The D170 i believe has a K46 hydrostatic trans. They are notorious for crapping out. They usually start whining and the whining will get worse and the tractor will lose speed and not want to move uphill. The whining is the fluid bypassing the pistons in the pump. You can get the parts from tuff torq to rebuild it but if not comfortable rebuilding a hydrostat might be a challenge.
<p>OEM Tuff Torq repair kit part number 1A646099601, replaces part number 1A646099600. For K46BE transmission numbers 7A646084120 or 7A646084121. Includes piston/cylinder assemblies, center case, seal & filter kit with sealant and 3 liters of Tuff Tech oil. May also fit others, if you are unsure...
I wouldn't spend a lot of money on that K46. Mine started failing at 300 hrs, split the case, cleaned out the shrapnel, replaced the oil with regular old 10w40 and babied it for another 300 hours. Replaced it with a Peerless 2000. Couple good reads here:
OK guys. I have a 2012 Husqvarna YTH 22V42 lawn tractor with 340 hours on it with the "DREADED K46 TRANSAXLE". I noticed that my transaxle was starting to growl & whine and wasn't operating up to standard especially going uphill. After reading tons of "gloom & doom" posting...
I have rebuilt a couple K46's over the years for customers. Relatively new JD mowers that were worth fixing. Lots of talk on the web about the craptacular K46. Some folks have gotten more life by changing a thicker oil. According to "some guy on the internet" tuff torq ships the trans dry and the mower mfgr installs the fluid they want. Supposedly TT won't warranty the JD trans because they don't use the TT fluid and use a thinner oil. Oddly enough i see more failed K46's on JD mowers than others. Not sure about that because TT specs 3 different oils in different K46 transaxles. One of which is Hy-Gard Hi Vis. I have put 20w-50 in a whining one and it got by for a couple years. Paying a shop to rebuild one, if you can find a shop that can and will do it, will probably cost more than the mower is worth. None of the JD dealers around me will rebuild mower engines or transaxles. They will just replace them. I just finished doing a engine rebuild (hone cylinder, new piston & rings, new valves, etc) on a Kohler CV15 on a JD GT225 that 3 dealers would only replace the engine for big $$$. Told him he would be better off buying a new mower.
Yes the oil used is part of the problem as it should be 20w50 synthetic. Another problem is that they are not designed for towing which is very rough on them.
I only had two failed K46 in the shop so far. Both were before I had a distributor that I could get the Tuff Torq parts through. One the center section failed but that was related to a leaky axle seal and the other was broken axle. Both were more expensive to repair than replacement of the K46 since they are only 175-240 usd more than rebuild kits, retail and about 150 usd cost. So to install a new transaxle the labor is a lot less so it becomes more economical to replace than rebuild. One hour vs two to four hours.
Anyways I agree by the time the transaxle fails most mowers are fairly ragged out and not spending nearly a thousand dollars on it.