[TXwaterdog]

OP- thanks for posting this I have the same concerns and I've been battling this for a bit.

Originally Posted by t vago

You may be able to go farther if you put your transmission into neutral while coasting, than if you leave it in gear, but consider this:

Every time you shift from neutral to drive, you're inducing a tiny bit of wear on the friction component of your transmission's geartrain. This is by design and is unavoidable. Also consider that automatic transmissions were designed to be shifted from neutral into gear while the vehicle is not moving, so as to minimize that wear I just mentioned. Shifting the automatic transmission in and out of neutral, while the vehicle is moving forward at a decent speed, is a sure way to shorten the life of the transmission, because you'd be inducing a lot of unnecessary wear in the geartrain friction component of the transmission.

good point. In my 2012 Focus it's actually a maunmatic (automated manual) So I don't have the same concerns as the OP. But I agree with you here. IMO on the XB you're looking at a vehicle not designed to be shifted in and out of gear at speed. Be sure to check if you can flat tow the Scion and what speeds are recommended. If you can't flat tow it, don't shift into neutral while rolling.

By comparison, the lockup torque converter (at least in my truck) is designed to unlock and lock up while the vehicle is in motion, and while a significant amount of power is being fed from the engine into the transmission. My torque converter will alternately lock-up and unlock whenever I am stepping on the gas, then letting off of the gas pedal. However, that isn't going to wear out my lockup torque converter very much, and it's certainly safer than shifting to neutral and back.

Therefore, I recommend that your transmission be left in gear. The small amount of gasoline you'll save by switching in and out of neutral, above and beyond the pulse-n-glide technique I described, isn't worth shortening the life of your transmission, nor is it worth reducing your safety margin of error.

Another good point here. I'm trying to realize what the shift to neutral is gaining me and I think it's actually significant. Next tank I'm going to not neutral shift at all and find out (ok in 2 tanks actually next tank is already claimed for another test phase). I'll report back. I suspect my 34mpg tank was due to no neutral shifts while I'm now getting 38mpg almost all the time.