Tuff Torq K46 Fluid Change: Two Methods, Best Oil To Use & Tips.
Wondering how to change the fluid in your Tuff Torq K46 / T40 hydrostatic transmission or if it's even required? If so, this video has you covered. I'll show how to remove the K46 / T40 hydrostatic transmission from your riding mower, how to drain the K46 oil, how to refill it and what type of oil to use along with tips to help you with the process. I include both the easy K46 / T40 fluid change method and the more involved method to clean the transmission filter, magnets & inspection. The Tuff Torq K46 / T40 is the most popular hydrostatic transmission in residential riding mowers and chances are if you have a residential riding mower with a hydrostatic transmission, it's a K46, or on John Deere's, a T40J. Unfortunately, most mower manufacturers state the oil in these residential K46/T40 integrated hydrostatic transmissions (also called IHT's) are "Non-Serviceable" and contain a "Lifetime Fluid". I'm here to inform you that is total nonsense; unless of course you want the lifetime of your IHT to be short. There is simply no such thing as a lifetime fluid in any riding mower IHT! How to know when to change the oil in your K46 / T40 IHT? Basing fluid change intervals on run hours is the usual method as shown in the video (first change at 50 hours, and then every 200 hours thereafter). If you don't monitor run time, you can base your IHT change intervals on transmission performance, specifically if your riding mower's hydrostatic transmission starts making a louder whining noise whenever you drive forward, reverse or while going up hills (gets worse as the fluid heats up). A little hydrostatic whine is normal, but increased hydrostatic pump/motor whine as the fluid heats up is a good indicator the fluid has degraded or is low and needs to be changed. Additionally, if your riding mower is slipping / drives slower or not at all as the transmission fluid heats up, it may be too late as the hydrostatic pump/motor/center block assembly might have also have experienced accelerated wear (fluid pressure loss). However, changing the hydrostatic oil is the first inexpensive diagnostic option to try in these instances before replacing the transmission or having it rebuilt. Often just replacing the oil will get the IHT working again and slow further pump/motor wear damage. Time Chapters: 0:00 Introduction 2:40 Removing the K46 7:02 Drain Plug Removal 8:40 Draining the Oil 9:50 Full Service Inspection 18:09 Inspect Your Belt 19:31 Filling the Oil 24:14 Installation & Conclusion Videos: Mower Deck Removal / Service Video: • Riding Mower Deck Maintenance - Keep it Ru... Riding Mower Yearly Maintenance Video: • How To Maintain A Riding Mower - Easy DIY ... Tuff Torq K46 Training Video: • Tuff Torq K46 tutorial Product Links: Tuff Torq Website https://www.tufftorq.com/ Tuff Torq K-46 / T40 Service Parts https://amzn.to/3ZOjhJH Tuff Tech Hydrostatic 5W-50 Oil https://amzn.to/46eJghc Amsoil 20W-50 Hydrostatic Oil https://www.amsoil.com/p/amsoil-20w-5... 5W-50 Synthetic Oil https://amzn.to/4l0R7DK 15W-50 Synthetic Oil https://amzn.to/4k7FV6Q John Deere HY-Gard J20C Oil https://amzn.to/4nfC8r7 Oil Drain Container https://amzn.to/44wVajX Ultra Grey RTV Gasket Maker https://amzn.to/3TbUQC5 Tuff Torq IHT Filters https://amzn.to/4bKQITK Tuff Torq IHT M8x1.25 Drain Plugs https://amzn.to/4m86uM1 M8x1.25mm Drain Plug Tap https://amzn.to/41JGkWo Tuff Torq IHT Fill & Vent Cap Kit https://amzn.to/3PIdCmd Handy Hand Drill 1/4", 3/8", 1/2" socket adapter set: https://amzn.to/3ICMcKE K46/T40 Rebuild Service https://www.ebay.ca/itm/284338450460 John Deere L/LA/D110/115/120/125/130/140 GX20006 Transmission Belt (Kevlar or Aramid for longest life) https://amzn.to/44kbKDR DISCLAIMER: This video is for information and entertainment purposes only. It's no substitute for prior mechanical experience and/or training. Links included may be affiliate links. If you purchase a product or service with the links that I provide I may receive a small commission. There is no additional charge to you! Thank you for supporting my channel which helps me keep creating content. Please consider giving a thumbs up & subscribe if you enjoy my content - it helps! / @rchelicopterfun Thank you & thanks for watching :)

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