Can I safely go down a "tick" in aspect ratio?

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I've been tasked with finding good replacement tires for a family member's late-90s minivan. The tires it takes are P205/75R14. However, unfortunately it seems to be an uncommon tire size these days so there are only a few tires out there to choose from: on TireRack it's either the Hankook Optimo H724 or the Kumho Solus KR21's. Neither of them got very good reviews.

Walmart carries the Goodyear Viva 2 tires, and they're priced well and I feel more comfortable buying the Goodyear brand, but the reviews I'm seeing for them aren't very good either.

However, if I go up/down in the width and/or aspect ratio a bit, there are way better tires to choose from; for example by going down 5 in the aspect ratio from 205/75/14 to 205/70/14 I can get the relatively highly regarded Michelin Defender tires. And by going down both 10 in the width and 5 in the aspect ratio to 195/70R14, the General AltiMAX RT43 tires, also relatively highly regarded, become available as a choice.

So my question is, how safe is it to go with a slightly different width and/or aspect ratio and if it is safe, what would be the max I should deviate from the OEM tire size of 205/75/14? If it's not safe or recommended, can anyone recommend good tires for that OEM size?
 
Originally Posted By: cantthinkofaname
So my question is, how safe is it to go with a slightly different width and/or aspect ratio

Not really safe because a lower aspect ratio will have a lower load rating which is going to be below what the car manufacturer has envisioned for your vehicle.

Also, most shops nowadays will refuse to install such tires on your vehicle.

What specific vehicle (year, make, model, version) are we talking about here?
 
I'd take the Kumho's. The KR21's get a bad rap for not meeting rated mileage. I think otherwise they are a fine tire.

In a minivan I would be hesitant to choose a smaller tire in width or aspect ratio. Minivan's usually push it for load capacity, and then the owners take that even further.

So assuming you can go up 10mm in width, or perhaps even 20mm in width that would be "safe" if it doesn't rub anything.

But on someone else car, no way I would recommend a smaller tire. I'd recommend the KR21's.
 
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Originally Posted By: cantthinkofaname
Walmart carries the Goodyear Viva 2 tires, and they're priced well and I feel more comfortable buying the Goodyear brand, but the reviews I'm seeing for them aren't very good either.


You're right, they aren't good. My brother had a set on his car. Tire had lots of tread left, but they developed broken belts, causing a sound like broken wheel bearings. Would have been a matter of time before they failed catastrophically. Apparently quite a common problem on the Viva 2 tire.

Originally Posted By: cantthinkofaname

However, if I go up/down in the width and/or aspect ratio a bit, there are way better tires to choose from; for example by going down 5 in the aspect ratio from 205/75/14 to 205/70/14 I can get the relatively highly regarded Michelin Defender tires. And by going down both 10 in the width and 5 in the aspect ratio to 195/70R14, the General AltiMAX RT43 tires, also relatively highly regarded, become available as a choice.

So my question is, how safe is it to go with a slightly different width and/or aspect ratio and if it is safe, what would be the max I should deviate from the OEM tire size of 205/75/14? If it's not safe or recommended, can anyone recommend good tires for that OEM size?


Staying with the correct overall size means going to 215/70R14 or 225/70R14. Selection isn't much better there, either. 14" tires are being abandoned by tire companies. A better idea may be to replace the wheels with 15" (cheap used steel ones can likely be had). The equivalent size there is 215/65R15, and choices are much better in that size. Be sure the load index of whatever is chosen is at least that of what was originally installed.
 
Originally Posted By: weebl
A better idea may be to replace the wheels with 15" (cheap used steel ones can likely be had). The equivalent size there is 215/65R15, and choices are much better in that size. Be sure the load index of whatever is chosen is at least that of what was originally installed.

This would be my advice as well. But if that's too much trouble, then just stick with the Kumho in OEM size. Another tire that you could look at in OEM size is Toyo Extensa A/S.
 
Originally Posted By: bepperb
I'd take the Kumho's. The KR21's get a bad rap for not meeting rated mileage. I think otherwise they are a fine tire.

In a minivan I would be hesitant to choose a smaller tire in width or aspect ratio. Minivan's usually push it for load capacity, and then the owners take that even further.

So assuming you can go up 10mm in width, or perhaps even 20mm in width that would be "safe" if it doesn't rub anything.

But on someone else car, no way I would recommend a smaller tire. I'd recommend the KR21's.

Thanks. One thing I am seeing for the KR21's is also complaints about performance in wet conditions. One or two recent reviewers seemed to suggest that the tires used to be better in wet conditions but Kumho recently made a slight design change to the tire which resulted in inferior performance. Whether or not this is true, I don't know.

Regarding load capacity, I will say that they don't ever carry anything heavy in the vehicle. But yeah, I didn't think about that. It looks like the load capacity of the lower-aspect-ratio Defenders is 600 pounds less (5424) than the correctly sized KR21s. But the curb weight for the van is about 3700lbs. max. Factor in 800 pounds of passengers (even though it would always be much less) and that brings it up to 4500lbs, still 1000lbs. under the tires' load capacity.
 
Originally Posted By: cantthinkofaname
It looks like the load capacity of the lower-aspect-ratio Defenders is 600 pounds less (5424) than the correctly sized KR21s. But the curb weight for the van is about 3700lbs. max. Factor in 800 pounds of passengers (even though it would always be much less) and that brings it up to 4500lbs, still 1000lbs. under the tires' load capacity.

You're talking about static load. But when the vehicle is in motion, making turns, accelerating, braking, the load on each individual tire will fluctuate quite a bit.
 
Originally Posted By: cantthinkofaname
Regarding load capacity, I will say that they don't ever carry anything heavy in the vehicle. But yeah, I didn't think about that. It looks like the load capacity of the lower-aspect-ratio Defenders is 600 pounds less (5424) than the correctly sized KR21s. But the curb weight for the van is about 3700lbs. max. Factor in 800 pounds of passengers (even though it would always be much less) and that brings it up to 4500lbs, still 1000lbs. under the tires' load capacity.


There will be a load index for the smallest OEM tire ever equipped on that vehicle. That is what your minimum should be. Being a 1997 vehicle, it may or may not have been indicated on the tire placard, but a tire website should be able to tell you. It will consist of a two or three digit number, followed by a letter. Most likely, I think you will see it is the following: 215/75R14 95S

So 95 should be the minimum load index in this case, and S should be the lowest speed rating (unless we are talking winter tires). For all-seasons in this size, you're likely to only find S or T, so likely all will be fine.
 
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I think your best options are either just getting the Kumho in the correct size or as other posters have mentioned, getting some cheap 15" wheels and then either tires in 215/65/15 or even 205/70/15.
 
We have KR21's on a 2011 Subaru Outback, for two years. No wet or snow traction issues at all. Only complaint will be that the tires won't really go 60K miles, but I priced them to go 45K as break even, and they will go at least that far.
 
I have a set of Hankook H724 on my 1990 F150, I actually like them. I get good traction in wet weather. I prefer a "car" tire on this truck because it rides better. I think I will actually get 50,000 miles out these tires, something I cannot say for most of the tires I have bought.
 
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Stay with the standard sizes, or go to 15 inch wheels. I think most tyre reviews need to be taken with a grain of salt. And it's a minivan after all, not going to be driven on too many qualifying laps (I'd hope!)
 
Here is the formula for determining the outer diameter of a tire:

Using the OP's 205/75/14 tire

205X75% = 153.75
convert to inches by dividing by 25.4 (which is constant) = 6.053 X2= 12.106 + the diameter of the tire (14)= 26.106

Any upgrade should equal this + or - 1/2 inch.

In other words a 215/70/14 = 25.85 OD and is within 1/2 inch
a 225/70/14 = 26.40 and would work too.
 
Originally Posted By: JayhawkRoy
We have KR21's on a 2011 Subaru Outback, for two years. No wet or snow traction issues at all. Only complaint will be that the tires won't really go 60K miles, but I priced them to go 45K as break even, and they will go at least that far.


Thanks. 4WD/AWD I assume? Do you remember when you bought the tires? (I know someone in a review mentioned the design changed recently for the worse, at least with regards to wet traction.)
 
Originally Posted By: Quattro Pete
Originally Posted By: weebl
A better idea may be to replace the wheels with 15" (cheap used steel ones can likely be had). The equivalent size there is 215/65R15, and choices are much better in that size. Be sure the load index of whatever is chosen is at least that of what was originally installed.

This would be my advice as well. But if that's too much trouble, then just stick with the Kumho in OEM size. Another tire that you could look at in OEM size is Toyo Extensa A/S.


Thanks to both of you guys. I ran it across the family member and they're not interested in buying a new set of wheels. Never heard of the Toyo Extensa A/S's, so unfortunately there are fewer reviews to read, however the fact that they've got a 45 day / 500 mile money day back guarantee is pretty nice and appealing.
 
Originally Posted By: stephen9666
I would probably just stick with the OE size. Either the KR21 or H724 would probably be fine for a sensible driver.

As far as the KR21 wet traction, CR rates it "good" in that category, and Tire Rack seems to have a somewhat similar rating.

Here's the Tire Rack test that included the KR21:
http://www.tirerack.com/tires/tests/chartDisplay.jsp?ttid=96

Thanks, I saw the TR test but am unable to see CR's ratings. Seeing that you've got access to CR's ratings... do you see any of the tires mentioned here there that are rated higher in CR than the KR21's by any chance?
 
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