Transmission Not Engage problems of the 2008 Toyota 4Runner

I have a 2008 4runner. I have always been happy with the vehicle, however, when shifting from reverse to drive the transmission does not engage immediately. This morning I was backing out of the post office where there are always people walking in front a nd in back of your vehicle. I shifted into reverse back up then shifted into drive. When I pressed on the gas the car continued to go in reverse. This was very scary. I pressed on the brake and looked down to make sure I was in drive. The car was in drive, I then pressed the gas again, the car waited about 5 seconds and when forward with a burst of energy. I have had this happen before but not with this distinction. I feel this is a definite safety issue, especially in a parking lot where people are walking constantly.

2008 Toyota 4runner sport - when shifting from reverse to drive the transmission does not always engage. Estimate about 15-20% failure. For about 5 seconds the vehicle acts as if in neutral. If I do not realize what is happening and apply gas, when it finally engages, the car dangerously lurches forward. Fairly sure it is an electronic issue. Has occurred since purchase. Have taken to dealer 3 times. Responses 1) can't repeat and can't start changing parts because may trigger lemon law, 2) can't repeat and no one else has reported, 3) can't repeat, so we will look at it again when you bring in for next oil change. Despite my explaining repeatedly that this is a serious safety concern dealer has shown no real interest to resolve. My home's driveway is on a blind curve and I will not back into road because I can not be sure I can accelerate when needed. This has repeated regularly since purchasing the vehicle over a year ago. I have had a couple of close calls in parking lots and it is inevitable that I will be rear-ended if this is not resolved.