My wife's 2005 4WD Toyota Tacoma pick-up has four Michelin LTX A/T2 tires, size 265/70R16, purchased by her late husband. Although they have 48K miles on them, the thread wear is pretty decent with 6-7/32" (4.5 - 5.5mm) remaining. I noticed, however, that they have been squealing when making the sharp turn onto our asphalt driveway, and last week she had severe fishtailing on a wet asphalt paved road. In digging through her paperwork I discovered the tires are actually nine years old. Could the age of these tires alone cause the apparent loss of traction we are seeing? If so could you recommend good quality replacement tires? The truck does little hauling and is driven fairly gently, seeing about 70/30 of paved vs gravel roads in a hilly environment with a few snow and ice storms each year (Appalachian Mountains of southwestern Virginia at 2,500 - 3,200' elevation). The gravel roads can sometimes be a bit rough and steep and it is not uncommon to have to park on grass. Thanks!