HST or 12 speed SHUTTLE SHIFT

[sandman2234]

So many choices, yet can only pick 1 tractor!

WHY? and please don't tell my Bride! Is there a reason you can't pick more than one tractor?
David from jax

 

[sandman2234]

I am blessed to own a shuttle shift and while I have never owned a HST, I am glad I don't have to listen to the whine of a hydraulic pump all the time!
When one breaks down, which is going to be easier to fix? Cheaper to fix? Cheaper to maintain? Hydraulic fluid isn't getting any cheaper and having to change it "how often?" has to add to the ownership cost.
David from jax

 

[R Barger]

I am blessed to own a shuttle shift and while I have never owned a HST, I am glad I don't have to listen to the whine of a hydraulic pump all the time!
When one breaks down, which is going to be easier to fix? Cheaper to fix? Cheaper to maintain? Hydraulic fluid isn't getting any cheaper and having to change it "how often?" has to add to the ownership cost.
David from jax

Thanks for all of the responses. Loader work only accounts for about 10% of the work this tractor will do. My most interest is crawling around on these hills with a bush hog and durability since this most likely only new and last tractor I'll buy. At 72 years old and I will only use this tractor about 100 hrs a year. I still think about how enjoyable it is crawling around on these hills with the Kubota RTV X900. It took me awhile to get past the REGEN but since I always have run my tractors at 2000 RPMs that may not be an issue. That new YM Yanmar is interesting but I understand it is a bit pricey. Wanting 35 to 40 HP. I'll be taking all these suggestions seriously. Also I will still have another tractor for a backup and other uses.

 

[Gjamtrac]

Thanks for all of the responses. Loader work only accounts for about 10% of the work this tractor will do. My most interest is crawling around on these hills with a bush hog and durability since this most likely only new and last tractor I'll buy. At 72 years old and I will only use this tractor about 100 hrs a year. I still think about how enjoyable it is crawling around on these hills with the Kubota RTV X900. It took me awhile to get past the REGEN but since I always have run my tractors at 2000 RPMs that may not be an issue. That new YM Yanmar is interesting but I understand it is a bit pricey. Wanting 35 to 40 HP. I'll be taking all these suggestions seriously. Also I will still have another tractor for a backup and other uses.

What about a comparison of efficiency of HST vs PS (PowerShift)? I have always heard that HST is only about 60% to 70% efficient. To get the same amount of power to the ground or to the PTO, would you need a 30% more powerful engine in a HST tractor compared to a PS?

 

[ponytug]

What about a comparison of efficiency of HST vs PS (PowerShift)? I have always heard that HST is only about 60% to 70% efficient. To get the same amount of power to the ground or to the PTO, would you need a 30% more powerful engine in a HST tractor compared to a PS?

I think that the devil is in the details.

The actual HST efficiency depends heavily on how the HST is set up, and whether the pump or motor or both are variable volume pumps, and the actual design. That said hydraulic pump/motor efficiency is in the 80-90% range, but that means overall the efficiency would be in the range of 64-81%.

What often gets lost in the efficiency discussion is whether tractor engine is at its maximum efficiency point, when the tractor is at the desired ground speed. Then there is the time=money for the operator: will the operator get more accomplished in a day with an HST or PS, for that given task.

It's not a simple call in my book, and I think a great deal depends on the work being asked of the tractor.

All the best,

Peter

 

[R Barger]

What about a comparison of efficiency of HST vs PS (PowerShift)? I have always heard that HST is only about 60% to 70% efficient. To get the same amount of power to the ground or to the PTO, would you need a 30% more powerful engine in a HST tractor compared to a PS?

Good point I don't want a 50HP tractor to get 35HP in power. The size of the 50 to 55 HP tractors is to large for my needs.

 

[Cycledude]

For running your Bush Hog for 100 hours per year and being 72 years old you will never wear out a good HST.
My newest tractor is HST and I love it.
I’m sure some of the other choices are also very nice and you probably wouldn’t be able to wear those out either.

 

[airbiscuit]

Someday all CUTs will have transmissions this good (i-HMT). The power of a shuttle, the convenience of a hydro. Plus, it can be accessed without splitting the tractor!

 

[hayden]

I think that the devil is in the details.

The actual HST efficiency depends heavily on how the HST is set up, and whether the pump or motor or both are variable volume pumps, and the actual design. That said hydraulic pump/motor efficiency is in the 80-90% range, but that means overall the efficiency would be in the range of 64-81%.

What often gets lost in the efficiency discussion is whether tractor engine is at its maximum efficiency point, when the tractor is at the desired ground speed. Then there is the time=money for the operator: will the operator get more accomplished in a day with an HST or PS, for that given task.

It's not a simple call in my book, and I think a great deal depends on the work being asked of the tractor.

All the best,

Peter

I agree with all this, but think it only matters if your needs include max pulling power for ground engaging implements, and I think that only occurs in the large row crop tractor realm. It's fundamentally why those large tractors are power shift or IVT. If you are pulling a plow through the ground all day at max pulling power, then it matters. Otherwise I think the control and maneuverability of an HST greatly outweighs the small loss of efficiency.

 

[hayden]

For running your Bush Hog for 100 hours per year and being 72 years old you will never wear out a good HST.
My newest tractor is HST and I love it.
I’m sure some of the other choices are also very nice and you probably wouldn’t be able to wear those out either.

Agreed. In my experience HST reliability is the last thing you need to worry about.