Hydrostatic (HST) Transmission Longevity?

[cowboydoc]

I agree with your dealer. On this board I doubt you'll find many people that don't like the hydro. Most people here have small acreages and put at most a hundred hours on their tractors a year and don't push the tractor to their limits. If you are in this category I don't think you'll have much problem with the hydro.

I know several equipment mfg. that always ask me if I have a hydro or a gear tractor when sizing implements. Most of them say that the hydro will not do the same work with an implement that a gear tractor will.

I had the chance to make a very good deal on a new 4720 but the only way to get it is with a hydro so I passed.

 

[Darren]

"Most of them say that the hydro will not do the same work with an implement that a gear tractor will. "

Doc, I think we can agree that with a fluid drive system you'll have power losses that don't exist with a gear box. It seems logical to me that can translate into a difference in attachments. Whether someone with a CUT will notice that is something else.

If we were talking versatility I think the hydro wins hands down due to it's adaptability to control and the ability to match output to load. John Deere's info on the loader via the link in my previous post nails that.

The issue here is longevity. With all the posts at TBN, I haven't read about problems. It might be an interesting exercise to google for examples of problems. I doubt much would be found.

In a nutshell, I don't think longevity is a useful criteria in making a hydro vs. gear purchase decision by the average buyer who frequents TBN.

 

[755inNY]

Cowboydoc,

<font color="blue"> I agree with your dealer. </font>
What are you agreeing with? That you have never seen an HST last over 1500 hours?

<font color="blue"> I know several equipment mfg. that always ask me if I have a hydro or a gear tractor when sizing implements. Most of them say that the hydro will not do the same work with an implement that a gear tractor will.
</font> While that's a valid point it does not address the question of longevity. There is more HP lost in power transmission in a HST vs. a GST so a GST might be thought of as being able to do more work but that does not mean the HST has less longevity when doing the work it was design to do. And that includes working to its limits in loader work, tilling, boxblading etc. The HST is not the right choice for plowing ground.

Jeff

 

[Ole_Hickory]

Darren,
I am down here in Wood County WVa and I have A JD 4400 hydro and I have about 1200 hours on the tractor and I have taken lots of large timber out of some deep hollows. With this JD 4400 hydro I feel confident I would have smoked a clutch by now if it had been a geared tractor.Some times I have to yank a log to get it started skidding and I have abused the heck out of this tractor and the hydro has held up extremely well. I have had the tractor standing on its back wheels trying to get a log up a 20% grade. I can go forward and backwards under load as quick as the hydro will allow me. I have dragged logs all day up hills under constant load and the hydro has never once hinted of failing.
I have owned and operated several geared tractors and I can assure you this I would never have anything but a hydro.
Why would John Deere make a JD 4720 and not offer it in anything but a hydro ?
Versatility....no question a hydro is more versatile, anytime you can operate a machine and keep both hands on the steering wheel and switch from forward to reverse as fast and often as you want,not to mention the infinite speed control the machine is more versatile.

My biggest gripe with my JD 4400 has been the wheelbolts coming loose and the differental lock not holding up,but I am using the tractor under extreme conditions,believe me I have tested the tractor and found the week spots,but the average person would not push one like I have either.

Just my opinion and experience.

 

[OrangeGuy]

I spoke to a dealer today who does not sell HST tractors

This statement says it all and is the basis for the dealers negative perceptions regarding hydrostatic transmissions. I have a 30 year old Allis Chalmers 620 tractor with a Sunstrand hydrostatic transmission. It works as well today as it did 30 years ago.

In addition, the Bobcat Company started selling hydrostatic transmissions in 1970. Before that they sold "mechanical" transmissions. With the introduction of the hydro, sales took off. About a year and a half ago Bobcat passed the 500,000 mark in units sold. I would estimate more than 80% are hydro.

The hydrostatic transmission is a time tested and proven technology. In most applications where it is used, it has increased productivity, safety, reliability and customer satisfaction.

If the dealer you visited sold tractors with hydrostatic transmissions, I am confident that he would have provided a different answer.

OrangeGuy

 

[OrangeGuy]

Sorry about the all bold message. My intention was to only bold the first sentence.

OrangeGuy

 

[Darren]

Hickory,

I originally bought my L3710 for the missus. She was mowing with a Gravely rider and decided to change gears going up hill. She got confused and the next thing it was in neutral going down hill backwards. She jumped off and other than a few bruises and being really angry, was OK. A fence kept the Gravely from going over a fifty foot drop.

With the hydro I figured she didn't need to think about braking as much. Other than that, I didn't consider any other aspect of the hydro. I was used to geared transmissions. Anymore I use that L3710 for just about anything. A recent exception was a friend of one of the kids who tried to pull a fair-sized double axle trailer across the creek and up a rocky grade with a dually one ton. I don't know why he even tried.

I used the Ford to drag the trailer out of the creek. To be fair the tongue weight on the trailer was probably too much for the L3710 and I didn't want to take the sickle bar off anyway. Lucky for the kid I fixed the flat on the Ford the day before. That's what the Ford does most these days. Tows stuff out of the creek or up the road to the house. I did use the L3710 once to winch the Ford hooked up to a triple axle flat bed loaded with a truck up the same grade.

The hydro L3710 does almost everything else with the other exception of backblading. It's a sweet tractor and just the right size to maneuver in the small fields. In the larger fields I can easily adjust speed when I need to slow in heavier grass while cutting. Same with baling. If the windrow got a bit chunky, just slow down. After the L3710, I wouldn't buy anything but a hydro for what I normally do.

 

[Ole_Hickory]

Darren,
A hydro is very user friendly for the not so experienced tractor operators. I am glad your "missus" was able to get off of the Gravely and not suffer anymore injuries than she did. The hills and hollows are a lot steeper in WVa where your are located than here in Wood County though they are plenty steep here at my place.

 

[Gary_in_Indiana]

OrangeGuy,

You can view your own message and hit the 'edit' button to correct things like that within 12 hours of posting if you'd like. /forums/images/graemlins/smile.gif

Edited to make a correction changing the original "24 hours" to the correct "12 hours" after a PM alerted me to my error. /forums/images/graemlins/blush.gif See? This editing thing really does work. /forums/images/graemlins/grin.gif

 

[JimR]

Tell that dealer he is [censored]. My 1995 Cub Cadet 7275 has 2300 hours on it now. It has a HST tranny and works fine. This machine has not been babied from what I can see. I have also seen quite a few others with over 1500 hours with HST's that didn't look like they had ever been apart. I bought mine used and have been pushing it to uproot small trees, leveling the ground, pulling roots, moving stones and clearing out a new section of woods. I also have been using my 6 foot box blade and 6 foot MMM on it without any problems with the HST. I have a problem with a standard shift. My left knee is not to good thanks to plowing driveways with a F250 standard shift and using the old Ford 8N I had years ago. The HST was the only way for me to go when I bought the Cub.