TuffTorq K46 Repair Guide with Pictures

[jcannon]

Thanks for the original post. I had the same problem and bought the three recommended parts. When the parts arrived I opened the tranny and found the differental gears were also badly worn and missing parts of teeth. Many metal fragments were in the oil. I ordered the diff gear set for about $25. Put it back together this morning and mowed 1.5 acres. Mine needed the priming procedure which took a few minutes before it happened. It works great and cost under $200 and an afternoon of labor. Thanks for posting which parts to buy.

I've seen a lot of posts saying negative things about this transmission but want to defend it a bit. Parts are readily available and it is quite easy to fix, and the parts guy Derrick Dalton was very helpful. Used as intended, I'm betting it easily lasts 10 seasons.

The manufacturer of the garden tractor combined this tranny with plow mounts and a hitch hole. Some people never or rarely use them, but some of us do. I wouldn't have bought a garden tractor without them. I bought the garden tractor, cart and plow at the same time from a big box store. I love that cart and hauled a lot of dirt, rocks, and broken concrete uphill. As much as the machine could pull. After 4 1/2 years the tranny wore out and cost $200 to fix. That's not bad.

 

[lightningrod]

I have the JD L120 tractor with the K46 transmission. The tractor is about 7 years old with 370 hours total run time. I use it to cut about 1.5 acres of hilly terrain AND I use it in the winter with a snow blade to clear my 600 ft drive way. I have definately beat the **** out of that transmission. Mine, like the others is loosing its grip after about 20 to 30 mins of run time.

I drained and replaced the fluid hoping for the quick fix but I got no improvement. SO, thanks to this awesome post with its detailed instructions I ordered the replacement parts and 4 quarts of 5w-50 from the TuffTorq website. Was under $200 total.

Now hopefully in the next couple of weeks I can get back on here post that the rebuild was a total success! Wish me luck lol...

 

[om21braz]

Thanks for the post/repair guide ! It has been great for some here already and I expect it to get plenty of use, nothing like a good how-to with pictures. TuffTorq ought to appreciate the post too.

 

[lightningrod]

Wow, what a chore! Of course, Im no seasoned mechanic or anything I took it apart and put the new parts in this morning. I got quite a chuckle out of the tiny rod (see paragragh below). I dropped it in the case, thought it was lost, used needle nose pliers to rescue it. Its smaller than a freakin tic tac and the tranny probably wouldnt work without it. I felt like a doctor performing brain surgery :laughing: I caught myself saying "If this thing works when Im done with it - I'll be shocked!!" Yep said that a few times today

I also replaced the drive belt while the gasket glue was curing since I had that much out of the way all ready. After It was complete and reassembled, I fired it up, closed my eyes, said a prayer, crossed my fingers and stepped on the go pedal. For brief moment there was no movement, then all of a sudden it lunged forward with reckless abandon!! I ran the heck out of it for about 30 minutes. I climed the steepest hills I could find, even backed it up a few of them, and the transmission seemed not to loose any strength. Yes, Im thinkin we have a bingo :thumbsup:

So Im very happy I took on the challenge. I look at it like I made $400 in 5 hours since a new tranny is $600 and I got less than $200 into the parts.

Part #7 is the larger Motor Cylinder Block which you will replace. It has a number of spring loaded pistons, so remove slowly. CAREFUL, there is a tiny rod in the center of the cylinder that slips in and out. It must be a valve or something. Save this part. Also, there is a washer on one end that goes around the shaft. It sticks to the cylinder and could be easily missed. BE SURE TO PUT THIS ON THE NEW PUMP. Part #8 is a wedge that can be taken out and set aside for reuse

 

[southpawshooter]

I have similar problems with a 2003 L120 and the K46 transmission. I decided to try changing the oil first. I did not drop the tranny, but instead pulled the right wheel and have access to the valve on top. I pulled the rubber dust cap and the plug. TuffTorq description of the parts is the vent valve. The fluid level was approximately 2 inches from the top. I drained the oil with a pump and only got 1 qt. out. The oil is charcoal gray in color. I'm pretty sure the suction tube is hitting bottom and I can hear it sucking air and gurgling, indicating all oil has been removed. TuffTorq lists the capacity as 2 qts., is it possible I have lost that much oil in 7 yrs? Also, when I refill how far from the top should the fluid be?

 

[AKfish]

Excellent post!! :thumbsup: You done way good, Brit! I'd be very surprised if someone doesn't pick this up and send it all over the Net!

Be able to find it on a landscaper site in Europe - next week!

AKfish

 

[stevem5215]

It sure would be nice if we had a method of upgrading the current ones to the external filter and extra capacity storage pans also. Maybe someone could see when they talk to Tuff torq if it's even possible ? I'd do some preventive maint to get longer life out of this K46. Even if i've only had it less than a year so far.

Steve

 

[lightningrod]

I have similar problems with a 2003 L120 and the K46 transmission. I decided to try changing the oil first. I did not drop the tranny, but instead pulled the right wheel and have access to the valve on top. I pulled the rubber dust cap and the plug. TuffTorq description of the parts is the vent valve. The fluid level was approximately 2 inches from the top. I drained the oil with a pump and only got 1 qt. out. The oil is charcoal gray in color. I'm pretty sure the suction tube is hitting bottom and I can hear it sucking air and gurgling, indicating all oil has been removed. TuffTorq lists the capacity as 2 qts., is it possible I have lost that much oil in 7 yrs? Also, when I refill how far from the top should the fluid be?

The fluid in mine was like yours with a charcoal gray color and also about 2 inches from the top. Im thinkin you might only be able to get 1 quart out by using the method you described. There are places in the case where the oil would settle and not make it to your tube. You really need to take the tranny off and flip it upside down to completely drain it. I havent seen anyone post that just changing the oil in the tranny had any positive effect.

When I refilled mine I filled it completely. I used approximently 2 and a quarter quarts to fill it. Im guessing that thru temperature changes and expansion it pushes some of the fluid out during use. Mine did drip out the vent on top for a little while until the fluid level got to a "comfortable" level in the case.

 

[ASQTec]

Great thread! Wish I'd seen it before I ventured into my rebuild.

It may benefit some folks to know that the wedge (part #8 on the pic in the 4th post) can be installed 2 ways; the way it appears in the picture, or 180 degrees out. The resulting actions due to an incorrect install will leave you with your forward and reverse foot pedals sending you tractor in the opposite direction. Don't ask me how I know this.

The rebuild and synthetic oil refill were well worth the effort, as my Regent now pulls like an animal.

 

[LotsofGreenGrass]

Thanks for the original post. I had the same problem and bought the three recommended parts. When the parts arrived I opened the tranny and found the differental gears were also badly worn and missing parts of teeth. Many metal fragments were in the oil. I ordered the diff gear set for about $25. Put it back together this morning and mowed 1.5 acres. Mine needed the priming procedure which took a few minutes before it happened. It works great and cost under $200 and an afternoon of labor. Thanks for posting which parts to buy.

I've seen a lot of posts saying negative things about this transmission but want to defend it a bit. Parts are readily available and it is quite easy to fix, and the parts guy Derrick Dalton was very helpful. Used as intended, I'm betting it easily lasts 10 seasons.

The manufacturer of the garden tractor combined this tranny with plow mounts and a hitch hole. Some people never or rarely use them, but some of us do. I wouldn't have bought a garden tractor without them. I bought the garden tractor, cart and plow at the same time from a big box store. I love that cart and hauled a lot of dirt, rocks, and broken concrete uphill. As much as the machine could pull. After 4 1/2 years the tranny wore out and cost $200 to fix. That's not bad.

Glad to hear it this helped!
Brit