TuffTorq K46 Repair Guide with Pictures

[RBLapham]

Going in opposite directions is normal if not on ground. When on the ground you can push the tractor so both wheels move the same direction, hard to do if trans cold - easier if warm. This with the free wheel not pulled, in the run mode.

 

[rburke65]

Well that's good news! I'm going to go put this in then. Thanks for your help.

 

[Voyager6]

On post #83 the OP says.....I found it also helps in the initial test after the rebuild to gently roll both tires in the same direction to get the unit moving again. I am getting ready to reinstall the rebuilt transaxle and I notice that I cannot rotate both axle shafts in the same direction! Each goes in the opposite direction!! Did I do something wrong? Am I in trouble? Thanks again guys....

The roll the tires in post #83 is subject to interpretation on what he meant. It appears to be related to bleeding the hydraulics after rebuild and filling with fluid. It could also be interpreted as needing to move the gears in the case after rebuild to get things to settle out, but generally, the case won't close properly if any of the gears are not properly aligned. My comments are on the former possibility.

1. Once filled with fluid, the freewheel lever needs to be pulled to manually rotate the tires in the same direction with the input shaft non-driven. With the freewheel lever in the drive position, Hydraulics will prevent you from moving the tires the same direction, or it will get difficult in short order. Remember, it is considered bad for the transmission to push the tractor without pulling the freewheel level. Same issue.

2. The opposite direction movement of the tires is the design of the non-locking differential. With the drive gears unable to turn due to hydraulic lock, when you turn one wheel, the differential transfers the power to the other wheel in the opposite direction.

3. The bleeding process generally entails installing the transmission in the tractor and running the engine while the rear tires are off the ground. At that point, with the freewheeling lever in the drive position, the tires should eventually rotate in the same direction when the motion lever (forward/reverse) is pushed. Some people have done this with a drill on the input shaft while the transmission is still out on the bench. In my case, I waited three days after I filled the transmission with oil before trying to run the transmission and no bleeding was required. I had full power from first operation. Your experience may be different.

 

[wactbn]

I have spent a lot of time looking at Tuff Torq's parts site and have observed the following:

The motor and pump are now the same between K46 and K58. In the past, the K46 may have had slightly lesser design motor and pump). The K58 has heat treated steel gears standard. The input shaft and bearings are heavier duty to be able to stand more load back to the engine. Fan and pulley are different sizes (actually there are two fans for K58, one where the fan is on top of the pulley, and the other when it is below the pulley).

As mentioned, it has the charge pump standard. It always came with four magnets and the new design filter. It has heavier duty differential gears and a larger (more teeth) reduction gear to get more torque out to the wheels. This can be seen in the exploded view on tufftorgservice's web site. It has a slightly larger case than the K46, so it holds more fluid. The K58H has hydraullic output and has an external resevoir and externally changable filter (tank and support have be be bought from Deere). The K58H has drain bolts, but the K58A, B, M and N do not, but drain starter locations are pre-drilled inside the lower case cover. Axles are 1" versus 3/4". Not a big deal, but bushings are larger to accomodate this and thus have more wear surface and it can take a bigger load. Unfortunately, the play in the axles/differential appear to be about the same. Shims could be used to keep things together better.

The motion (forward/reverse) lever is further out from the center line of the transmission and the front mounting holes are in a different location due to the larger case. This I learned from personal experience in upgrading my X304 from a K46 to K58. The linkage is adjustable and the K58 front mount is available from Deere for about $3.

The K57 upgrade for the K46 retains the K46 less-durable final drive, reduction, and differential gears and 3/4 inch axles. Most everything else is upgraded to K58 level parts.


Voyager6

Thank you so much for the info! No one has been able to adequately answer these questions before. I'll definitely be doing the charge pump upgrade on my K46AC at 500/600 hours. I currently have 380 hours and it gets regular duty mowing my hilly 1-acre yard and snowthrowing 50-75 yards of driveways in the winter.

 

[joebob]

Hi Guys;
Jim Orr is starting a lawsuit against Deere, & needs signatures of people that have had probs. w/ the K46 tranny. Maybee we can get something for all our grief.He had about 18 sigs. so far, & needs a few more to total 25 to get started. C'mon guys sign up. He's at.....jumbo1114@hotmail.com
Joebob

 

[joebob]

Hi Guys;
Jim Orr is starting a lawsuit against Deere, & needs signatures of people that have had probs. w/ the K46 tranny. Maybee we can get something for all our grief.He had about 18 sigs. so far, & needs a few more to total 25 to get started. C'mon guys sign up. He's at.....jumbo1114@hotmail.com
Joebob

 

[ehb]

Hi again,

again, thanks for the information in post 590, Voyager6!
I'll be looking for a K58H now for my 70s John Deere that's awaiting restoration. Great info!

Parts I would need to make this transmission good-as-new again would be way over 500€, so I'm not going full monty on this, only replace the absolute necessary, clean everything and adjust all the clearances.

I have sent an email to Derrick asking if there is a steel version of differential gears for the K46. He just replied, but there is none. So I'll stay with the sintered differential gears and order them now (along with the axle bushings, which are cheap).

Speaking of which: I was trying to shim out the gears today (and will have measurements soon), but was unable to do so with the differential gears. No matter what, the final drive gear is too wide to let the pinion gears ever get in full contact with the side gears. They can always move about way too much. I will wait for the new parts and see if they fit better, else they will have to be ground down to get tighter together.
I'm still completely lost why there's so much play by design in there.

I also sanded down the wear of the center case with 1200 mesh paper, then gave it a little polish. Looks good now! Great idea. Yes I left a barely visible ring on the pump side, but I lost motivation. Also, a tiny bit of roughness is good to keep an oil film on.


The underlying surface I use for my sandpaper is glass out of an old (as old as possible!) computer scanner. They're reasonably thick and of perfect flatness, and free. I didn't sand the pump or motor, but carefully deburred the edges of their kidney ports with an oilstone. Maybe this helps in not eating up the center case faces.


I tried to remove the two valves from the center case with a neodymium magnet and some strokes with the back of a screw driver. They came out no more than 1.5mm and had scratches, looking down into the center case. So I pushed them back in, still unsure of their function or if they even should come out.

Will keep you posted...

Good luck with the lawsuit, it's a joke JD sells this unit with no way to service. Glad my K46AM did not come with a JD.

Greets,
Stefan

 

[rburke65]

It's me again! You guys probably didn't recognize because of the 'face concealing' smile on my face....I am ALL smiles. Reinstalled Therese end, purged by doing the forward/reverse with both in neutral and engaged while on jack stands. The rear wheels started to move almost instantly as I tried to preload the 2 'revolvers' with some oil. Once on the ground.....OMG.....this thing almost did wheel stands. The torque was amazing. Previously, I couldn't climb the gravel drive from the pole barn up to the front yard at full throttle. Now, at an idle, NO PROBLEM!!! Thanks to everyone who held my bald through this procedure. I also took the advice and others and I installed the 2 drain bolts and from Jim Orr, his idea of the 'fill' tube....also I was the #18 on Jims list for the lawsuit. Thank you, thank you, thank you one and all for all the help.

 

[pooleo]

welp, my rear end took a **** on me, again. It has plenty of function with no weight on the machine (moves great by itslef) but as soon as you get on it, it just wont go. No moaning noises this time tho, or grinding. just nothing. Would a higher viscosity oil help any...?

 

[RBLapham]

Go over to the paper mill and get some *%^#. Or to Getty street
No I once had a peerless transaxle and tried with 120W and it didn't help, even tried trans stop leak. Synthetic 5W50 is the best oil to use. Did you do a rebuild? or what have you tried?