The 2005 onwards TRX500 are good machines. The 2005-8 manual models do chew out first gear if towing a trailer a lot, this was generally fixed up though when the motors got a freshen up. Mines done nearly 38000kms and going strong, its been serviced every 100hrs from new though. It's a bit of a tractor compared to current stuff, never had an issue in the rough as long as being sensible.
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