What You Need To Know – Craftsman Transmission Types Updated: March 2010

Craftsman uses four basic types of transmissions in their 2010 Lawn, Yard, Garden and Professional Series Riding Tractors.   Of the five types the new Infinitak and Automatic transmissions are going to positively change the way we mow lawns.

The fives types are Infinitrak,  gear, automatic, and hydrostatic.  I’ll spend a few minutes going through each type so you have a better idea of the best type for you.

I’m not going to show you pictures of the different types of transmissions.  What they look like is not important to you, how to use them is.  If you would like to see pictures of the actual transmissions use the references listed at the end of this article.

Infinitrak

Get used to the term “toroidal transmission”  There are a group of manufactures rapidly developing this type of trans for the small engine market and you will see many varitations of it available in the next few years.  It is a giant step forward for the riding lawn tractor industry.  Sears is using  a Twin Toroidal Transmission (TTT) made by Infinitrak in the new Revolution Yard Tractor.

The TTT is a proven design and provides many benefits for mower performance and driver experience over the current gear and hydro transmissions including:

• Efficient, quiet operation and drivability
• Precise speed control – for ease of maneuvering around obstacles and lawn borders
• Better control of power delivery to the wheels – reducing wheel slip and turf damage
• No gear changing
• Seamless forward to reverse
• True ‘zero-turn’ capability
• GEARED Neutral

From the Torotrak website: “Advantages of the IVT to ride-on mowers.  The full-toroidal Infinitely Variable Transmission (IVT) provides a refined, smooth drive with no gear changes. Its precise control and ability to shuttle seamlessly from forwards to reverse allows ease of manoeuvrability around obstacles. The consistent and easily controllable delivery of power to the wheels reduced the tendency to wheel spin and leads to a consequent reduction in ground damage. IVT is also very quiet in operation and therefore offers reduced noise pollution.”

Gear:

The six speed manual gear drive is the basic transmission available on Sears Tractors.  To drive the tractor you must push in on the clutch, shift the transmission to the gear you want to use, release the clutch, and hang on.  This is a dependable  transmission that will give you years of service.

There are different sizes for the different models for lawn, yard, and garden tractors are are sized to be able to pull non-ground engaging attachments with your lawn or yard tractor.  The manual transmission in the garden tractor is heavier and sized to be able to pull all the attachments Sears offers including ground engaging items.

Automatic:

The automatic transmission on the LT2000 Model 28904 uses a belt drive system similar to the type used in snowmobiles to vary the ground speed.  This drive is fast and responsive.  To operate the transmission all you have to do is move the fender mounted lever forward to go forward and pull it back for reverse.

The automatic is designed to pull most non-ground engaging attachments Sears offers.  I would suggest though you don’t pull more than 300 lbs of dirt, etc. as heavier loads may wear the drive belt prematurely.   You can see a diagram of this transmission by going to Sears parts and searching for 917.289080

Hydrostatic:

Sears uses three styles of hydrostatic transmissions on their tractors.  A single hydrostatic trans-axle is used on the hydro lawn and yard tractors.   A  heavy-duty unit is used on the Excellerator Garden Tractor.   A dual system the ZTS 6000 series zero turn yard tractors.   The transmissions are sized to the tractor and motor and ONLY the Excellerator is sized to be able to pull all of the ground engaging attachments Sears offers.

Hydrostatic – How to use:

Craftsman Lawn, Yard, Garden, Revolution Tractors.  The pedal on the left side of the tractor is the parking brake.  You do not need to depress that pedal to shift the tractor.   The forward and reverse is controlled by either a lever on the right fender or two pedals on the right side floorboard.  To go forward push the fender lever forward or press on the large pedal on the floor board.  To stop the tractor pull the lever back to the middle position or lift your foot off the pedal.  To back the tractor up pull the fender lever to the rear or press the small pedal on the floorboard.

On the fender mounted control you HAVE to move the lever to the middle to stop your tractor.  It will not go to neutral by itself like the foot controls.

ZTS 6000.  On this mower a large lever on each side of the seat controls that side transmission.  To go forward push on BOTH levers.  To stop, pull them back.  (The easiest way to explain how to drive a two-lever zero turn mower is to  use a shopping cart as an example.  With the mower turned off sit on the seat and put your hands on the two large levers in front of you.  Close you eyes and pretend you are gripping a shopping cart.   What do you do to move a shopping cart forward? Right, you push on the handle.   To back up? Right, you pull back on the handle.  To go left?  To go right?  Correct, you PUSH the handle in the direction you want to turn the cart.  Two lever zero turns work the same way.  Instead of one bar like a shopping  cart, the bar is split in two and you move each side to make it move.)  This type of transmission takes practice to keep the tires from digging into your lawn.

Reference:

Infinitrak Transmission.

NuVinci Transmission. Sears is not using this transmission yet, but it has some very good explanations of how a toroidal transmission works.

6 speed transmission diagrams

Automatic Transmission Diagram

Related posts:

1. What You Need To Know – Lawn Tractor Types
2. My New Craftsman Lawn Tractor, Yard Tractor, Garden Tractor, or Professional Won’t Run!