I had a Montana I purchased new in 2010. The axles bent. I replaced axles & bushings I t wasn't long till the second set bent. Montana's are too heavy for axles rated at 6750 lbs. That said save your money and take it to Mor/yde in Indiana and get your self I S suspension and disc brakes. Then buy yourself G614 Good year tires. If you take my suggestion but buy the tires first it will be painful as you will be ruining the new tires. By the way the Montana had an absolutely beautiful ride and stopping ability with the I S suspension and disc brakes. The people at Mor/yde are the finest people in my RV dealings.
For what it's worth.