Tractor Sizing How much HP do I really need?

[Turbys_1700]

My New Holland 1720 was geared and at 28 HP would load up in the higher gears when traveling at any speed on the road. That was in high range in either 3rd or 4th which I consider road gears. At 28 HP and 3300# loaded it was doing all it could do based on it's small engine. Your Mahindra is doing all it can do with it's weight and HP rating. Go to a lower range.

 

[Roger66]

I think you are missing the point(s). The HST transmission is not like a car transmission. Tractors are not cars. They are not designed for high speed travel on roads. And, you are comparing a 4000lb ?200+hp Jeep 4wd to a 25hp small frame tractor???? Maybe you should have done some homework before making a purchase.

Island Tractor, Your correct, I should have done more research. My fault! As a first time tractor buyer there are so many things I did not consider. Until you get some real seat time many things you don't even know to ask. The high range lack of power is a example of the weak engine. To me the real problem is the low range issue. My example of pulling my truck out of the snow I was stalling the tractor in low range on wet snowy pavement without a function diff lock. IMO in low range stalling the engine before loosing traction is simply not enough power. Especially in the snow! Without a functioning diff lock!! I don't see how anyone can argue that.

 

[sd455dan]

Island Tractor, Your correct, I should have done more research. My fault! As a first time tractor buyer there are so many things I did not consider. Until you get some real seat time many things you don't even know to ask. The high range lack of power is a example of the weak engine. To me the real problem is the low range issue. My example of pulling my truck out of the snow I was stalling the tractor in low range on wet snowy pavement without a function diff lock. IMO in low range stalling the engine before loosing traction is simply not enough power. Especially in the snow! Without a functioning diff lock!! I don't see how anyone can argue that.

Is there any chance that you could trade up a size or 2 on the tractor? and also possibly (try) a manual with a shuttle shift?

If I read this right this is a virtually new , low hour machine under warranty? with a non functional diff lock.

Maybe talk to the dealer-if bought there and inform him of your frustration and disappointment in the performance power wise?

Living with a new tractor that is not up to your expectations is going to get old and possibly be a source of irritation every time you have to drive up that hill. I guess it comes down to whether getting used to a lower range for the hill is something you can deal with. (Or not)
I know (the Fred) had a problem something similar to this, Although His (solution) involved some radical surgery...

 

[Roger66]

Is there any chance that you could trade up a size or 2 on the tractor? and also possibly (try) a manual with a shuttle shift?

If I read this right this is a virtually new , low hour machine under warranty? with a non functional diff lock.

Maybe talk to the dealer-if bought there and inform him of your frustration and disappointment in the performance power wise?

Living with a new tractor that is not up to your expectations is going to get old and possibly be a source of irritation every time you have to drive up that hill.

I know (Fred) had a problem something similar to this, Although His solution involved some radical surgery...

I did just last night fix my Diff Lock, thanks to help from Dave from Dave Dave's Tractor, Inc. on another thread. As for up sizing, this tractor is physically the perfect size for me and I had enough trouble justifying this big of a purchase. On top of being afraid of the new emissions engines. Even my truck is a 2003 7.3L the last of the pre-emissions diesel trucks. I'll just have to learn to live within the limitations and/or figure out how to turn the power up on this one.

Thanks

 

[sd455dan]

I did just last night fix my Diff Lock, thanks to help from Dave from Dave Dave's Tractor, Inc. on another thread. As for up sizing, this tractor is physically the perfect size for me and I had enough trouble justifying this big of a purchase. On top of being afraid of the new emissions engines. Even my truck is a 2003 7.3L the last of the pre-emissions diesel trucks. I'll just have to learn to live within the limitations and/or figure out how to turn the power up on this one.

Thanks

that's good news,
Yeah Dave is one of the most helpful dealers and people on this site.

 

[Roger66]

that's good news,
Yeah Dave is one of the most helpful dealers and people on this site.

I'd buy my next tractor from him except for the the fact he's on the wrong coast!

 

[ericm979]

Roger, your tractor is working normally. Tractors are heavy and don't have a lot of power. Your 1533 weighs about as much as a mid sized car but instead of 200 hp or more it's got 25. CUTs aren't made to go up steel hills in high gear. My 7100 would barely make it up my steep 15% driveway in high range (of two) with the HST pedal barely cracked. It was really laboring to do it. My Branson won't do it in high range (of three) at all. It's high range is higher than the 7100's was. That high range is for road transits on flat or gently rolling hills. I don't have any of that. I've used it on the one 200 ft long section of flat road I have, just to make sure it works.

Your tractor does have a lot of pulling power. The weight that makes it slow up hills also gives it traction in the dirt. The engine does not have a lot of power but the gearing is low. If you're doing pulling in situations that the tractor was designed for it will do better than the pickup. Like pulling a plow, or logs out of the woods. But it's not going to haul a trailer at 45 mph up a highway hill like the pickup can.

 

[DavesTractor]

I'd buy my next tractor from him except for the the fact he's on the wrong coast!

Someone's on the wrong coast!

I remember the first HST I delivered years ago. The guy had a really step driveway. So I pressed the pedal down further and further. And I went slower and slower. As many have mentioned, that is like shifting up a gear, not shifting down. Fortunately I got my wits about me and let up on the HST pedal and pulled the throttle all the way back and up the hill I went, but not at 10 MPH. On most HST tractors, high range is for travel and not for much work, and going up a hill is work to some extent.

Let's say your tractor is 3200 lbs and 26 HP. You have 123 lbs to lug around with each HP. Take a new diesel pickup and let's say it weighs 7000 lbs and has 400 hp. Each HP has to move 17 lbs. So it is all about gears. We can't really compare a tractor to a truck.

However, your low speed issue seems like it should be looked at. If you were on the correct coast, I'd put your tractor on my dyno and see if it is putting out proper power first. If so and if it really did seems to lack power to the wheels, we would check the HST pressure ports to make sure the HST was working properly. To have a bad one is incredibly rare.

I hate to say this after all of your kind words, but I think some of this is getting used to how an HST works. Use the lowest range that will work for the task at hand, and within the range the more "pedal" the higher "gear" you are in, therefor the least torque available and the best chance to stall. Of course we can't get much done at 1 mph, so I understand there are practical limitations.

Thanks again for the kind words, and give that tractor a little more work with the concept in mind of how an HST works and report back please.

 

[Roger66]

Someone's on the wrong coast!

I remember the first HST I delivered years ago. The guy had a really step driveway. So I pressed the pedal down further and further. And I went slower and slower. As many have mentioned, that is like shifting up a gear, not shifting down. Fortunately I got my wits about me and let up on the HST pedal and pulled the throttle all the way back and up the hill I went, but not at 10 MPH. On most HST tractors, high range is for travel and not for much work, and going up a hill is work to some extent.

Let's say your tractor is 3200 lbs and 26 HP. You have 123 lbs to lug around with each HP. Take a new diesel pickup and let's say it weighs 7000 lbs and has 400 hp. Each HP has to move 17 lbs. So it is all about gears. We can't really compare a tractor to a truck.

However, your low speed issue seems like it should be looked at. If you were on the correct coast, I'd put your tractor on my dyno and see if it is putting out proper power first. If so and if it really did seems to lack power to the wheels, we would check the HST pressure ports to make sure the HST was working properly. To have a bad one is incredibly rare.

I hate to say this after all of your kind words, but I think some of this is getting used to how an HST works. Use the lowest range that will work for the task at hand, and within the range the more "pedal" the higher "gear" you are in, therefor the least torque available and the best chance to stall. Of course we can't get much done at 1 mph, so I understand there are practical limitations.

Thanks again for the kind words, and give that tractor a little more work with the concept in mind of how an HST works and report back please.

My John Deere LX255 Lawn tractor seems to have a really nice feature built into the hydro. I've towed super heavy loads with this little deere up that same driveway. On the deere you could mash the pedal to the floor and when the hill was encountered, the tractor would slow down, but still climb the hill. It appears there is some governor on the hydro swash plate that automatically "gears down" based on load regardless of the pedal position. On the Deere max pedal always delivered max power and max speed possible given the load. Never would lifting the pedal help. It would never ever stall. I've pulled such heavy trailers up that driveway that sometimes the tires would just break loose on dry pavement halfway up, but it would never stall. Clearly I need to learn how to lift as this tractor does not have this magic feature.

As for actually testing mine on a dyno, would an automotive dyno work? I know some race shops near by with dynos from my racing days decades ago. I would love to prove this one way or another.

Thanks

 

[DavesTractor]

My John Deere LX255 Lawn tractor seems to have a really nice feature built into the hydro. I've towed super heavy loads with this little deere up that same driveway. On the deere you could mash the pedal to the floor and when the hill was encountered, the tractor would slow down, but still climb the hill. It appears there is some governor on the hydro swash plate that automatically "gears down" based on load regardless of the pedal position. On the Deere max pedal always delivered max power and max speed possible given the load. Never would lifting the pedal help. It would never ever stall. I've pulled such heavy trailers up that driveway that sometimes the tires would just break loose on dry pavement halfway up, but it would never stall. Clearly I need to learn how to lift as this tractor does not have this magic feature.

As for actually testing mine on a dyno, would an automotive dyno work? I know some race shops near by with dynos from my racing days decades ago. I would love to prove this one way or another.

Thanks

I have no idea how a chassis dyno would compute with a tractor on the rollers. But it would make for a good photo op. Most all tractors dealers that sell and repair a decent volume of tractors will have a PTO dyno. Without it, there is too much subjectiveness. What feels gutless to one guy is a hotrod to another.

I suspect, based on the fact that we have sold 100's of the 1526/3016 tractors, that your power is ok and your HST is ok. The only time we see complaints on power with this model are when we sell a TLB and load the tires and put it up at high elevation. Now we are getting pretty heavy and have less air and going up hills in high range is not going to happen with that combo. Combine that with a new HST user and his first week or two can be disappointing until he learns to use medium range and to understand the tractors limitations.

Racing days in the past? It's not unheard of for a guy to put a turbo on a small diesel engine. But you then become your own warranty center, if you know what I mean.

 

[BrokeFarmerJohn]

My John Deere LX255 Lawn tractor seems to have a really nice feature built into the hydro. I've towed super heavy loads with this little deere up that same driveway. On the deere you could mash the pedal to the floor and when the hill was encountered, the tractor would slow down, but still climb the hill. It appears there is some governor on the hydro swash plate that automatically "gears down" based on load regardless of the pedal position. On the Deere max pedal always delivered max power and max speed possible given the load. Never would lifting the pedal help. It would never ever stall. I've pulled such heavy trailers up that driveway that sometimes the tires would just break loose on dry pavement halfway up, but it would never stall. Clearly I need to learn how to lift as this tractor does not have this magic feature.

As for actually testing mine on a dyno, would an automotive dyno work? I know some race shops near by with dynos from my racing days decades ago. I would love to prove this one way or another.

Thanks

Just did a little math, your LX255 has 15hp and 25.3 lb-ft, weights 483lbs, that's 19.32lbs per HP.

The 1526 has 26hp and weights 2440lbs, that's 93.84lbs per HP.

The Mahindra just pulling its own weight is doing 5 times more work then the garden tractor was but in high gear is traveling twice as fast.

Garden tractors don't have ranges, running a garden tractor with the peddle to the floor pulling a trailer is comparable to working the Mahindra in low range with the peddle to the floor, both traveling around 3mph.

I think your expectations for this tractor are WAY too high. I'm not sure where the expectation of zipping up hills in high range or that you could work it in high range going 10-15mph came from, I hope the dealer didn't lead you on in anyway.

Tractors do lots of work at low speeds, usually under 5mph. high range is just for travel, if it can't climb it in high, gear down to mid range, simple as that.

Your not gonna find a tractor that performs well in high range, your tractor climbs hills better than most from what I have read about the 1500 series Mahindra's.

For an example, I have a cabbed JD 4320, it's 48.1hp, my tractor with the cab and FEL weights around 5300lbs, that's 110.4lbs per HP, if I fill the rears or add more ballast that number will go up. If I filled the rear tires that would add 500lbs, if I added a ballast box another 500lbs, now were up around 131lbs per HP. The mindset of tractors is traction and torque, guys weigh there tractors down for better traction, we don't try to speed them up.

 

[Roger66]

I think we’ve beat this horse enough and I think we can close this thread.

As a first time tractor buyer, what I’ve learned:
My expectations were too high.
My test drive was not nearly comprehensive enough.
Don’t take anyone’s opinion on how much HP is enough, evaluate first hand on the test drive.
Less pedal yields more power on a basic Hydro unlike some lawn tractors like mine.
If the power is in question a PTO Dyno is the way to validate.
A 25 HP tractor can do lots of work, but the power is limited and must be used properly.
If you came from a “performance” Car or Truck background be ready for compromise.

 

[Shaneard]

I think we’ve beat this horse enough and I think we can close this thread.

As a first time tractor buyer, what I’ve learned:
My expectations were too high.
My test drive was not nearly comprehensive enough.
Don’t take anyone’s opinion on how much HP is enough, evaluate first hand on the test drive.
Less pedal yields more power on a basic Hydro unlike some lawn tractors like mine.
If the power is in question a PTO Dyno is the way to validate.
A 25 HP tractor can do lots of work, but the power is limited and must be used properly.
If you came from a “performance” Car or Truck background be ready for compromise.

Well said.

 

[Roger66]

I think we’ve beat this horse enough and I think we can close this thread.

As a first time tractor buyer, what I’ve learned:
My expectations were too high.
My test drive was not nearly comprehensive enough.
Don’t take anyone’s opinion on how much HP is enough, evaluate first hand on the test drive.
Less pedal yields more power on a basic Hydro unlike some lawn tractors like mine.
If the power is in question a PTO Dyno is the way to validate.
A 25 HP tractor can do lots of work, but the power is limited and must be used properly.
If you came from a “performance” Car or Truck background be ready for compromise.

I forgot to thank everyone for all of your participation in this thread!!! I also want clarify that I intend no fault to my dealer or the brand. My only real compliant is with the government imposed regulations. Even if one color or another has a few more or less Ft-lbs. of torque. I'm sure i would have had the same experience the whole rainbow at the 25HP power level, I'm looking for an order of magnitude more power not a couple of percent (if there even is a difference).

Thanks again all for your input!

 

[mike69440]

I think ideal ample power for a tractor gear type transmission is 1 HP per 100 lbs total weight, with a HST, 1 hp per 80 lbs of operating weight. (Tractor, attachments, and Implements) The ratio weight to HP can go up slightly for large tractors can go up slightly, except for heavy field work.

My L39 is slow turtle on hills roading at 40 Hp and 8000 lbs. Even fueled up a bit, and torquey for its power, 5 mph roading on a moderately steep hill is slow. I would be nice to pull near 10 MPH up a grade. Snow plowing needs power also. Field work needs power.

 

[CalG]

On 1.5 acres, 25hp will be more than enough tractor. things get crowded on a small place.

 

[AGTtactical]

I think ideal ample power for a tractor gear type transmission is 1 HP per 100 lbs total weight, with a HST, 1 hp per 80 lbs of operating weight. (Tractor, attachments, and Implements) The ratio weight to HP can go up slightly for large tractors can go up slightly, except for heavy field work.

I think this is the best bit of information in this entire thread. Interestingly, Kubota seems to agree. I built a spread sheet to compare my tractor choices, and every model (all HST) had a lbs/hp under 80...most were in the 65-75 range, before adding an implement or loader.

 

[searcyfarms]

so sorry about your situation with your tractor - that is what I call the most maddening thing that can happen - not enough power - I have had that sick feeling before when trying to go up a hill and then not being able to make it and then the empty pit in my stomach as I break into a cold sweat wondering how bad the wreck is going to be when I am upside down and stopped in the wreckage at the bottom, or when I crest the hill and didn't realize my load was bigger than my tractor weight and brakes combined.

I have to say I have only had one of those pucker events end up in a wrecked tractor/trailer of hay - the ole ford selectospeed - now sure the size of the tractor that it was in but the hay weighed more than the brakes/tractor could stop so we ended up for a wild ride with a spilled load, jackknifed tractor/trailer, and ford on its side. none of us were hurt but boy it scared the youth right out of us.

If you are trying to get firewood up the hill, be careful, the best advice several ole farmers gave me was be it a hill/mudhole - get a run at it!!! horses are smart they do the same thing!!!!

Are you smart or wise, the smart guy loads the trailer full and doesn't get there, the wise man makes more trips!!!

You will learn the abilities of your machine in each category of work, that is the beauty of it, you can still do a lot just have to plan accordingly - just respect the limitations and you will be safe.