Tractor Sizing TRACTOR WEIGHT as ONE (1) CRITERION in TRACTOR SELECTION

[jeff9366]

Searching for buying advice on garden tractor, with 3 pt, rear PTO, strong enough to plow, no need for mower.
Can be used, or new.

Kitchen garden, 1/4 acre. Been plowed and disked before, have brinly hardy 10”plow on craftsman gt 5000. Hard to get enough traction to plow smoothly. Has tractor treads, ballast, and weights. Almost bearable. Same brand disc. Craftsman GT 5000 has no hydraulics, or 3 pt.

Craftsman GT5000​

2009 - 2010 GT5000 Series Garden tractor Husqvarna built

Weight

644 lbs 292 kg

The fundamental importance of TRACTOR WEIGHT eludes many tractor shoppers. Tractor capability is more closely correlated to tractor weight than any other single (1) specification.

The median bare weight of subcompact category Three Point Hitch tractors is around 1,400 pounds. Unfortunately, you have to pay for every pound.

Very few subcompact category tractors are sold without 4-WD and a two range HST transmission.



VIDEOS:

https://www.youtube.com/results?search_query=sub+compact+tractor+plowing

 

[workinonit]

I'm gonna play devil's advocate and disagree with you to some extent. You are 100% correct and then you aren't. Personally, I buy a tractor by HP. My logic is when HP increases the weight always increases for typical tractors. Therefore, I believe HP and weight are equally important when choosing a machine. And if you consider the intended use I believe there is another equally important consideration and that's 4WD. If you are buying a machine for ground engaging equipment I think 4WD is essential and just as important as the other two. But for me personally, I didn't consider any tractor that didn't have a cab. That was #1 for me. Bottom line is you can beat that weight drum to death but some of us don't really specifically take weight as a condition for a purchase.

 

[Torvy]

HP and weight do not directly correlate. Most brands sell 2-4 HP options on the exact same frame. HP goes up, weight stays the same. Some brands are lighter across all HP than others. Kubota, for example, JD for another. Probably due to their superior materials and workmanship. However, Jeff is not wrong that weight improves traction and stability.

For me, it is a both-and, not an either-or situation. Need good HP and decent weight to apply that HP.

 

[rScotty]

HP and weight do not directly correlate. Most brands sell 2-4 HP options on the exact same frame. HP goes up, weight stays the same. Some brands are lighter across all HP than others. Kubota, for example, JD for another. Probably due to their superior materials and workmanship. However, Jeff is not wrong that weight improves traction and stability.

For me, it is a both-and, not an either-or situation. Need good HP and decent weight to apply that HP.

Jeff is invested in weight as the solution to traction. All solutions are trade offs. Weight works to increase traction, but the downside is that extra weight still requires takes energy to move around whether the extra traction is needed or not. Stability? Maybe, but a little extra wheel width gives more of that.

A lightweight tractor with 4wd would have the same traction as a heavier 2wd...but the downside with 4wd is more complexity. More parts, and with what weight there is needs to be balanced on both ends.

HP as a criteria gives you the ability to do more work faster. Gearing can do exactly the same work but slower.
It's all trade offs.

My preference is a a lightweight 4wd tractor with adjustable wheel width and the ability to add weight. That's my tradeoff. I think that considering weight is fine, but consider the benefits and the cost.

rScotty

 

[Deleted member 371759]

Jeff is invested in weight as the solution to traction. All solutions are trade offs. Weight works to increase traction, but the downside is that extra weight still requires takes energy to move around whether the extra traction is needed or not. Stability? Maybe, but a little extra wheel width gives more of that.

A lightweight tractor with 4wd would have the same traction as a heavier 2wd...but the downside with 4wd is more complexity. More parts, and with what weight there is needs to be balanced on both ends.

HP as a criteria gives you the ability to do more work faster. Gearing can do exactly the same work but slower.
It's all trade offs.

My preference is a a lightweight 4wd tractor with adjustable wheel width and the ability to add weight. That's my tradeoff. I think that considering weight is fine, but consider the benefits and the cost.

rScotty

HP IMO is quite deceiving. What really matters is torque at a usable RPM. Generally peak hp is hit well beyond peak torque in the RPM range. Very few people are using their tractor in high gear red lined to do much of anything.
For example a 2023 3.0 liter twin turbo Porsche 911 produces 443HP which is quite serious Horsepower but only 390ftlb of torque. Max Torgue is made at 5700rpm and max HP at 8000rpm. here is a good calculator to figure torque.

Spicer Horsepower and Torque Calculator

The Spicer Horsepower and Torque Calculator will quickly calculate approximate horsepower or torque, depending on your selections.

spicerparts.com

 

[RjCorazza]

I'll go along with getting the desired frame size, but I don't like to get the highest horsepower engine in a frame size.
If I need that much power I'll go up a frame size.
My preference is for the mid level to lower end horsepower in the frame size. Often that max horsepower is pushing the turbo and intercoolers to the max, I'd just as soon have enough horsepower and be midway in the range.

For me, the decision was similar in the L60 series Kubota. I wanted the larger size and weight that the 4060-6060 offered, but didn't necessarily want the higher HP of the 4760-6060, so I ended up with the L4060. Its primary purpose is snow plowing so weight was important.
My setup comes in at 7100 lbs with cab, loaded rears, and front and rear plows.

 

[jeff9366]

1) Jeff is invested in weight as the solution to traction.

Jeff is not invested in anything. Tractor shoppers frequently become confused trying to understand tractor capability. Bare tractor weight is a "one number" tractor specification easily found in sales brochures and web sites, readily comparable across tractor brands and tractor models, new and used. This "number" should get tractor shoppers into the ballpark. I only recommend bare tractor weight as an objective starting point.

Many with their own preferences justify them one the basis of two or three, sometime more tractor preferences. However, to opine in my playground on an apples-to apples basis, others must stick to one (1) criterion too.

I have owned three tractors. The first a 2-WD,1,900 pound, Deere 750 compact category "learner" without a Loader. The second a 4-WD Kubota B3300SU tractor-loader package (2,200 pounds +/-). The third, a 4-WD 3,700 pound Kubota L3560. Had I early read a thread philosophizing on tractor weight it would have stimulated tractor weight research and I would have omitted purchase of tractor #2, which was hardly any heavier that the Deere 750, which proved too light for my applications. I purchased tractor #2 seduced by the allure of increased horsepower.

 

[rScotty]

HP IMO is quite deceiving. What really matters is torque at a usable RPM. Generally peak hp is hit well beyond peak torque in the RPM range. Very few people are using their tractor in high gear red lined to do much of anything.
snip.

Yes, Torque is the answer, HP only gives you speed.

Most tractors are the roughly the same in that their torque is flat from just past idle to just below full HP.
On my Kubota, high torque starts at about 1000 RPM and doesn't change much. At 1100 RPM it is near max and stays above that same number until over 2200 RPM. Doubling the RPM does doubles the HP, but that only increases the speed the tractor can work, it doesn't change what it can do at all. At high RPM, wear goes up disproportionately, as do fuel & all maintenance costs.

My guess is that most of us didn't buy a tractor to go to the races. We enjoy the work, and chosing to take a little longer to do the same job for less wear and tear is the choice we tend to make.

rScotty

 

[workinonit]

HP and weight do not directly correlate. Most brands sell 2-4 HP options on the exact same frame. HP goes up, weight stays the same. Some brands are lighter across all HP than others. Kubota, for example, JD for another. Probably due to their superior materials and workmanship. However, Jeff is not wrong that weight improves traction and stability.

For me, it is a both-and, not an either-or situation. Need good HP and decent weight to apply that HP.

Pretty much exactly what I said. Both HP and weight are needed and 4WD if you are pulling plows.

 

[rScotty]

Pretty much exactly what I said. Both HP and weight are needed and 4WD if you are pulling plows.

Pretty much. Torque tells you IF you can pull it; HP tells you how fast you can pull it.