Titan 4WD advice

Pro 4x is automatically going to come with 3.36 gears, which will give you more towing capacity(9300#), usually also always come standard with leather seats. SV will be fine with the lower gears (2.94 7300#) towing the boat. Pro 4x has lockers in the back which will prevent slippage even more so when in 4wd. If you plan on spending time in the mountains, I would go Pro4x, if your staying low, western Washington rarely gets snow low. Personally, I would only have a 4wd truck, only change I would have made about mine is I wish I had the bigger towing gears. I lived in Eastern Washington for 30+ years. You can get the SV (SE 08-11) with the bigger gears, but they are kind of hard to come by set up that way. I would make he decision on your towing needs. Stick with 08-15 those are the better years, most issues have been fixed with earlier models by then