2017~2024 Rear Drive Engaged?

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2020 CX-5 Signature Azul Metalico
Regarding incline at what point/percent grade is rear drive engaged? Also is it progressive and if so at what point is it fully engaged?
 
It's not a simple on/off based on a single parameter such as incline. Per Mazda: The MAZDA intelligent system uses 27 distinct inputs and also alters the intelligent steering system to adjust the control parameters up to 200 times per second. So in summary, it's constantly performing calculations based on those 27 inputs to adjust the drive system.
 
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Thank you. Yes that's a nice outline of Mazda's overall system. My question was directed at the systems response to hill/incline and delivery of drive to the rear axel. One of the parameters that the car's intelligent system responds to is hill incline angle so I was asking about that.
 
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Thank you. Yes that's a nice outline of Mazda's overall system. My question was directed at the systems response to hill/incline and delivery of drive to the rear axel. One of the parameters that the car's intelligent system responds to is hill incline angle so I was asking about that.

I think you'd need to speak to a Mazda engineer to get a specific answer to the question you're asking.
 
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According to MAZDA my 2021 GTR has all four wheels engaged always. Power is transferred back and forth based on sensor input.
 
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I think you’re thinking of it too hard. It isn’t necessarily linked to incline it’s linked to demand. You could cruise up quite a steep incline with it barely engaged on a light throttle. Conversely, if you accelerate down a steepish incline it could be fully engaged. Think of it as being linked to the gas pedal with influences from many other sources to bring it in more or in the case of heavy cornering it might back it off. It’s a “smart” infinitely variable coupling.
 
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Nice video with a bit of new information for me. Interesting that it sends drive to the rear during acceleration. Wish that would alleviate torque steer. Think I'll use the music to meditate by...well if I meditated...
 
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The other day I was driving up my steep back entrance dirt road and found my self pretty well blocked at the top by a parked vehicle visiting a neighbor. I thought maybe I could squeeze by just barely while avoiding scratching the car with the heavy shrubbery on the other side. I almost made it past but then three wheels started to spin, two front and one rear. I tried turning off the TCS but still no drive to the one rear wheel on the driest part of the road surface. Ended up having to back down all the way on a narrow steep stretch. This reminded me of many, many years ago when I had a '74 Ford F 250 4x4 with the Full-time Four wheel Drive transfer case. As long as you were on a surface where all wheels had similar traction i.e. snow, sand, mud you had four wheel drive but if you parked with one wheel on an ice patch and the others on dry pavement all drive would go to the wheel on the ice patch. Wish Mazda could use it's "jimba-ittai" to send drive traction to the wheel with traction when the others don't have it as in the above example.
 
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The other day I was driving up my steep back entrance dirt road and found my self pretty well blocked at the top by a parked vehicle visiting a neighbor. I thought maybe I could squeeze by just barely while avoiding scratching the car with the heavy shrubbery on the other side. I almost made it past but then three wheels started to spin, two front and one rear. I tried turning off the TCS but still no drive to the one rear wheel on the driest part of the road surface. Ended up having to back down all the way on a narrow steep stretch. This reminded me of many, many years ago when I had a '74 Ford F 250 4x4 with the Full-time Four wheel Drive transfer case. As long as you were on a surface where all wheels had similar traction i.e. snow, sand, mud you had four wheel drive but if you parked with one wheel on an ice patch and the others on dry pavement all drive would go to the wheel on the ice patch. Wish Mazda could use it's "jimba-ittai" to send drive traction to the wheel with traction when the others don't have it as in the above example.
They’ve improved it a lot with the later models that have an off road mode. It’s a simple device that locks a spinning wheel but at the end of the day, it’s a soft road vehicle and in that respect it’s quite good.
 
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The other day I was driving up my steep back entrance dirt road and found my self pretty well blocked at the top by a parked vehicle visiting a neighbor. I thought maybe I could squeeze by just barely while avoiding scratching the car with the heavy shrubbery on the other side. I almost made it past but then three wheels started to spin, two front and one rear. I tried turning off the TCS but still no drive to the one rear wheel on the driest part of the road surface. Ended up having to back down all the way on a narrow steep stretch. This reminded me of many, many years ago when I had a '74 Ford F 250 4x4 with the Full-time Four wheel Drive transfer case. As long as you were on a surface where all wheels had similar traction i.e. snow, sand, mud you had four wheel drive but if you parked with one wheel on an ice patch and the others on dry pavement all drive would go to the wheel on the ice patch. Wish Mazda could use it's "jimba-ittai" to send drive traction to the wheel with traction when the others don't have it as in the above example.
I assume you mean part-time four wheel drive system in the '74 Ford, aka, you shift the transfer case from 2wd to 4wd, thus connecting both front and rear drive shafts to run at the same speed. In that system, if only 1 wheel was on an ice patch, it would not deliver all the power to that one wheel. Only the power going to that axle (50%) could all go to a single wheel and as long as the other axle (which also got 50% of the power) had traction, you'd be fine. If one or both wheels at both axles had zero traction, then you'd have both those spinning and no drive to the wheel(s) with traction. Usually trucks have a limited slip differential in the rear that will provide some power to the other side when one side starts to slip.

From your description, I'd say the Mazda system was sending power to the rear axle, but that it was simply spinning the tire with no traction. Turning TCS Off (Off Road Traction Assist On) will get some power to the wheel with traction but it can take a few seconds and require a decent application of throttle. What it does is apply increased brake pressure to the spinning wheel and doesn't reduce engine torque so that enough power should get to the wheel with grip. If it's steep and the driest part of the road surface did not have enough grip for the all season tires that are marginally useful off road, then you still might not get enough forward traction anyway.
 
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Thank you. Just to clarify, my 1974 Ford did have Full Time not Part Time 4wd using the New Process 203 (NP203) transfer case. I won't belabor the subject and anyone interested in more information can google it. I could be wrong but I don't think Ford offered Limited slip in those vehicles. So yes the CX-5 is a car with improved traction over a strictly 2wd vehicle and it makes no pretense at being more than that. Understood.
 
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Regarding incline at what point/percent grade is rear drive engaged? Also is it progressive and if so at what point is it fully engaged?
This was a complaint of mine. It is slip-grip. I have a 27% incline driveway, and it didn't fully engage until the front slipped. This is part of what got it traded.

*2019 GTR, tried with wipers on/TC off, all the tricks.
 
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This was a complaint of mine. It is slip-grip. I have a 27% incline driveway, and it didn't fully engage until the front slipped. This is part of what got it traded.

*2019 GTR, tried with wipers on/TC off, all the tricks.
I hope the Rav4 Prime in your signature wasn’t your chosen replacement for that reason. It looks to be as bad or worse than the CX-5 in AWD tests. RAV4 Prime Roller Test
 
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For my open-diffed FWD Protege, I often times wished that I'd have two levers (like a handbrake) to manually brake either the left or right wheels when one of them lost traction in snow.
 
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