Subaru or Mazda?

[Jimmy_Russells]

Nevertheless, I call it bad engineering, no matter what manufacturer.

Bad engineering how? Something written in a manual ages ago, as a precaution/recommendation (which was likely just to boost tire sales at the dealer), with no supporting failed differentials in decades since is hardly bad engineering.

Certainly there have been millions of combinations of the things Subaru warned against and yet there’s no evidence anywhere that this has caused failures, makes your position more ludicrous than the LSPI boogeyman. Lots of hype, not much objective evidence it’s as destructive as claimed.

And yes, I’ll use other, lesser AWD vehicles as examples that the caution only truly applies if you have different size ODs (26” vs 28” ex.); tire size that started with same overall height, worn from driving or misalignment are never going to damage the differential systems.

But it does exactly that, compensate by locking the diffs. Too long of a lock and it burns up, especially when only partially locked.

Sounds like redbone just doesn't understand how these systems actually work. As stated, a different tire diameter is causing the system to believe either that one tire, or the other three tires (depending on if the tire diamter is smaller, or larger than the others) is slipping. So of course the system is going to try and correct that, that is the entire point.

I can't think of any vehicle on the road today that doesn't at least have a brake activation traction control system to stop a slipping wheel and send power to the other wheel that does have grip. This has been a regular system on vehicles now for at least 15 years. Even on a 2wd vehicle with an open diff if you run different tire sizes side to side on the same axle without deactivating the traction control, you're going to have driveability issues.

 

[alarmguy]

Skyactiv GDI has been out long enough that if carbon buildup is an issue, the Mazda forums would be moaning about it by now.

dunno about Sub.

Skyactive is an amazing engine. We have a Mazda 3 Skyactive 2012, runs perfect (only 97k miles though) Never needed a repair, did I say NEVER NEEDED A REPAIR and to this day engine as dry as a bone, no seepage of any kind. Runs as good as the day we bought it.

Literally just replaced the Mazda two days ago with a 2025 Chevy Equinox and was confident enough to sell the Mazda to a member of our community. The Mazda 3 is not a long distance machine do to the seating but it was a blast to drive all around town and even highways just not hours at a time. I considered a 5 and 50 but ran into the redesigned 2025 Equinox and wife wanted it. We also considered a VW Tiguan and actually thought we would buy one until the Equinox

 

[duck__dodgers]

a used 2022 Hyundai Kona 2.0 N/A with 28k miles. ....have avoided H/K products right now due to their engine self destruction tendencies but I’m hoping for her sake they were solved by 2022. I see that the 2022 Kona has a CVT so I’ll try to encourage a fluid change. Do these require Hyundai brand CVT fluid or would Valvoline, Castro etc….suffice?

PS: I realize the Kona is smaller than either the Forester or CX-5 but she picked it so she must have found it big enough…

Supposedly per the internet (take with salt), H/K engines react poorly to long engine oil intervals when the mileage >80,000. Whereas, (as a random example), you don't hear the same sorts of issues w/high-mileage Skyactiv, even w/the cylinder deactivation----even though it's a certainty that there are lots of neglectful Mazda owners just like any brand..

So at the min., stick w/the severe service oil change interval if you plan on keeping that car for the long haul.

Good luck!

 

[pbm]

Supposedly per the internet (take with salt), H/K engines react poorly to long engine oil intervals when the mileage >80,000. Whereas, (as a random example), you don't hear the same sorts of issues w/high-mileage Skyactiv, even w/the cylinder deactivation----even though it's a certainty that there are lots of neglectful Mazda owners just like any brand..

So at the min., stick w/the severe service oil change interval if you plan on keeping that car for the long haul.

Good luck!

I agree with you but as I stated in the OP it’s a family member (niece) who bought this Kona not me. I’ll advise her (and even perform the maintenance for her) but ultimately it’s up to her. I do notice the H/K court ordered engine warranty ended with MY 2020 so it’s possible the problems won’t show up on a 2022.

 

[redbone3]

If the diff locks with such a small difference in rotational speed, what happens on a long curve?? Subaru doesn't claim you have to only drive on straight roads. A diff that can't deal with tires that are different because one is worn more than the other has a design problem.

 

[tcp71]

Have a 2009 subaru tribeca my mother (81yo) drives and a 2013 FWD CX-5 my youngest son drives. both are good vehicles. The tribeca with winter tires is a tank, but it still has one of the actual "symetrical" awd systems.

I like the Macan system. You can display the torque split in the gauge cluster. Add in rear axle torque vectoring and it's great fun.

 

[Silverado12]

Of those two I would pick the Subaru all day any day. Mazda isn't all that IMO. My brother's wife has a Forester and it's comfy to ride in. A friend of mine has a CX5 and I'm not impressed at all.

 

[bobdoo]

Of those two I would pick the Subaru all day any day. Mazda isn't all that IMO. My brother's wife has a Forester and it's comfy to ride in. A friend of mine has a CX5 and I'm not impressed at all.

Wife just went from an Outback, to a CX-5. The new Outback rode worse, and was much noisier. The supercomputer infotainment is a joke for using while moving. The Forester rode even worse, and was noisier. Wife LOVED her 2012 Outback.

I tried to get her to buy a RAV4 hybrid, but she insisted that the CX-5 was better.

I've owned a 2000 Outback, 2012 Impreza, and now my 2016 CX-5. The Mazda has much more intelligent design. As far as AWD in ice, it is NOT as good as a vehicle with a Locking Rear Diff. The Outback, Forester, and Impreza variation don't have locking rear diffs, either.

Actual real-world driving will be practically identical, as far as traction goes, with the spinning wheels being coarsely brake-checked into submission.

 

[Pew]

If the diff locks with such a small difference in rotational speed, what happens on a long curve?? Subaru doesn't claim you have to only drive on straight roads. A diff that can't deal with tires that are different because one is worn more than the other has a design problem.

On a long enough curve at a different enough speed the diffs will start to lock. But turns aren't forever either and when the road goes straight again is when the LSD will get a rest. Go fast enough for long enough and it will still burn. Good old active AWD systems (like the mitsu SAWC) and most newer AWD systems will have the center and/or front and rear LSD if equipped lock or unlock based off an algorithm of wheel speed, throttle, steering angle, and g forces.

I've overheated the rear diff/LSD/AWD pump on the Evo quite a few times but it takes alot - like really bad tires on a track sliding around everywhere for 6 20 minute sessions but it's absolutely fun doing AWD donuts.

 

[Glenda W.]

Nope, it is gone with the new cover design. I have a photo with the car on the lift in the hot rod shop but it was a low-res phone photo.

Might be able to do and extraction for a partial drain and fill. I am not inclined to remove the cover to drain it. magnetic plug to the rescue. Frustrating. Thanks Subaru.

What year is your vehicle? 2018 outback? That may be a diff diff. Up front, my wife has a 6 speed MT which I think is a shared lube sump, so that special juice will stay till 60K. Just waiting for balky shifts when they use the incorrect lube. Death by bulk gear oil.

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Here’s my friends 2024 Crosstrek that he just bought.