We have a 99 a Newmar Mountainaire with the V10. So far no major issues. Engine and Transmission have been great. Syn oil and trans fluid. Oil change once a year or 7500 unless I am in the mountains a lot. Trans is change out every two years along with the jack fluid which is the same as Trans. Gen is also syn so once a year. Water leak only two since we have it. One, the bath sink cracked and was replace with a home version and gray water drain same thing, crack and several hours working in a very tight space to cut out and put in new back to hose connectors. Rides good and wind does not blow it around. I did put on Air bags to stiffen up the suspension. Ride was too soft.