Thanks inafogg. I really feel like it's a good guess too. Before I begin today I will attempt to speak to someone at the Toyota factory service center here in Dallas to see if they think its a good guess also. We'll see if they talk to me. I know it sounds cheap, but I'm really at the point that being wrong about a $35 tube would hurt. I wonder if there is a way to evaluate the tube after removing it before I buy the new one.