A Few Surprises from US 2018 Mazda CX-5

2018 CX-5 GT has memory seat and power passenger seat standard, and for me I have no reason to get GT Premium Package for $1,385 as I don’t really need those features for cold weather and not interested to have Mazda Active Driving Display.


Also talked to the GM Alex and complaining about cylinder deactivation.

Great info, thanks! I agree that no need to spend extra for something that's now standard, auto-memory seats was a requirement for the 2 different drivers. Heated rear seats & steering wheel are nice but not worth the extra $$$.

What's the beef with cylinder deactivation?
 
⋯ What's the beef with cylinder deactivation?
Whats wrong with cylinder deactivation?
Cylinder deactivation has been tried and failed by many car manufactures beginning with GM in 80s. Currently Honda V6 VCM is the only engine other than Mazda SA-G implementing cylinder deactivation in the US and it has been suffered class action lawsuit due to spark plug fouling and oil consumptions. I dont see any new technology been implemented by Mazda to address these issues with cylinder deactivation, and I dont want take any risk as a guinea pig just to save almost nothing MPG.


When you produce the same power with half the cylinders and half the displacement, you gain efficiency through a reduction in pumping losses. The reduction comes from pumping half the cylinder volume, and from a reduction in intake head loss due to the throttle being more open. Under the light load conditions when cylinders are deactivated, the turbo is practically doing nothing, so I think you would get roughly the same efficiency boost from cylinder deactivation regardless of whether there is a turbo.

Regarding whether owners will notice, that isn't the concern. The reason why cylinder deactivation has a bad reputation is the oil fouling issues that appear as the miles accumulate, resulting in misfires or worse. We won't be able to judge whether Mazda has solved these problems for a few years.
Except that the hydraulic lifters that collapse under de-activation sometimes get stuck. Old or dirty oil, things like that. Valves get gummed up with PCV crap that accumulates on them when they're not open. Piston rings get shot because the crap goes down the cylinder at activation, so you get oil consumption out of nowhere...
Unless they do things differently, but I think they don't.

If Mazda has found a way nobody else could to resolve common issues from cylinder deactivation, it will say it. Instead Mazda only mentioned the vibration issue using a fulcrum inside the SkyActiv-Drive transmission to help seamless transition between two- and four-cylinder operation. The key point still is cylinder deactivation is not effective enough to save 2 MPG like someone else estimated before, but keeps the same 26 MPG combined on EPA rating for AWD CX-5. This further proves the cylinder deactivation is not effective to save fuel, but carries ill side-effects in the long run.

You definitely made a right decision by going for a 2017 CX-5 with better price and not to worry about the unknown of cylinder deactivation only for slight or no MPG gains.

Yeah cylinder deactivation is built in to the engine operation like turbo charger. Drivers cant intervene it and for Honda V6 VCM cylinder deactivation many owners use VCMuzzler or KTuner to disable it.

Honda has gone through class action lawsuit with its VCM problems found on 2008~2013 V6s due to spark plug fouling and oil consumption, in addition to early engine mount and position ring failures caused by engine misfiring. Honda claimed the newer generation of V6 VCM has many updates including dumped tri-mode cylinder deactivation with 6-4-3 to dual-mode 6-3 cylinders; altered VCM software to turn the VCM on/off more frequently reducing heat/cool cycles of piston temperature which should prevent oil consumption; upgraded piston rings and engine mounts helping to prevent engine oil consumption and vibration.

Mazda might have done a better job than Honda this time for cylinder deactivation, but consider thiss the first for an I4 so why risk it for very minimum MPG gain?

Its a long term reliability issue, not if you notice it or not. For 1 MPG gain on CX-5 FWD or no gain on an AWD, its not worth the risk.
 
How about 16? [emoji4]
These 2 types of vents will be interchangeable perfectly. The problem for the 1st-gen CX-5 is the parts wont be available in the US; whereas for the 2nd-gen CX-5 you can special order the parts easily from any US Mazda dealers.
 
I hear ya, but it doesn't seem that Mazda would shoot itself in the foot to shave off 1mpg, and I agree that if it's only 1 MPG, why bother at all.
 
These 2 types of vents will be interchangeable perfectly. The problem for the 1st-gen CX-5 is the parts won’t be available in the US; whereas for the 2nd-gen CX-5 you can special order the parts easily from any US Mazda dealers.

I'm assuming 7's post was in jest. Gen 1 has different vents than the Gen 2.
 
Wonder if we Aussies will get "dial open/close controls on center dash vents" in April/May of this year (uhm)
 
I hear ya, but it doesn't seem that Mazda would shoot itself in the foot to shave off 1mpg, and I agree that if it's only 1 MPG, why bother at all.

A 1 MPG improvement on their largest selling vehicle (by a wide margin) could be a big deal in today's world of slowly tightening CAFE standards. I don't know how much wiggle room Mazda has against the fuel economy requirements, but given that they don't market any hybrid vehicles it's possible they need all the help they can get. It also brings the EPA highway rating for the AWD model up to the magic number 30 which might catch a few buyers' eyes.
 
A 1 MPG improvement on their largest selling vehicle (by a wide margin) could be a big deal in today's world of slowly tightening CAFE standards. I don't know how much wiggle room Mazda has against the fuel economy requirements, but given that they don't market any hybrid vehicles it's possible they need all the help they can get. It also brings the EPA highway rating for the AWD model up to the magic number 30 which might catch a few buyers' eyes.

This is the last throw of the dice for these current engines until SkyActiv-X comes online
 
What’s the downside to cylinder deactivation?



Is this throwing fuel on the discussion or a real question?

There is no downside other than some may prefer simpler engine technology. If I have the choice between having it or not I would not have it. Same with turbos. I don’t need them. But if the car has it already then that is that. It’s not a dealbreaker for me.

Everyone has their dealbreaker point.
 
I guess my point is if it does no harm, which is probably the case, no big deal. As long as they did a good job engineering. A lot of stuff people used to say was too complicated like fuel injection and electronic ignition.... totally reliable.
 
But on diesel he truely believe MNAO is pushing it hard evidenced by MNAO has scheduled training courses on diesel for his technicians. So there's still some hope for diesel lovers. :)

Oh great, I am now well into my evaluation of alternatives for a diesel Mazda and now a glimmer of hope is dangled in front of my eyes. Cruel.
 
Whats the downside to cylinder deactivation?


From what people have said, on this forum and others, is that in the long run, you have issues. Not in the first year or two but in years 4+. Burning oil, etc.
 
I don't agree that it is. This tech isn't that new. Honda Odyssey had it in 2010.
Of course I M the forum optimist apparently.
And still no sign of 18s on the official Mazda site. So sketchy....
 
They don't want people looking for deals on the 17s yet because they have too much inventory, I'd bet.
 
They don't want people looking for deals on the 17s yet because they have too much inventory, I'd bet.

Could be but since 2018 is now on sale, they should be listing it on their website if for no other reason than keeping up with the various requirements to list this type of information (if any requirements exist that is!)
 
I don't agree that it is. This tech isn't that new. Honda Odyssey had it in 2010.
Of course I M the forum optimist apparently.
And still no sign of 18s on the official Mazda site. So sketchy....
Yes cylinder deactivation is not new but many had tried and failed. The rotary engine is not new either and why can Mazda just bring it back?

Honda has gone through class-action lawsuit with its VCM problems found on 2008~2013 V6s, including the Odyssey you mentioned, due to spark plug fouling and oil consumption, in addition to early engine mount and position ring failures caused by engine misfiring. Honda has to pay for all the repairs related to cylinder deactivation based on the settlement of class-action lawsuit.
 
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