2008 Toyota Tacoma steering problems

While entering an on ramp the truck accelerated on its own going out of control, crashing sideways into a guard rail...once it took off on its own it kept increasing speed on its own, applying the brake had no affect on getting it under control...damage $8,000.00....took to dealer next day to which they found no problem...we have found many instances as this one with this same truck and model on the internet.

I noticed the steering became intermittently stiff, becoming more so about a week ago. It happened while driving in all conditions (slow speed, highway speed, dry weather, wet roads etc) power steering fluid was full, pump was fine. My garage determined that the u joint on the steering shaft was stuck and that I need to replace the steering shaft. This is a 2 part shaft (with u joint) that is only available from toyota. It's costing me $762 to have this replaced. This is a major safety issue.