Change direction to (fully) unlock front hubs?

Several times this winter, I put my truck in 4hi at the start of a trip, then after a mile or so I was off the steep stuff and able to go back into 2wd; however, the truck got crappy gas mileage for the entire run, as though it was still in 4wd. Can't tell if that was just coincidence, or if the front auto-locking hubs on these trucks work like the ones on my 83 Bronco did, where you have to drive briskly in reverse for 10-15 feet after shifting back into 2wd to get them to fully disengage. That would make sense, based on the MPG I was seeing - if I was passively turning the front diff and driveshaft during the entire trip, that would explain why I got 13 mpg instead of 20. My old Bronco's manual explicitly called out the need to back up to release the hubs, but the Taco manual doesn't say anything about this, unless I missed it. I played around with shifting in and out of 4hi, and I do think I can hear the hubs releasing when I back up after shifting from 4hi into 2hi, but I might just be hearing what I want to hear.

Anybody have any technical insight?

 

It is on the fly, you do not have to back up to disengage. Maybe the poor mileage was do to Cold Temps, Winter Blend Fuels, Driving Slowly, etc... The light on the dash should also Flash if it won't Disengage.

 

No locking/unlocking hubs on the Taco, front axle basically splits in half via a splined sleeve and the transfer case disengages the front driveshaft when in 2HI.

 

Here's an excellent video detailing the Toyota Tundra 4WD system (more or less the same thing):

https://www.youtube.com/watch?v=47m7QAPrpsI

 

Thanks, all.

 

Lemon Law