Only issue I have found with 4A, and I don't know if it's a problem with my truck, or just a function of the clutch based transfer case. I have had a few, pretty much count on one hand, instances where I pulled out and gunned it and the truck revved like crazy but was accelerating like a '93 Civic. I noticed after the first time that my traction control light was flashing. I know none of the tires were spinning, so it makes me think it's spinning the transfer case clutch and traction control is kicking in and cutting power.

I know that the Limited and Raptor have a lock up transfer case for 4A, but I thought that would only come into play if rock crawling in 4 Low. I wonder if the PB is actually overpowering the clutch in some instances, or if I have a problem. Truck doesn't throw any codes or drive poorly when I let off. Again, it's a rare thing. I don't typically full throttle the truck, and most of the time if I do it reacts just fine, especially off a straight line start. It's only when turning and then accelerating hard.

 

Sounds like a sensor is a little wonky and pulling power because of it's reading. For sure not normal as I do rocket launches, as my kids call it, every one in a while for our enjoyment and it takes off like crazy.

 

On a Powerboost, there is likely to be a larger difference in 2H vs 4A fuel economy. When the truck is in 4A, regenerative braking has a delay before engaging. In 2H, there is no delay. I think the delay is due to regenerative braking potentially interfering with traction control and ABS function in slippery conditions. Less regen braking means less battery charge and less assistance from the electric motor.

 

my 2022 runs in 4a over 90% of the time and i have 3.31 gears no axle iwe
its gets 18.7 around town and might jump to 19 at 75 on highway
in 2h its pretty much the same...as i cant find any difference in mpg or noise in cabin

 

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When a tire spins (even one rear tire) the traction control shift schedule engages and delays the shifts while revving the snot out of it. It’s disconcerting….but one tap of the TC button prevents that. The eco (and my supercharged truck) have plenty of torque and when making a tight tune and getting in it, it does as you describe occasionally.

When the cases do slip, full boost launch from rest, it feels like wheelhop, and isn’t overly pleasant. Otherwise, the non-locking TOD case virtually never slips.

hope that helps.

 

That helps a lot, I suspect it's still lifting a wheel a bit since it only seems to be after turning. What you say makes a lot of sense, I guess I expected in 4A the truck would just accept that slippage is possible and the front will get things moving.

 

Unless it's snowing and wet slushy roads, or mud covered, stop driving in 4A.

 

No.

 

No x 2

 

About the only time 4A is a problem is when you're on dry pavement, you are doing a tight turn, and you apply LOTS of power. This will make the TOD clutch pack apply close to 100%. This results in the front and rear drivelines being in a state similar to 4H and the TC won't tolerate much slip between front and rear drivelines and you get lots of heat and wear and driveline binding. That's about the only significant limitation of the 4A system that I've seen. Drive with that limitation in mind and 4A all the time won't hurt anything much, if at all.