Hydro vs Geared

Bird · Apr 24, 2003

Murph, I think a lot of people have learned the same lesson over the years about the automatic vs. manual cars and pickups. For many years, the City of Dallas would not buy an automatic transmission vehicle; too expensive to repair. Then someone finally wised up to the fact that, yes, they're more expensive when you have to repair them, but you don't have to repair them nearly as often. They even figured out how to add a hydraulic pump run by a belt off the engine to run the packers on the garbage trucks with automatic transmissions instead of using manual transmissions with a PTO.

I have some doubts that the hydro tractors have been around long enough yet to determine for sure whether they'll cost less in the long run (20 to 50 years), but if I had to place a bet, I'm bettin' the hydro will be cheaper in the long run.

MODiesel · Apr 24, 2003

Bird:

Combines have been using Hydro for years. I don't even recall when they became popular on combines, but I think that's a fair application considering the weight of a loaded combine.

Honestly, hydro is not that complicated. I would that getting to the hydro components might be the biggest part of any repairs.

Best Regards,
Jay

Soundguy · Apr 24, 2003

( to back up the pto briefly disengages until you let the clutch back out. )

Oh.. I gotcha. I'm spoiled by the 2 stage clutch in my 1920... just clutch to first peg, and can shift, stop, etc with pto still going..

Soundguy

Soundguy · Apr 24, 2003

( have been led to believe that a hydro transmission, due to the very nature of its design , is destined to "wear" out. Now, hold on, I'm aware of the fact that the gears in any transmission will wear out in the really )

Keep in mind that a clutch in a gear tractor is a 'designed' to wear item as well.

( Was this inflammatory rhetoric designed to steer me away from hydros? Is this long time a *really* long time, like 20-30 years or normal use? )

I think the issue is that if you look at the collective tractor experience in the long term like you mention.. gear tractors have been built since way back... Many of us here are still working 30's 40's and 50's era tractors as our regular farm tractor.... We know about what to expect out of a gear tranny.. and about how long the life span is...

Problem is we can't speculate as much on hydro's on farm tractors as there is less colective long term experience about them.. there weren't any hydro tranny ford 9n's in 1939 to compare to the gear model 9n in 1939 for us to do the apples to apples comparison with... for loengevity purposes.

I don't think anyone is trying to steer you any particular way.. each of us is giveing you our experiences on our particular equipment weve used.. and what we observed and liked / didn't like. Etc.

In the end, the choice will be between you and your wallet, and will be based on what you want to do with your tractor. Bottom line... both are good units, and it will be hard to lose either way... one is just better suited for a specific purpose than the other... but both will work..

Good luck!

Soundguy

Soundguy · Apr 24, 2003

( But thinking about self-wrenching on a hydro 15 or 20 years from now scares the willies out of me )

I see your point.. but then.. for instance.. I own a 52 8n tractor.. earlier this year I had to tear down the steering box to replace a broke shaft.. didn't know whether I was up to it... deffinately wouldn't have considered it 2 years ago, or before i was reading here. I imagine in 20 or 30 years if you still have that tractor and the hydro goes out in it, it will be similar to us finding parts for our antique tractors, and just fixing it.. as by that time.. that will be 'old technology'... we might even be sitting around talking like " Yep.. I remember when all the trannies were like that back in the early 00's.. etc.. etc..
In 20 or 30 years.. you'll pick up more tractor 'wrenchin' skills...

Soundguy

thcri · Apr 24, 2003

You know when I come to think about it, back when I was 10 years old I use to help me neighbor some, he delivered International Harvestor tractors for a living. I always got to drive the Cub Cadets. They had a Hydro-static model back then. That would be in the mid 60's. Hmm maybe that is where I got my desire to have a tractor.

murph

sendero · Apr 24, 2003

( Keep in mind that a clutch in a gear tractor is a 'designed' to wear item as well. )

Yes, but anybody can replace a clutch - and a clutch plate costs little to make or buy /forums/images/graemlins/grin.gif

My question was more about exactly *how* a hydro works. It is not anything like an automatic transmission according to what I've been told. The beauty of an auto trans is not in the trans so much as the torque converter, which I've been told does not exist in a hydro trans. I agree that an auto trans is overall less a reliability issue in cars, but I'm not sure the comparison is very analogous.

This is largely academic for me, as I'm stretching myself to buy a new tractor and a hydro is simply out of reach price wise. But I was interested in exactly *how* they work. I know they use hydraulics but I don't know much more...

Bird · Apr 24, 2003

Sendro, when I bought my last Kubota, I also ordered the Workshop Manual and the Illustrated Parts List, which I'd recommend anyone do. You really need both of them together. I don't know that I could find it, but there have been some discussions in the past on the forum, including some drawings of the working of the hydro and I think it's less complicated than a car automatic, but can't say for sure because I've never actually had to tear either one down.

DK35vince · Apr 24, 2003

( . My neighbor has a geared tractor and whenever he has to reverse he has to cut out his PTO, shift, reverse, shift again to forward, then go again.

With my hydro, I just stomp on the "back" pedal and I'm going backwards, PTO still running strong, and then hit the "forward" pedal and I'm going again. )

This is true about gear models without live PTO.
My DK 35 has shuttle shift and Independant PTO.
To reverse I flip a lever on the steering column with my finger tips, to go forward I flip it to forward with my finger tips. PTO (still going strong) does not shut off .

MODiesel · Apr 25, 2003

Sendero:

I've found the following link to have the most comprehensible explanation of how Hydro works:

Click Here

Best Regards,
Jay

timb · Apr 25, 2003

Ahh but that old Ford like most tractors of it's era were designed to be maintained by a farmer. Not sure that part's been kept in mind on the newer stuff. We've had our '53 NAA apart a few times, including a full engine rebuild a couple of years back. They're straightforward to work on for the most part. Next up is to tune up the hydraulics - there's a few leaks and sticking bits on the hitch hydraulics. None of it seems impossible to tackle given a good manual and some patience.

But looking at things like hydros, fuel injection pumps/injectors, the electronic bits (especially on the hydro JD's) and my confidence in being able to diagnose/cure down the road issues slips a bit. /forums/images/graemlins/grin.gif

Hope you're right - someday we'll look back and barely remember what the fuss was about.

sendero · Apr 25, 2003

Thanks Diesel_Jay. That is indeed a good explanation, and based on it I'm doubtful about the idea that hydros are inherently not long-lived.

Surely, as far as wear goes, a pump typically *does* wear out over time. But so does a synchro. The issue is how much time. Synchros will last a long time unless abused. I can easily imagine a hydraulic pump lasting a long time, after all it is literally immersed in lubricant /forums/images/graemlins/smile.gif

The only other issue would be seals - but I think materials have improved a lot over time. So my opinion has changed, I don't really think there is any reason to think that hydros will not hold up for the long haul.

Now if I could just afford one /forums/images/graemlins/crazy.gif

Bird · Apr 25, 2003

Just think of the cost spread out over 20-30 years and it doesn't seem like nearly as much. /forums/images/graemlins/laugh.gif

Anonymous Poster · Apr 25, 2003

I just read the description in Jay's link, and it agrees with what I understood about how hydros work. There are still some gears, or at least splines, involved, however, because the power from the engine has to be coupled to the hydraulic pump and the hydraulic motor has to be coupled to the axles.

My son-in-law bought a used hydrostatic Craftsman garden tractor (22 HP gas, 50" cut) and the transmission "quit". He had run up against a stump buried in some grass, and didn't back off. Now, these garden tractor pumps, motors, splines and such as not as robust as a tractor, but the short story is that it cost over $700 in parts and about 4 hours of labor to rebuild it (total bill $963 with tax). The pump was replaced, and the shop saved the broken spline units because I was curious. Some of the stuff just shattered. It may just be my paranoia, but the unit doesn't seem to work as well as it did, so there may be some tolerances and/or adjustments that the mechanic didn't perform very well (sort of like using a dial indicator and shims to set end play when rebuilding an automotive automatic).

With all that said, I'm assured by the service manager at my dealer (yes, I talked to him before I bought my tractor) that the hydros in a compact tractor are very robust and overbuilt to avoid the sort of theing we experienced in the garden tractor. So, I bought one for the convenience, ease of use and versatility - but I have no confidence that it will be working as well 50 years from, like the 8N I almost bought until I got over my nostalgia. On the other hand, 50 years from now I'd be 112 (and I don't want to be that old), so it will be someone else's problem.

MossRoad · Apr 25, 2003

Here's a link to one of my favorite discussions on Gear VS Hydro. Good reading.

And here's a real good one with links to pictures, diagrams and other cool explainations. /forums/images/graemlins/smile.gif

froggy · Apr 25, 2003

Thanks for the links. Even with loader work, I prefer gear over hydro, but that is just my personal quirk.

BWS · Apr 25, 2003

i would buy what you drive.auto in truck get it in a tractor after all is it not the same theory??i would like to think my dodge 2500hd diesel would be the last truck i would need to buy.jmho bws

prosperity · Apr 25, 2003

Just to add a little to this - by the way I'm hydro all the way for small tractor applications.
Like any hydraulic system, dirt is its worst enemy. If you're starting with a brand new tractor, pay very close attention to cleanliness when changing fluid/filter. In a perfect world where you would never have to open the system at all, wear would be at a total minimum. But, we have to change the fluid/filters every so often. The first change is to get rid of any metal shavings in the system from manufacture. Then, fluid changes need to be made since even hydraulic fluid will break down after a period of time after being under pressure and heat.
So....the reason for this rant.....If you change your fluid/filters under extremely clean conditions, you're limiting any dirt getting into the system. Any kind of foreign matter getting into the system will prematurely wear the internal parts. I'm picturing in my mind changing those fluids/filters in a hospital operating room or computer chip manufacturing operation.

Keep it clean and keep it cool!

MAW · Apr 26, 2003

I would like to thank everyone for their experienced advice. I can see that I am going to become a "pest" to you as I go through my tractor owning experience, please just have patience with me /forums/images/graemlins/smile.gif. I can see that this is not a cut and dry issue and I am going to just have to bite the bullet and make a decsion. I am still leaning toward the geared since most of the work I will be doing is mowing/ground work, and very little loader work. Thanks again, I am very glad my wife found you!!!!! /forums/images/graemlins/laugh.gif

ns_in_tex · Apr 27, 2003

I tried not to get involved in this discussion since it started, but you finally got to me.
I own 3 tractors, 2 geared & 1 hydro. I agree if you are going to the field to pull a breaking plow or similar, all day, the geared tractor is the way to go. IMO if you are going to do utility work, where it is desireable to change speeds, directions, ETC, I could never be happy again without a hydro.
I know some say they can do anything with a gear that I can do with a hydro, but I do not agree with that statement. I think in many utility operations, you can do twice as much work, with 1/2 the effort, with a good hydro.