Do Hydrostatic Trans Eat HP?

[RidgeHiker]

Is there a significant loss of power with a hydrostatic?

 

[dex3361]

The Hst loses a bit more HP but it is well worth it. For example the L4400HST Kubota in Gear has 37.5 PTO HP and the same tractor with an HST trans has 35 HP.

 

[radman1]

I would estimate the loss in drawbar hp to be about 10-15% compared to geared. Most of us don't use CUTs for heavy pulling and therefore in the real world, it is not that apparent. Many CUTs have more hp than traction, especially in the larger CUTs. My JD 4520 will run out of traction before hp in most tasks.

 

[wolc123]

It does eat some HP but not necessarily does it eat more fuel. For some tasks, most notably lawn-mowing, where the ability to continuously vary ground speed is a huge advantage when mowing around trees, etc, the hydro will normaly get the job done in less time with less fuel. For other lobs, like discing a large fuel, the hydro is at a disadvantage and will eat more fuel, hp and not save any time.

 

[TripleR]

I am sure it does, but as mentioned both our 5030 HSTC and M8540 HDC run out of traction way before they run out of power.

I liked the L4240, but was concerned about the power loss to the AC and cab weight so I bought the 50 HP 5030, for the convenience of the HST, I am more than willing to adjust.

 

[crazyal]

Is there a specific task(s) you have in mind? You do take a little HP hit but it's not as easy to point to a published number and say "that's how much". In the real world you're usually matching a speed with the amount of HP needed. For example, if you're running a brush hog you may need to go slightly slower with the HST. If the speed you want to go at is in between two gears you really haven't lost any HP because the gearing limits how much HP you can use.

 

[RidgeHiker]

Is there a specific task(s) you have in mind? You do take a little HP hit but it's not as easy to point to a published number and say "that's how much". In the real world you're usually matching a speed with the amount of HP needed. For example, if you're running a brush hog you may need to go slightly slower with the HST. If the speed you want to go at is in between two gears you really haven't lost any HP because the gearing limits how much HP you can use.

We live in the mountains in California, at times get a lot of snow, and our main purpose is snow removal. We will also use if for scraping our driveways, moving substantial amounts of dirt, etc.

 

[texasjohn]

My opinion, hp is a non issue as regards gear vs HST.
The reasons are many, quite a few mentioned below.
IMHO, the advantages of HST of speed control, safety, etc are key decision factors. HP is important, but once you are within the right couple of hp for your needs, hp is a non issue. Make your decision on other factors...but for goodness sakes drive an HST under true work conditions before making your decision.

 

[crazyal]

We live in the mountains in California, at times get a lot of snow, and our main purpose is snow removal. We will also use if for scraping our driveways, moving substantial amounts of dirt, etc.

HST would be idea for what your talking about. For snow removal HST allows the use of a snow blower (front or rear) while being able to change speeds without adjusting the RPMs. For dirt work with a loader HST also works well because you can change directions by simply pressing the pedal, no change of throttle, no clutch, just push the pedal in a different direction.

 

[Soundguy]

i agree.. it consumes a lil more hp than straight gear.. but any pto application the gear was suitable for the hst should work with as well. if you are that close that 1-3 hp makes a go / no go difference in an application.. IMHO.. you are buying too small anyway.

some application may simply be more efficient with gear.. but both trans will do the same work that the chassie is up for.

IE.. if I mowed or plowed all day.. and had no obstacles.. i think I'd go gear.

if I did loader work or ran around obstacles all day.. perhaps hst.. etc.

soundguy