My Tractor Forum banner
  • Are you passionate about Tractors? Would you like to write about topics that interest you and get paid for it? Read all about it here!
1 - 8 of 8 Posts

·
Registered
Joined
·
189 Posts
Discussion Starter · #1 ·
I am new to garden tractors and I may purchase a Cub Cadet 1512 which has hydrostatic drive. I understand that the wheels are driven by hydraulic motors which provide adjustable speed and torque and also function as a brake, but I could not find an answer to my question. If one drive wheel is off the ground or slipping freely, does the other wheel get any torque? I looked at a Simplicity Powermax 4040 and the guy said that it did not have a differential lock, so I assume it had a mechanical drive. Maybe this is a dumb question, but I'd like to know. :thanku:
 

·
Deceased Member
Joined
·
2,027 Posts
... Maybe this is a dumb question, but I'd like to know. :thanku:
The only "dumb question" is one that you don't ask.

That would be a function of the rear end/differential, and not the transmission, so it would depend on the tractor.

Take Bolens for example. All of the Hydrostatic Tube Frames have a "Controlled Differential" that will put power to both sides at all times. The Large Frames do not, and if one wheel slips/spins, the other wheel will not turn.

ETA:
Your best bet would be to pop down to the Cub Cadet Forum and ask those guys. I'm sure that they would be glad to help you out
 

·
Super Moderator
Joined
·
23,312 Posts
:MTF_wel2: , PStechPaul!!

Hydrostatic drives usually consist of 1 pump and 1 motor, plus periferals to do the job. The motor powers the rear end which includes a differential, similar to a car. The same problems that plague a car also plague GTs when one wheel is in the air.

Limited slip differentials are available for some GT rear ends, as are differential locking devices. The diff locks will cause power to be distributed to both rear wheels, even if one is in the air.

The hydro is just a replacement for the multi speed gearbox transmission part of a transaxle. Many hydro tractors have the same final drive/differential components as similar tractors with manual gear boxes.

Infinite speed control and rapid direction changes are the hallmark of hydros over manual transmissions and both deliver power to the rear axle. Delivering power to the ground is the domain of the axles.

EDIT: I see I was slow typing.
 

·
Premium Member
Joined
·
3,479 Posts
The 4040 has a hydro unit in front of a 3 speed gearbox that is in front of the differential
so you have hydro drive and 3 ranges.It doesn't have locking differential which has nothing to do with whether its hydro drive or not as the locking mechanism is in the rear on tractors that do have it.The 4040 does though have independent rear brakes which when one wheel spins the brake for that wheel can be lightly applied to make the other wheel start to pull.Heavy duty tractors that are capable of doing alot of work that most garden tractors aren't capable of doing.
 

·
Registered
Joined
·
189 Posts
Discussion Starter · #5 ·
OK, that helps a lot. I thought that perhaps there was a separate hydraulic motor for each wheel. This is important to me because I need to negotiate a steep access road that has deep ruts, and it is possible that the tractor could get hung up on three wheels. My old Simplicity Broadmoor has a rotating connection between the front and rear, so the frame essentially twists to keep all four wheels on the ground. I noticed this when I drove my tractor down the hill and I hit a deep rut with the front wheel, and the entire front, including the dash and steering wheel, twisted, almost pinning me in the seat. I can see this as a safety issue as well, since it could cause rollover.

Thanks!
 

·
Tech Nerd Tractor Convert
Joined
·
1,388 Posts
Or you can get an i-Series, which has 2 hydros (one per wheel) and no differential. Each will maintain traction independent of the other.

The i-Series is also very stable on hills. Low center of gravity and wide stance.

Plus it turns on a dime which is cool, but still handles attachments.

However a full GT it is not. In toughness, it's somewhere between a GT and an LT. The hydros are light duty and the frame is stamped steel, although beefier than a tin can. So if you're planning on ground-engaging work it may not be the tractor for you.
 

·
Registered
Joined
·
662 Posts
Sounds like what you really need is a tractor with a back blade, loader, etc. to do some work on that rutted access road.

BTW, differential locks and limited slip devices can cause problems, especially on wet or uneven ground. They tend to push a machine sideways in low traction conditions and make turning difficult because, without a differential, one or both wheels must slip to compensate for the different curve radius of the inside vs. outside wheel on a turn. They are mostly useful for straight ahead pulling - like ploughing
 

·
Registered
Joined
·
189 Posts
Discussion Starter · #8 ·
I might just hire somebody to spread stone on the access road. I was able to get up and down without too much trouble, at least without towing the trailer. It would be good if I could lock the differential just when pulling straight up the steep sections of road, but I think it will be OK.
 
1 - 8 of 8 Posts
Top