My Toro transaxle recently began slipping in forward and would barely go and slip going down hill. Reverse was fine. After taking it apart I found that the shift fork was worn on the side, more so in the reverse position. The outer sleeve bearings were nearly wore out. This is with only 200 hours. All the gears were in excellent condition with no visible wear.
Using the manufactures assembly diagram (https://www.toro.com/en/parts/partdetails/?id=30272 ) I discovered that a washer was missing on the drive shaft (#8 part: "1125945" on the schematic and it was never installed at the factory) also there seemed to be excessive side play on the drive shaft. I ordered more shim washers (#3 on the schematic, they come in three different thicknesses, not specified in the parts list). I ordered one of each 112-0745, 112-0748 & 112-0750. Since there were already two installed on the right side of the drive shaft from the factory I had extra for shimming.
As it turns out #8: 1125945 (correct part number) did not fit the splined shaft and had to be ground out larger (washer is hardened). I added this washer to position 18 and moved one of two from position 20 on the right side of the shaft to position 3 on the left side. Two shims at position 20 were too much with the addition of #18. I also added a thick version of #3 and a thin version to position 3. This put a total of 4 washers on the left side. This left a little bit of needed side play. By clamping the case together and testing the rotation of the input shaft everything rotated as it should.
I tapped the case and added 2 grease zerks on the bottom side in the middle of the sleeve bearings. This should keep the outer sleeve bearings lubricated and from wearing out so soon. I lubricated all moving parts and refilled the case with 20 ounces of manufacture specified lube (NLGI "0" grease). This was obtained by contacting a Toro dealer. I used John Deere Corn head grease which is easy to obtain locally and was less than $4 per 14 oz. tube.
Others, including manufactures have suggested using Bentonite grease, it costs around $30 for 32 oz. not including shipping. I elected to go with NGLI "0" grease because it is easy to get, cheap and I can use a grease zerk to put more in. I assemble the case with RTV silicone, but not between the axle and inner cavity of the transaxle. After assembly, I pumped more grease in between the sleeve bearings, about 50 shots each side, since extra would just go in to the case. I ended up using both tubes of grease I bought, 28 ounces.
In addition, I disassembled the mower spindles--cleaned up the bearings. There was little sign of grease and each one had moisture damage from washing my mower deck. After repacking the bearings, I left the inner bearing seal off. I tapped the spindle and added a grease zerk and then pumped in marine grade EP lithium based NGLI "2" grease. The idler pulleys on the mower deck were running rough and so I removed the seals on them, cleaned and repacked. Everything runs much quieter and smoother. After 4 hours of operation the mower is going strong.
After seeing the moisture damage cased to poorly sealed bearings from under deck mower washing, I will rarely wash my mower deck, even running it after washing does little to remove moisture from bearings. I will just treat the underside with used motor oil, mow when dry (if possible) and periodically scape off the buildup. Debris that gets on top of the mower will be blown off with an air compressor....
I hope this helps someone else in maintaining and keeping their mower going. I spent about $80 in parts and lube, better than the $300 for a new transaxle, that won't be any better than what I have now.
Using the manufactures assembly diagram (https://www.toro.com/en/parts/partdetails/?id=30272 ) I discovered that a washer was missing on the drive shaft (#8 part: "1125945" on the schematic and it was never installed at the factory) also there seemed to be excessive side play on the drive shaft. I ordered more shim washers (#3 on the schematic, they come in three different thicknesses, not specified in the parts list). I ordered one of each 112-0745, 112-0748 & 112-0750. Since there were already two installed on the right side of the drive shaft from the factory I had extra for shimming.
As it turns out #8: 1125945 (correct part number) did not fit the splined shaft and had to be ground out larger (washer is hardened). I added this washer to position 18 and moved one of two from position 20 on the right side of the shaft to position 3 on the left side. Two shims at position 20 were too much with the addition of #18. I also added a thick version of #3 and a thin version to position 3. This put a total of 4 washers on the left side. This left a little bit of needed side play. By clamping the case together and testing the rotation of the input shaft everything rotated as it should.
I tapped the case and added 2 grease zerks on the bottom side in the middle of the sleeve bearings. This should keep the outer sleeve bearings lubricated and from wearing out so soon. I lubricated all moving parts and refilled the case with 20 ounces of manufacture specified lube (NLGI "0" grease). This was obtained by contacting a Toro dealer. I used John Deere Corn head grease which is easy to obtain locally and was less than $4 per 14 oz. tube.
Others, including manufactures have suggested using Bentonite grease, it costs around $30 for 32 oz. not including shipping. I elected to go with NGLI "0" grease because it is easy to get, cheap and I can use a grease zerk to put more in. I assemble the case with RTV silicone, but not between the axle and inner cavity of the transaxle. After assembly, I pumped more grease in between the sleeve bearings, about 50 shots each side, since extra would just go in to the case. I ended up using both tubes of grease I bought, 28 ounces.
In addition, I disassembled the mower spindles--cleaned up the bearings. There was little sign of grease and each one had moisture damage from washing my mower deck. After repacking the bearings, I left the inner bearing seal off. I tapped the spindle and added a grease zerk and then pumped in marine grade EP lithium based NGLI "2" grease. The idler pulleys on the mower deck were running rough and so I removed the seals on them, cleaned and repacked. Everything runs much quieter and smoother. After 4 hours of operation the mower is going strong.
After seeing the moisture damage cased to poorly sealed bearings from under deck mower washing, I will rarely wash my mower deck, even running it after washing does little to remove moisture from bearings. I will just treat the underside with used motor oil, mow when dry (if possible) and periodically scape off the buildup. Debris that gets on top of the mower will be blown off with an air compressor....
I hope this helps someone else in maintaining and keeping their mower going. I spent about $80 in parts and lube, better than the $300 for a new transaxle, that won't be any better than what I have now.