Powdered Metallurgy Tuff Torq

[bc.gold 3,403]

Scroll down to gears, powdered metal, upgrading to steel optional $$$ - ???. My Deere LA 175 has a Tuff Torq, now I know why the rich guys trade them in for a new mower every couple of years. Consumer grade trans-axles do not offer the upgrade.

K574

Manufacturer ID: K574

If your application needs a transaxle that can support good performance and 4WD technology, or calls for secondary hydraulic support, the K574 may be just what you’re looking for.  This powerful unit has many different configurations that have been developed to handle the demands of many different kinds of riding mowers and larger lawn tractors.  The K574 is truly a “Swiss Army Knife” of transaxles.  It’s substantial engineering, and wide variety of support solutions, has made this powerful product one of the first solutions to many OEM’s complicated and innovative new product applications.

 

Specifications

Specification	Value	Units
Application	4WD Tractors and Mowers Ride-on Mowers Articulating Mowers 4WD industrial sweepers Self-Propelled industrial machines
Reduction Ratio	31.68:1 28.04:1 21.53:1
Axle Torque (Rated)	31.68:1 = 255 (188) 28.04:1 = 235.4 (174) 21.53:1 = 180.7 (133)	Nm (ft-lb)
Max. Tire Diameter	31.68:1 = 559 (22) 28.04:1 = 508 (20) 21.53:1 = 457 (18)	mm (in)
Brake Capacity	31.68:1 = 372 (275) 28.04:1 = 330 (243) 21.53:1 = 253 (187)	Nm (ft-lb) *@350 N (79 lb) Brake arm force
Displacement (Pump/Motor)	7/10	cc/rev
Max. Input Speed	3,400	rpm
Axle Shaft Size	19.05 (0.75)	mm (in)
Weight (dry)	12.5 (27.6)	kg (lb)
Brake Type	Internal Wet Disc
Housing (Case)	Die-Cast Aluminum
Gears	Heat-treated Powder Metal Heat-treated Steel gears available as optional upgrade
Differential	Automotive-type Bevel Gears
Speed Control System	Foot Control: Dampening system or external shock absorber available Hand Control: External friction pack and lever available
Bypass Valve (Roll Release)	Standard
Hydraulic fluid Type	Proprietary Tuff Torq Tuff Tech drive fluid recommended. (Contact OEM for other options)

Edited February 13, 2019 by bcgold

[JoeM 7,871]

Only worked on one Tuff Torq K58 in my son's 4 wheel steer x324. Axle seal started leaking. at 350 some hours.

Interesting piece of work. No gasket in the case and uses motor oil for the hydro and lube. Looks very well built, other than no drains in pan. I ordered a kit and installed, doubt if we ever change it being a closed system. The OEM oil was very dark but had little dirt. I used 15w40 synthetic oil and Permatex black to seal. This mower was purchase at a JD dealer, it has steel gears and was big bucks!

 

 

[bc.gold 3,403]

Deere's infamous K46 powdered gears totally worn out.

 

Our Deer LA 175 a drain on the pocket book, should have bought a boat instead of an anchor.

 

 

 

[bc.gold 3,403]

Here;s what makes the Tuff Torq K66 a desirable replacement for the K46. Heat treated steel gears, looking for a suitable donor.

 

Tuff Torq Corporation > Products > Lawn & Garden > Integrated Hydrostatic Transaxles (IHT) > Professional > K66

 

The K66 is not just an upgraded version of our popular Residential series of transaxles.  These drive systems have been engineered from the ground up for the demands of heavier and more function-rich mower and tractor applications.  Bigger and stronger pump and motor systems have been integrated to offer the power and control needed for bigger lawns and heavier loads.  These units also include heavier axles, more gear options and better control flexibility.  The K66 is an excellent choice to larger premium yard tractors and estate tractors.

Features

• Patented L.O.G.I.C. case design for easy installation, reliability and serviceability.

• Heavy steel axles for added strength and control.

• Manual locking differential system (optional).

• External hydraulic accessory support and charge pumps (optional).

• Larger pump and motor displacements provide the torque you need for ground engaging equipment.

Specifications

Specification	Value	Units
Application	Yard Tractor Estate Tractor Light-Duty Garden Tractor
Reduction Ratio	37.22:1  22.19:1
Axle Torque (Rated)	37.22:1 = 420 (310)  22.19:1 = 250 (185)	Nm (lb-ft)
Max. Tire Diameter	37.22:1 = 584 (23)  22.19:1 = 457 (18)	mm (in)
Brake Capacity	37.22:1 = 330 (243)  22.19:1 = 216 (159)	Nm (lb-ft) @ 300 N (67.5 lb) Brake Arm Force
Displacement (Pump/Motor)	10/10	cc/rev
Max. Input Speed	3,400	rpm
Axle Shaft Size	25.4 (1.0)	mm (in)
Weight (dry)	23 (50.7)	kg (lb)
Brake Type	Internal Wet Disc
Housing (Case)	Die-Cast Aluminum
Gears	Heat-treated Steel Gears
Differential	Automotive-type Bevel Gears
Differential Locks	Automatic ETC differential lock option  Manual differential lock option
Speed Control System	Foot Control: External Shock Absorber option
Auxiliary/External Hydraulic Outlets	Available option for power steering, lift, etc.  6.9L per minute  31 bars (450 psi) @ 2,000 rpm
External Filter Change	Available option
Bypass Valve (Roll Release)	Standard
Oil Reservoir	External Reservoir (available option)
Hydraulic fluid type	Proprietary Tuff Torq Tuff Tech drive fluid recommended. (Contact OEM for other options)

Edited February 14, 2019 by bcgold

[Sarge 3,463]

But, still - even the better Tuff Torq uses only 1" axles, a weak design along with the aluminum case. That keeps it in the lawn mower class in my opinion and should never be used in a GT class application. There are other iron rear cases, both in hydro and gear drive options that can be adapted. A buddy swapped out his Tuff Torq for a Noma built cast iron rear axle unit with 1-1/8" axles and a gear drive to handle the heavier work. But, in reality, the unibody design of the Deere won't be able to handle much without a lot of reinforcement. His was also the LA175, which at best can only handle lawn mowing duties if you want it to last. A local guy here in town has replaced the Tuff Torq in his twice now, just due to using a snowblower on it and weights. 

 

No offense, but for the cost of that entire series of Deere tractors - you could easily rebuild an older and much heavier GT that will still mow the lawn, but also very easily do heavy, ground-engaging work and outlast these newer, cheaply built boat anchors. Actually, they aren't even good as a boat anchor - they are too light.

To be clear - I also have an LA series here that I inherited from Dad when he died. Since it was his, I've kept it and do mow with it occasionally. It does have some benefits with the foot operated hydro control, but otherwise is basically worthless. This one is the even lighter LA145, when that hydro trans dies the thing will be parted out - just like so many thousands of others. Consumers just don't seem to get it or think the lower price is somehow better - buying a quality made machine that will last is a better investment. They want cheap, easy and quick - these throwaway units last about as long as expected. They die easily due to cheap parts, made quickly and as easily as possible. Don't get me wrong - there are very high-quality options out there but they also come with a price tag to match what a mid-level brand new car used to cost. You get what you pay for, lol.

 

Sarge

[bc.gold 3,403]

No offence taken Sarge, my objective with this thread was to point out powdered metallurgy and it's affects on the consumer grade equipment and how were essentially being robbed with this underhanded slight of hand.

 

There will never be another green machine on our property once this LA175 quits working, besides even as a mower it's not very good at cutting grass even after installing new blades the machine does a poor job.

[JoeM 7,871]

It is the way things are going now. Less build cost matching the market demand, people just want to spend so much. Ground engaging equipment is a smaller market now. People want to buy their vegetables and just cut the grass.

I keep the Wheel Horses around just for plowing, tilling,  you know the hard work.

I will say that JD X324 is a grass mowing machine, the Kawasaki engine never short on power, tight turning radius (I can turn the wheel all the way and make a circle leaves about 12" uncut!), Much easier to get a high quality cut, comfortable but.......will not till. The surprise is it weighs just south of a 520H.

I have a Kubota GR, another grass cutting machine......power steering, 4WD, will not till!

Probably got to get into a sub compact size to get good quality ground engagement.

Figure this why WH tractors have gone by the way side.

[Sarge 3,463]

I agree - using powdered metal for things like those gears in such a high-stress area is a recipe for failure - and trust me, they know it. Intent obsolescence - consumers have allowed this practice to continue by buying this junk and encouraging manufacturers to take the practice further and further with time. There are some powdered metal technology methods that can produce gears that are actually as strong, or in some cases, stronger than standard steel gears - but those have a huge price tag. There is almost no manufacturer today that does not take at least some shortcuts when it comes to parts quality - even the best of them do it to satisfy shareholders. I can take old, very worn out gears from earlier generation drive systems and build up the teeth with TIG welding and using ER80SD2/6 tool steel filler rod. Re-grind the profile and those gears will last a long time with no noise or excessive play. The newer equipment uses such inferior metal content I won't even work on them - that is a waste of my time and the customer's money.

 

That whole LA series of lawn tractors was a rotten joke on the consumer market - and they weren't all that cheap as even the lower models were around $2,300 US. To add to the misery was the Edge series decks - one of the poorest performing deck designs ever made. The powder coating on them falls off easily, they plug up even in the driest conditions and are a total pain in the butt to remove and clean properly. Weak spindles, flimsy shell design and hanger brackets that are designed to wear themselves out in short order were some of the known problems with that series. I will say this - at least the bearings in the spindles can be easily replaced if you take the time to do them, but they are far too lightweight to last very long. I laugh every time I see one of these tractors running around a lawn and leaving such a rotten finish when mowing. I laugh much harder when I see some hapless homeowner towing a heavy yard trailer or trying to use a blade/snowblower on one of these machines - in a few short seasons they disappear and a new, just as-bad replacement brand shows up after these disposable units are thrown away. The values of the older GT's are going up quickly - especially on restored examples for a reason.

 

Sarge

[JoeM 7,871]

On ‎2‎/‎16‎/‎2019 at 9:34 AM, Sarge said:

 The newer equipment uses such inferior metal content I won't even work on them - that is a waste of my time and the customer's money.

 

 

Just try to weld something on these new machines, OMG. The metal is so filled with impurities, I will break out the stick welder. I grabbed an old WH Z bracket out of the junk pile and welded on it, what a difference in the metal. A friend dropped off a cub LTx1045 needing some work, When I went to move the mower deck, I just about flipped it clean out of the shop it was so light. He got a deal on it, they should have paid him to take it.

[squonk 41,022]

On 2/14/2019 at 3:23 PM, OILUJ52 said:

Only worked on one Tuff Torq K58 in my son's 4 wheel steer x324. Axle seal started leaking. at 350 some hours.

Interesting piece of work. No gasket in the case and uses motor oil for the hydro and lube. Looks very well built, other than no drains in pan. I ordered a kit and installed, doubt if we ever change it being a closed system. The OEM oil was very dark but had little dirt. I used 15w40 synthetic oil and Permatex black to seal. This mower was purchase at a JD dealer, it has steel gears and was big bucks!

 

That case was probably sealed with anerobic sealer. Almost invisible on most applications