Zero Turn Mower Transmission Issue

Have a 2017 Gravely Pro-Turn mower. At the first transmission fluid/filter change right transmission fluid was dark brown while the left transmission fluid was clear yellow. I thought it was a break-in issue but now after 50 hours post change, a sample of the right expansion tank fluid shows dark brown already while the left side fluid is clean. Dealership salesman says this is not uncommon and nothing to be concerned about. I see a potential expensive repair down the road. Has anyone out there had a similar issue with a zero turn mower?

Welcome to the forum! :welcome:

I'm going to move this thread over to our Gravely section to see if we can find you some answers.

https://support.gravely.com/article/?id=62028198-ca7f-e711-80f4-c4346bad526c

is mower still under warranty? i would let dealer service transmission if mower is still under warranty. if it would ease your mind contact Gravely headquarters & let them know about situation & what you were told.