Have no personal experience with Mahindra, but have heard of some serious issues with parts availability.
Not had any issues with parts on my current and previous Mahindras. Mostly they are in the warehouse in Houston, and if a dealer needs a part, they next day it to them. The one exception was my air ride seat. They had to get it from India, and it was a couple of weeks. Probably because there's not much call to replace them.
Most of my Mahindra parts are in stock at the dealer, or next day.
