Too Lock or not to Lock??

The brochure is wrong... been discussed before...

A-TRAC only on the Off Road TRD 4WD, and only on in Low Range, and only 'on' if you select it (button).

Low Range has 4 drive modes:

Standard: Open differentials so the tires that can spin the easiest will spin and the tires that are on firm ground do nothing. [I never use this mode... no advantage over other choices.]

A-TRAC on: All tires have matched rotation via sensors and brakes, so power is shared between good and bad traction tires, steering not affected as sensors will allow differential action and check if traction assist is needed. [This is the choice of 90% of my low range use.]

Rear Locker on (A-TRAC off): Rear tires have matched rotation by gear locking, front tires on open differential, so one will spin if on looser surface, ie. traction loss. Steering is compromised, thus Toyota warns to only use in emergency situations and not over 5 mph. Yes, the truck can drive faster when locked but will not steer as easily since rear tires are not allowed to rotate differently. [I never use this mode, as A-TRAC added offers more traction.]

A-TRAC + Rear Locker: A-TRAC works only on front tires and only if speed drops below 3 mph (ie becoming stuck) by providing front tire rotation matching via sensors and brakes while rear tires are locked via gears. [I use this 10% of the time I use low range... primarily for pulling others out of a stuck or up a hill and also found it effective on snowy roads as there is no braking of non-traction tires unless speed drops below 3 mph. The spinning above 2 mph helps keep tires clean of snow, mud, and ice.]

 

That brochure error discussion was probably before I joined the forum.

However, the brochure error should have been more obvious to me, because not only does it say that A-TRAC is standard on all 4WDs but also on all 2WDs.

Thanks for all the A-TRAC information. Seems to me that A-TRAC is a really useful feature, and would help make the OPs decision easier.