when should i change my timing belt for my sequoia 2007

According to the Toyota Normal Service Schedule,the Timing Belt should be replaced at intervals of every 90,000 miles. Although the timing belts on these vehicles will live well past 90,000 miles, it's a preventative maintence item, and to enusre the life of the vehicle, it should be done. If this belt is to break while under load (going uphill, highway speeds, etc) this will cause internal engine damage resulting in a much higher repair bill. So, better to be safe than sorry!