Tufftork K46 Transmission problems??

[mechanic]

Has anyone experienced any transmission problems with the Tufftork K46 transmission on any of your lawn tractors? I'm thinking about buying a Snapper NXT2346 Model:2690847(23hp,46") for $1999 which has this transmission. However, in past discussions on this forum, I thought there were some issues with this transmission. Please comment. Thanks

I have a Tufftork under a 50" Husqvarna that is 2 years old. Don't remember if it is a 46, but in my opinion I will never buy another mower with that transaxle under it.

 

[danwengard]

I have a husquvarna with a tufftorq k46 trans.i rebuilt it with new parts.worked good for 2 weeks.its a total piece of crap.

 

[LGT2654]

Does anyone know if there is a retro-fit to a better transmission? I bought a Husqvarna LGT2654 from Lowes a few years back. I'll say it has a short duty cycle of about 1 to 1 1/2 hours. It starts with power (and less full speed than when it was new), then looses power during that time. I cut 2 1/2 acres. My lawn goes from slight grade to steeper grade. Now, I cut the low grade first.

The higher grade will cause the Garden (bs) tractor to quickly loose power to the point of not moving. So, I don't know the real problem. The transmission shows no signs of leakage. I'm questioning if the heavier loads are causing the transmission fluid (oil?) to over heat and loose viscosity??? Should the oil be replaced? Would a higher viscosity oil (thicker oil) improve performance or cause transmission damage?

I appreciate any help. Thanks.

 

[tom3]

Long read but full of good info here:

https://www.tractorbynet.com/forums/parts-repairs/164892-tufftorq-k46-repair-guide-pictures.html

If you are handy a clean out and oil change will prolong the agony some. But these hydros use the same oil for the differential gears and the hydraulic unit. Those gears are made from pressed metal and not up to the task for this, metal particles shear off and grind up the hydraulic unit, losing pressure and power. You'll see this in the old oil and the magnets will be plastered with filings. I put a Peerless 2000 unit in my Deere last summer, took some work and fabrication, works fine so far but it sure is noisy. And they called this model a Silent Trac. Must have a sense of humor over at Tecumseh.

 

[bertsmobile1]

Does anyone know if there is a retro-fit to a better transmission? I bought a Husqvarna LGT2654 from Lowes a few years back. I'll say it has a short duty cycle of about 1 to 1 1/2 hours. It starts with power (and less full speed than when it was new), then looses power during that time. I cut 2 1/2 acres. My lawn goes from slight grade to steeper grade. Now, I cut the low grade first.

The higher grade will cause the Garden (bs) tractor to quickly loose power to the point of not moving. So, I don't know the real problem. The transmission shows no signs of leakage. I'm questioning if the heavier loads are causing the transmission fluid (oil?) to over heat and loose viscosity??? Should the oil be replaced? Would a higher viscosity oil (thicker oil) improve performance or cause transmission damage?

I appreciate any help. Thanks.

Trannies have no seals so rely on very close fit between moving and non moving parts to allow the oil to maintian a seal.
Very small amounts of grit in the oil quickly destroy the surface finish.
Note the previous poster who rebuilt his & it failed in a very short time. This would have been due to dirt & dust that got in during the work.
When I do a tranniy it gets degreased, pressure washed, soda blasted then washed again and that is before the first bolt gets taken out.
The dissasembly gets done in the bathroom only after the room has been hosed out and the door is kept closed the entire time the tranny is in there.
If I have to leave then even in the "damp room" the open box gets covered with a damp shop towel.

Contry to what most posters write the usual culprit for early failure is running the engine too slow rather than controlling the speed with the foot pedals.
Hydro boxes need FULL PRESSURE & FULL OIL FLOW at all times to work properly

The second biggest killer is heat, the box needs to be kept clean and the fan must be in good condition, have all of the blades intact and actually be connected to the input shaft.
I could not count the number of times I get under a mower, grab the fan to find it rotating freely on the shaft because the splines have flogged out or the bolts fallen off.
Then there are the boxes that have enough dirt on them to grow potatoes .

So start by getting under & giving you box a good clean, air is better than water unless you take it out.
Then check the security of the fan.
A loose drive belt will also cause the tranny to loose power as it heats up so check the belt for damage and all of the pulleys.
Not uncommon to find a frozen idler on a quite new machine.

A badly worn box can have it's death postoned by going to a heavier oil but most really need the fully synthetic oil and finding it in heavy grades is not easy.
I have had some luck using Syntrans 70-90 which is equivalent 30-60 engine oil as tranny oils use different scales to engine oils.