I have a 1997 4Runner, V-6, Auto Transmission, 154,000 miles, and recently aquired (No personal history). Went to get a NYS inspection and it won't pass because it has a pending P0136 and three monitors are blinking on the scanner and you can only have two (Mechanics terminology, not mine). Should I look at replacing to O2 sensors and be done with it or is there something else I should be looking at?

On a seperate note, at 1500RPMs and at about 50MPH the transmission has a hesitation. If I depress the accelerator further I can drive out of it, but if I maintain the current level of throttle it just goes thunk, thunk, thunk. Could this be anything other than a transmission issue? This only happens at 50 MPH at 1500 RPM's. What might be wrong with the transmission? I don't want to go into a shop without the appearance of some knowledge of the problem.

I ahve experienced the strawberry milkshake in another vehicle and got another 20,000 plus out of it after the pan drop, filter change and flush and never had symptoms like this, so I am hoping that this is a different issue.

As always, thank you for your advice and opinions.
Jerry