[imaginarydave]

I've been reading up on efficiency loss with wheel/tire choices. my AWD/limited arrives in about a month and I am starting to plan. my bigger concern is winter driving range come ski season.

Best I can tell rolling resistance of the tires is issue number one, followed by wheel size. how important is the aero qualities of the rims though? There doesnt seem to be many aero focused after market wheels marketted other than for teslas.

Would I be good just buying any decent looking 18" rims (even second hand) that fit and putting x-ice tires on it come winter?

 

[Whale2222]

I've been reading up on efficiency loss with wheel/tire choices. my AWD/limited arrives in about a month and I am starting to plan. my bigger concern is winter driving range come ski season.

Best I can tell rolling resistance of the tires is issue number one, followed by wheel size. how important is the aero qualities of the rims though? There doesnt seem to be many aero focused after market wheels marketted other than for teslas.

Would I be good just buying any decent looking 18" rims (even second hand) that fit and putting x-ice tires on it come winter?

I am interested in this too. I wonder how many miles would be lost using regular wheels instead of the aero wheels that come with the car. Regular wheels are so easy to find that I am tempted to try them out. What could I lose, 10 or 15 miles of range?

 

[curiousmike]

Seeing as I just had to replace a rear tire due to a sidewall nail ( 1200 miles on my new car ) and the only tire I could get was the "normal" Michelin Primacy 235/55/19, I'm also interested in how bad I screwed up.

What did I just give up putting a "normal" tire on the rear?

 

[Tonys_I5]

I am interested in this too. I wonder how many miles would be lost using regular wheels instead of the aero wheels that come with the car. Regular wheels are so easy to find that I am tempted to try them out. What could I lose, 10 or 15 miles of range?

When I changed the wheels/tires on my Mach-E back in the day, I saw a 10% reduction but that was driving 90% on the freeway. Much lighter wheels, too, but normal tires that were wider and not as efficient. Went from 19" to 20" wheels as well. There are a few different "low rolling resistant" eco tires that you can find on tirerack, just to get an idea of how many are out there. Honestly, the additional price you pay for those special tires will most likely not pay themselves off in fueling/charging costs but it never hurts to calculate the difference.

 

[Nitespirit]

Seeing as I just had to replace a rear tire due to a sidewall nail ( 1200 miles on my new car ) and the only tire I could get was the "normal" Michelin Primacy 235/55/19, I'm also interested in how bad I screwed up.

What did I just give up putting a "normal" tire on the rear?

I had a side wall blow out too - - damn potholes. I ended up having to replace with the same Primacy tires. Yes, I bought 2 so that the rear tires match. I keep the other good one for future use.

 

[Fan of EV]

I had a side wall blow out too - - damn potholes. I ended up having to replace with the same Primacy tires. Yes, I bought 2 so that the rear tires match. I keep the other good one for future use.

Good move.

A bad pothole on a LA freeway took out a tire on my old car. That car, like the Ioniq 5, did not have a spare tire just a can of sealant and a pump which does no good for a blown out sidewall. The tire shop local to the incident did not have matching tires so I bought 2 so both on the axle would match. My mistake was in not retaining possession of the good tire.

A couple of months later and I got a screw in the side wall of one of the other original tires. That resulted in two more tires being purchased for the other axle.

Had I retained the good tire from the first incident then it would have been a simple matter to use it to replace the one with the screw in the sidewall at a considerable savings.

 

[Lowellt]

I am interested in this too. I wonder how many miles would be lost using regular wheels instead of the aero wheels that come with the car. Regular wheels are so easy to find that I am tempted to try them out. What could I lose, 10 or 15 miles of range?

I too have started to look for a more easily available set of tires for my limited. Last Thursday, I had a sidewall blow out on my rear passenger side tire. I had it towed to a nearby dealer, and they tell me it will take a couple of weeks to find one. There is not a single one to be found in Washington state.

Not too terrible, but it has me concerned about how this happened when I was driving at about 5 mph when I heard it blow. If I’m on a road trip, this would be a problematic. I do understand that a michelin sport pilot would work, but it’s 2k+ for 4 of them, so I’m mulling it over.

 

[anthoj]

According to this video, impact on efficiency goes like:

1. Wheels size - most impact, 2 inches affects efficiency as high as 15%
2. Rolling resistance - some impact, but realistically if you choose a set of decent tires, it's not going to affect you too much, probably around 3-5% or less.
3. Tire width - this has the least amount of impact on efficiency. Increasing your tire width by 50% reduces your efficiency by only 1-1.5%.

As for aero design, there are many factors but based on several youtube video tests I've seen, it looks to be anywhere between a 2-5% difference in efficiency.

I would say, if you go down 1 wheel size, you can mitigate (or at least minimize) most, if not all the losses from the wheel design, non-ev tires and tire width. Going down 2 wheel sizes should still increase your efficiency despite all the other factors. I was reading somewhere 17" might be too small for the brake rotors, so 18" is your best bet.

 

[Nitespirit]

I too have started to look for a more easily available set of tires for my limited. Last Thursday, I had a sidewall blow out on my rear passenger side tire. I had it towed to a nearby dealer, and they tell me it will take a couple of weeks to find one. There is not a single one to be found in Washington state.

Not too terrible, but it has me concerned about how this happened when I was driving at about 5 mph when I heard it blow. If I’m on a road trip, this would be a problematic. I do understand that a michelin sport pilot would work, but it’s 2k+ for 4 of them, so I’m mulling it over.

you only need 2, not 4. Try the Michelin Primacy. Almost identical except it does not have the foam inside, which is to lessen the road noise. I did not notice any difference in the sound levels.

 

[ElFroCampeador]

On the I5, numbers posted around suggest the range differential 19 vs 20" (stock) is about 5%. Nobody has studied exactly what causes that for these specific tires, but it's probably mostly drag related (the 20" wheels are... bigger. And also wider, and therefore present a significantly larger face to the airstream. Engineering Explained on youtube did a fairly detailed video on tire size a while back). Call it 10-15 miles. There have been some people talking about 18" wheels, don't know if they've reported any numbers, but assuming the effect is linear, you might expect another couple/few percent improvement (though the car might look a touch goofy )

 

[anthoj]

you only need 2, not 4. Try the Michelin Primacy. Almost identical except it does not have the foam inside, which is to lessen the road noise. I did not notice any difference in the sound levels.

My understanding is you should never mix and match tires, especially if they have different tread patterns. Is this not true?

 

[Lowellt]

My understanding is you should never mix and match tires, especially if they have different tread patterns. Is this not true?

That’s what I was told.

 

[GrantL]

My understanding is you should never mix and match tires, especially if they have different tread patterns. Is this not true?

It is true because different tread will give different resistance, grip and stopping distance. This will give strain to mostly AWD drive train and the differential coupling thus more wear and tear on these expensive parts.

 

[TimW]

On the I5, numbers posted around suggest the range differential 19 vs 20" (stock) is about 5%.

For the North American tyres (different tyres to other markets) the difference between 19" and 20" wheels is 2% on the highway cycle and 5-6% on the city cycle. They used exactly the same car to do the EPA testing of the AWD with both wheels.

For the Korean/Euro wheels and tyres the majority of the difference comes from different tyre types, with a 15% difference in rolling resistance because they chose to prioritise performance on the 20".

Everyone cites that engineering explained video, but it is flawed because there are multiple differences between the different wheels compared - different tyre type and different wheel design.

 

[ElFroCampeador]

For the North American tyres (different tyres to other markets) the difference between 19" and 20" wheels is 2% on the highway cycle and 5-6% on the city cycle. They used exactly the same car to do the EPA testing of the AWD with both wheels.

For the Korean/Euro wheels and tyres the majority of the difference comes from different tyre types, with a 15% difference in rolling resistance because they chose to prioritise performance on the 20".

Everyone cites that engineering explained video, but it is flawed because there are multiple differences between the different wheels compared - different tyre type and different wheel design.

I wouldn't say flawed so much as incomplete, but that's fair. He was just talking about size, all else being equal. I'd be curious to see numbers on what the effective difference is all factors considered (and how much difference, say, rolling resistance makes relative to drag. I'm guessing it's a bigger deal at lower speeds)

 

[eGuru]

It is true because different tread will give different resistance, grip and stopping distance. This will give strain to mostly AWD drive train and the differential coupling thus more wear and tear on these expensive parts.

There is no "differential coupling" in the I5 AWD as it is dual motor.
The "rule" about matching tires relates to a per axle basis.

 

[eGuru]

Everyone cites that engineering explained video, but it is flawed because there are multiple differences between the different wheels compared - different tyre type and different wheel design.

I would not say it is "flawed" but rather that we need to be aware that the data comparisons we need to look at should be for tire/wheel combinations that have the same diameter. We are not (significantly) changing tire diameter when we select 18", 19", or 20" wheels for our I5s. We are changing the tire aspect ratio.

 

[Pixelated]

It is true because different tread will give different resistance, grip and stopping distance. This will give strain to mostly AWD drive train and the differential coupling thus more wear and tear on these expensive parts.

There is no "differential coupling" in the I5 AWD as it is dual motor.
The "rule" about matching tires relates to a per axle basis.

There is no physical drivetrain connection, front to back, in the AWD setup. Just match per axle.

 

[eGuru]

FWIW

 

[GrantL]

There is no "differential coupling" in the I5 AWD as it is dual motor.
The "rule" about matching tires relates to a per axle basis.

I stand corrected.

Correct me again if wrong, Just a geared differential on each axis for AWD? Maybe to add having different wheels/tires can confuse the computers stability/traction control as well?