My new 2015 Limited 4wd 4runner is in route to the dealership but i just read something that makes me think the 4wd system on it will be inferior to my current Tahoe 4wd which has a Eaton locking rear end, it locks when a slight amt of wheel slippage is detected and i find it works very well. It appears the locking system on the 4runner is electronic but it does not come on the Limited, it is a feature of the Trail. Will my limited have an inferior 4wd system to my tahoe's 4wd by cirtue of not having the rear locker? Im sure it will be fine either way but i navigate mud, water and deep slippery mudruts in Florida.
Your Tahoe probably had a g80 rear in it. They work fine when used properly (as a low speed traction device), but they can have a slight delay before lock (100rpm slip is required). It is a purely mechanical auto locker system. Note: this only works on the rear drive. The front was most likely an open diff.
The limited T4R will have open diffs front and rear. However, if you are in 4LO you can activate the electronic traction control system called ATRAC. ATRAC works both front and rear. When it detects one wheels speed being greater than the other on a given axle, it uses the ABS system to apply some brake to the higher speed wheel so that power is distributed to the other. It works surprisingly well. Its not quite as good as being mechanically locked, but it works pretty darn good. Since it is front and rear it should provide you with more capability to keep moving than the Tahoe. It does heat the brakes a bit. so I'm not sure how effective it is in deep extended mud sections. It works great in rock crawling or most typical low speed offroading situations.
Even though my 4runner has selectable mechanical lockers front and rear, I often still use ATRAC. It has the advantage of keeping the vehicle from crabbing from side to side in extremely slick off camber situations. Both wheels spinning with a really low friction coefficient will cause the vehicle to walk side to side looking for traction (this can be very bad in tight situations)..... The ATRAC can still cause the same effect, but since it is not a fixed linked between the axles, the crabbing is greatly reduced. Another advantage of ATRAC is that steering is not degraded.
Mechanical lockers are still better for many situations, but ATRAC is almost always good enough to keep you moving. It's just not always graceful or super smooth.
Overall, I think you will be quite happy with the offroad traction when in 4LO with ATRAC engaged.
Don't listen to the Chevy haters here... We are not all that close minded I own both brands and have worked on all types of Chevys. They each have their strengths and weaknesses.
Here is a goofy Toyota video explaining how to use ATRAC. (they target a rather clueless demographic)
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