of hours on them and have owned everything from a 30-inch DIXON to a $50,000 Kut-Kwick. I’ve had all the problems with various ZTRs over the years I just talked about and worked with engineers to get these mowers as safe as possible. But, they all still have limitations and won’t work for everyone – especially residential models on hills.
Titan415
Thank you for the reply, Paul. I’ve been very concerned about all the things you mention, and mowing this yard does make me uncomfortable. Unfortunately, I’m not sure what to do about it. I’ve given some thought to hiring a welder to add a roll bar, just so i have some protection. The weights do seem to help keep the front wheels on the ground, though, so I’m not sure what to do.
Dave
I’m looking for a self-propelled push mower to help with a portion of my lawn which is probably 25 degrees or so, with a budget of about $1200. I know the recommendation is to mow side-to-side, but what I find is that the mower slips/veers way too easily downhill, and if I push it upward diagonally to maintain the proper height while moving across the hill, then it’s skidding quite badly and ripping up the grass constantly.
Are there any mowers that have wheel brakes which could be used to make going straight down the hill safer and easier?
Paul
Hi Dave, NEVER go down a steep hill with a walk-behind. You could slip and you’ll end up under the mower. About the only walk-behinds that would “brake” going downhill are the commercial hydro mowers. They start about $3000. BRADLEY 36″ HYDRO WALK-BEHIND MOWER T BAR BRIGGS
Dave
I measured the slope and it’s 22 degrees. Going side-to-side, I’m finding it very problematic to control the sideways slide downhill which basically just rips up the grass. Would an all-wheel drive mower help a lot with that? Or maybe just the grass variety (mostly cereal rye) is making it worse? Would appreciate any thoughts on making the side-traversal a bit better…
Paul
Hi Dave, I’m going to guess you want a walk-behind. That slope is too steep for a riding mower or ZTR.
Yes, an all-wheel-drive will make a big difference. The best one right now is the Toro Recycler 22 in. All-Wheel Drive Personal Pace.
If you have a larger area to mow another option is a wide-area mower. They are heavier and will hang on the slope better. Be sure to buy one with non-castering front wheels. Here is an example: Toro TimeMaster 30 in.