SamHit 14 #1 Posted 7 hours ago I am turning my C175 into a mud mower. I swapped both pulley’s so that it goes faster. The transmission fluid is milky (I attached a photo of the dipstick) so I wanted to drain it, and refill it with new gear oil. Should I be using 80W-90 or 85w-140? I’ve seen both mentioned, and I wasn’t sure if I should be using one of those, or something else since I will be reaching higher speeds than the 8 speed normally goes. Thanks for the help Share this post Link to post Share on other sites
ri702bill 13,098 #2 Posted 4 hours ago IMHO - Flush the Unidrive with Diesel fuel first. Two quarts will do it - run it thru all the grears, Hi and Lo. Raise the front of the tractor - by the frame - until the front wheels are off the ground a foot or so... that allows all the fluid to get over the internal hump on the bottom of the case. Look at what comes out - if still milky, it needs to be done again. Let it drain - completely - a couple of hours should do it. Now is the time to inspect all 4 of the oil seals for leaks - replace as necessary. The Full Synthetic 80W-90 would be a good choice for the higher than normal speeds & loads that you mentioned. How is the shifter boot?? That may be where the moisture got in. Replace as necessary. Share this post Link to post Share on other sites
sqrlgtr 4,015 #3 Posted 3 hours ago If it's going to be a mud mower I would run the cheapest stuff I could find and change it often. Share this post Link to post Share on other sites
ri702bill 13,098 #4 Posted 1 hour ago 1 hour ago, sqrlgtr said: If it's going to be a mud mower I would run the cheapest stuff I could find and change it often. Another good way to look at it... particularly if breakage is frequent & expected. 1 Share this post Link to post Share on other sites
pfrederi 21,189 #5 Posted 8 minutes ago What is a mud mower??? Share this post Link to post Share on other sites