Razkid 68 #1 Posted December 3, 2016 Today I was changing all of the fluids and filters on my "new" 520H. As I started to drain the transaxle I noticed the smell of gear lube. I have no idea how long it had been in there but the tractor seemed to move alright with it. The previous owner told me he used Mobil1 in the engine and gear lube in the transaxle. I just figured his memory was a little cloudy but it turns out he was right. I'm letting it drain overnight and will install a new filter and dino 10W-30 tomorrow. I plan on running that for the winter and in the spring will drain it, replace the filter and use Mobil1 to refill it. Does that sound like a good plan and is there anything else I should be concerned about or do differently? 1 Share this post Link to post Share on other sites
shallowwatersailor 3,213 #2 Posted December 3, 2016 (edited) I think that I would drain it, add the dino 10W-30 but don't change the filter yet to run it for an hour, drain it again. Possibly consider doing the dino again to be sure; or putting Mobil 1 with the new filter on now so that you can take advantage of the synthetic for winter use. The good thing is that it wasn't water or grease that are harder to clean out. Edited December 3, 2016 by shallowwatersailor 1 Share this post Link to post Share on other sites
WVHillbilly520H 10,374 #3 Posted December 3, 2016 Remember there will always be residual fluid in there that won't get drained unless splitting the transaxle case, and in the lines to the lift cylinder and pump, I personally would use a cheap dino 10w30 2 or 3 times (with new filters each time) with running it around and using the lift multiple times before settling to use through spring just my good luck,Jeff. 5 Share this post Link to post Share on other sites
pfrederi 17,902 #4 Posted December 4, 2016 Synthetic is expensive. I would do a couple of refills with Walmarts or TSC stuff. first. 1 Share this post Link to post Share on other sites
953 nut 55,887 #5 Posted December 4, 2016 As you have not had a problem in spite of the PO using gear oil I would be inclined to agree with your plan of action. The little bit of residual gear oil will be substantially diluted by the new 10W30. 2 Share this post Link to post Share on other sites
Razkid 68 #6 Posted December 4, 2016 14 hours ago, pfrederi said: Synthetic is expensive. I would do a couple of refills with Walmarts or TSC stuff. first. That's why I will go with the dino oil first $$$$$ ! The new axle seals have arrived so I'll go try my luck at getting the hubs and keys off before adding the new oil. Thanks to everyone. 3 Share this post Link to post Share on other sites
Toro Bill 10 #7 Posted December 7, 2016 Wonder if he did it for a reason? Some old timers would change to heavier oil to make a leak stop. Either way your about to find out. I say your plan sounds fine, I agree with 953 Nut. On a side not my PO also ran Mobil 1 10w-30 in both the engine and transaxle, on cold winter days it takes a few minutes for the lift cylinder to activate, without side tracking this thead, I wouldn't worry about running dino oil for the winter, just let it warm up a bit before working it hard. 2 Share this post Link to post Share on other sites
JERSEYHAWG / Glenn 4,497 #8 Posted December 7, 2016 3 hours ago, Toro Bill said: Wonder if he did it for a reason? Some old timers would change to heavier oil to make a leak stop. Either way your about to find out. I say your plan sounds fine, I agree with 953 Nut. On a side not my PO also ran Mobil 1 10w-30 in both the engine and transaxle, on cold winter days it takes a few minutes for the lift cylinder to activate, without side tracking this thead, I wouldn't worry about running dino oil for the winter, just let it warm up a bit before working it hard. Toro Bill, welcome to there's no sneaking in here............ Glenn Share this post Link to post Share on other sites