Ecopia EP422 tires suck

[Nubo]

I've got an ecopia question for the MNL hivemind....

Reading this thread it seems are getting lousy miles out of the 422s, and others are having no problem. I'm at 4600 miles on a 3 year lease, and have visible wear on the fronts. I'm worried I would make my 30k miles...although I got snows to take some of the miles.

Here's my hypothesis....driving in ECO or 'spirited'. We never drive in ECO (except rarely when we are pushing the range) and push it a bit. Seems to me that in addition to a few more kWh, we will need to replace tires.

Maybe the folks with the long wearing 422s can let us know if they are 100% ECO/hypermilers, or 'spirited'.

I normally drive in eco mode.

But I would note that a lot of folks have a misperception about eco mode. It does not de-tune the car. You can accelerate just as hard, get to 60mph just as quickly, drive just as "spirited" in eco mode as not. Eco changes the shape of the throttle-mapping but does not limit power in any way. I prefer it because I find it gives me finer speed control, not because it "prevents" me from getting full power. It doesn't.

But yes, driving less briskly will preserve the tires. That includes acceleration, deceleration, and how hard you push the car in turns. Road surface is the other factor.

 

[TLeaf]

I'm at 32K and have tons of tread left in the middle of my Ecopias. Shoulder tread, on the other hand, is showing appreciable wear, likely due to my "spirited" driving around corners and freeway cloverleafs. My tires have been rotated 4 times in the past (almost) 4 years, the most recent time by yours truly.

I'm currently debating casting about for a spare set of Ecopias to replace mine when they finally acquire enough nail punctures or enough bald patches on the shoulders to warrant replacement. I've actually come to like the tires, though I admit I should probably be a bit concerned about their willingness to spin freely on damp pavement (then again, I've never had a spin out or problems stopping on our wet Seattle pavement).

 

[DaveinOlyWA]

they seem to wear out too quickly, 30K miles and they are bald on the edges and need to be replaced.

My first set wore on the edges too. Edge wear is indicative of underinflation. I kept the first set at the recommended 36psi but still the tires wore at the edges.

With my second set I am running them at 40 psi. The wear is much more even.

Everytime I take the car to a a dealer or tire shop it comes out with tire pressure set to 32. Most cars are 32 all round and the mechanics don't bother to read the tire information on the drivers door sill. …

After I got my car back from one of the yearly battery checks, I noted the service writer had taken up most of the "notes" section with a GIGANTIC:

checked tire pressure - 44psi
TIRES SHOULD BE 36psi ! ! !

Yes, 3 exclamation points. Seemed to be a very strongly held belief for him. I took the car home and pumped back up to 44psi. :lol:

Before the next check I bled the tires down to 36psi. I figured they'd do it anyway so I might as well not give them any excuse to accuse me of abuse.

I had noted some feathering on the shoulders very early on when I first rotated my tires at about 4000 miles. I ran 44psi after that and tires had even treadwear and passed inspection when I turned in the lease at 25,500 miles.

I would have told them to leave the pressures as they are and if its changed, I will not be returning. It worked for both my Toyota and Nissan dealers

 

[Nubo]

I would have told them to leave the pressures as they are and if its changed, I will not be returning. It worked for both my Toyota and Nissan dealers

"Never try to teach a pig to sing. It wastes your time and annoys the pig." -- Robert Heinlein

 

[sredlin]

I would have told them to leave the pressures as they are and if its changed, I will not be returning. It worked for both my Toyota and Nissan dealers

"Never try to teach a pig to sing. It wastes your time and annoys the pig." -- Robert Heinlein

You would think that by now the "pig" might have learned at least a few bars? It seems like Nissan should've realized by now that the Ecopia tires may still be the most efficient tires for the Leaf, but the rate at which they wear seems to suggest that higher tire pressure would help reduce wear and increase efficiency?

And although I was somewhat disappointed to have to replace my OEM Ecopia tires at 30k miles, I just replaced them with another set from Costco, because they had a nice sale and it seemed like the best bang for the buck, $450 out the door after taxes and fees. Maybe there's a better/more efficient tire out there at a similar cost, but I was not able to find it, and so I now have new Ecopia tires. The difference is they do have a higher load rating, which I'm hoping helps make them last longer than the stock tires?

 

[LeftieBiker]

I find that dealership mechanics will do 38psi, sometimes 40. Don't ask them to do sidewall maximum, as they actually have decent grounds (gauge error) to refuse.

 

[JPWhite]

$450 out the door after taxes and fees.

That is a good deal. I paid $535 at 30,000 miles and have been quoted the same for when I plan to replace them again at 60,000 miles in a few months. Need to check out Costco I suppose

 

[sredlin]

$450 out the door after taxes and fees.

That is a good deal. I paid $535 at 30,000 miles and have been quoted the same for when I plan to replace them again at 60,000 miles in a few months. Need to check out Costco I suppose

If you're going to be replacing them in a couple months, you can probably order them from Costco now while the sale is on and then get them installed later. And I assume that you know that you will need to join Costco for $55 annual membership before you buy tires from them. I guess that makes the cost more comparable to the $535 you paid, but you can shop at Costco for at least a year afterwards anyway. So here's a link to the tires that they have that fit my 2011 Leaf:

http://tires2.costco.com/SearchResults.aspx?SearchID=89aacab9-660f-4a5a-8bb2-4b8c1614391e" onclick="window.open(this.href);return false;

The actual OEM tires with the lower 89 load rating are $20 more expensive than the 91 load rating tires I bought, which doesn't really make sense to me, but that's the pricing? So based on your experience, I guess I'll just plan on replacing tires again at 60k miles, which I expect to hit within 3 more years. At least if I go with Ecopia tires again at that point, I should have a pro-rated mileage warranty credit to offset the cost a bit at that time.

 

[sredlin]

I find that dealership mechanics will do 38psi, sometimes 40. Don't ask them to do sidewall maximum, as they actually have decent grounds (gauge error) to refuse.

The Costco mechanic refused to put more than the door panel 36psi when I asked him for 42psi as I was about to pick up the car with the fresh tires. I explained to him how the 60k tires wore out along the shoulders like an under-inflated tire would even though I almost always had 40-42psi in them. Then he agreed to set the max hose pressure to 40psi and give me the hose to top them off, but he said he wouldn't do it. I feel like my OEM tires did about as well as I could have hoped for by making it to 30k, so I'll continue to run the new set at higher pressure and hope to get 30k miles out of them?

 

[woodgeek]

I think we have an answer here..... LIABILITY.

Users agree that 36 psi is obviously not optimal for the EP422s on a Leaf, but if Nissan tells you to use 40, they are liable for all tire-related failures/injuries/deaths that occur later, even if unrelated to tire pressure.

One wonders what the testing regime/certification process for a tire/vehicle weight would be...is it the tire manufacturer, the auto maker, or what?

But I think we can guess that that certification 'homework' wasn't or hasn't been done (yet?) for the EP422/Leaf combo...and the corps are covering their big azzes with a 'safe' 36 psi direction.

If it loses folks some mileage and increases their tires costs 50%, oh well...better than a messy brand-destroying recall.

 

[Bob]

Yes, 44PSI will give you longer tire life, but there are other tradeoffs to higher tire pressure. You may be more at risk of tire damage in a minor curb scrape. You may be more at risk to a blowout at a pothole. You may not get as good traction as otherwise in some situation.

I use the word "may" because I haven't done any testing to verify this. But you can bet that Bridgestone did test the Ecopias at low and high pressure, and Nissan also tested the Leaf with Ecopias at low and high pressure. I hope that they had good reasons for their recommendations.

Another issue is that tire pressure increases with temperature, so if you inflate cold and then drive hard, you will have even higher pressure. Even if you think that it feels fine when you first pump it up to 44PSI, it will not feel the same after 30 minutes of freeway driving. And it won't feel the same new at 44PSI as after 20k miles at 44PSI.

Bob

 

[JPWhite]

I think we have an answer here..... LIABILITY.

Users agree that 36 psi is obviously not optimal for the EP422s on a Leaf, but if Nissan tells you to use 40, they are liable for all tire-related failures/injuries/deaths that occur later, even if unrelated to tire pressure.

One wonders what the testing regime/certification process for a tire/vehicle weight would be...is it the tire manufacturer, the auto maker, or what?

But I think we can guess that that certification 'homework' wasn't or hasn't been done (yet?) for the EP422/Leaf combo...and the corps are covering their big azzes with a 'safe' 36 psi direction.

If it loses folks some mileage and increases their tires costs 50%, oh well...better than a messy brand-destroying recall.

If Nissan recommended 40psi then there would be no additional liability as long as that was their 'official recommendation'. Dealers will follow the official recommendation.

In the Bridgestone/Ford Explorer fiasco Bridgestone (to their own detriment) gave into Ford's pressure to recommend lower tire pressures than Bridgestone originally recommended in order to improve the quality of ride. Overheating tires was a factor in the tire failures and the lower pressure exacerbated the issue. Ford dodged much of the liability by throwing Bridgestone under the bus. It was a very complex issue, but it did reveal that tire manufacturers and car OEM's negotiate what to recommend to the public, it isn't a purely scientific formula.

Nissan went a little overboard with the LEAF battery safety, so one hopes they erred on the side of caution with tires as well.

 

[woodgeek]

Ok, so why are they sticking with 36?

 

[JPWhite]

Ok, so why are they sticking with 36?

You'll have to ask Nissan that, it's their call.

We can only speculate.

 

[DarkStar]

Yes, 44PSI will give you longer tire life, but there are other tradeoffs to higher tire pressure. You may be more at risk of tire damage in a minor curb scrape. You may be more at risk to a blowout at a pothole. You may not get as good traction as otherwise in some situation.

I use the word "may" because I haven't done any testing to verify this.

Correct, there is no evidence that 44 psi would cause any of the hypothetical situations you present in your statement. So I want to know why you suggest they could occur even though by your own admission you have no proof?

 

[Nubo]

Ok, so why are they sticking with 36?

My (probably uneducated) guess is that 36 psi gives the softer ride that Nissan believes will appeal to the most buyers.

 

[JPWhite]

Ok, so why are they sticking with 36?

My (probably uneducated) guess is that 36 psi gives the softer ride that Nissan believes will appeal to the most buyers.

+1

 

[Phatcat73]

Now that we have a little snow/ice on the ground, I'm convinced the factory ecopias, 89 series, are a starter tire intentionally designed to wear out prematurely and perform poorly. Last winter the car slid all over the place in the snow with around 8/32 tread. Now that we have some ice/snow on the ground I was able to test out my newly acquired 91's ecopias. They work great and even seem quieter! Plus the 91's have a 65,000 mile warranty.

 

[Bob]

In reply to DarkStar's question for me, I just wanted to make sure that people think about the consequences of their actions and realize that the collective wisdom of this list is really good, but may not be as good as the experience and controlled testing of Nissan and Bridgestone engineers.

It is almost certain that higher pressure will reduce rolling resistance, and that will improve range. We've seen graphs of that. But that isn't the only effect of higher pressure. I am trying to get people to think of more than just one parameter, not just tire life or range.

I said that there ARE tradeoffs to higher tire pressure. I don't have proof of what those tradeoffs are. I proposed a few possible reasons to get people to think. It would take time-intensive and expensive testing to prove or disprove any of those theories. Those are the kinds of things that Bridgestone and Nissan do. My point is that there's a good chance that Nissan engineers aren't absolute morons who advise us to do stupid things without a reason. It could be that there are good reasons for their recommendations.

We all make the mistake of drawing conclusions from too little data. It's true that one data point is more data than zero data points, but non-controlled experiments have very often led intelligent people astray. Some have said that they pump their tires high and they don't wear well. Others have said that they pump the tires high and they wear well. And others have said... I think we've heard every possible scenario.

But I do have one data point that I could share. I inflate my tires to 40PSI. I had a bad blowout in one tire when I hit the curb at low speed. The tire was ruined. I've hit the curb with tires on other cars in the past and not had any damage. But I'm not going to draw any conclusions from this. It could be that Ecopias are weaker. Or it could be that high tire pressure contributed to the damage. Or it could be that I hit the curb hard. But it made me think.

Bob
Disclaimer: I have no connection with Nissan or any of its engineers. But I am an engineer.

Bob wrote:
Yes, 44PSI will give you longer tire life, but there are other tradeoffs to higher tire pressure. You may be more at risk of tire damage in a minor curb scrape. You may be more at risk to a blowout at a pothole. You may not get as good traction as otherwise in some situation.

I use the word "may" because I haven't done any testing to verify this.

DarkStar replies:
Correct, there is no evidence that 44 psi would cause any of the hypothetical situations you present in your statement. So I want to know why you suggest they could occur even though by your own admission you have no proof?

 

[BrockWI]

Another note on tire pressure. We run snows, Brigstone Blizzacks on the Leaf and Nokian Hakka's on the VW TDI. Out last house had a 75 foot rise over 200 feet driveway out. Often we forgot to leave a car "up" at our other garage by the road and had to try to make the climb up the driveway with it snow covered. The trick we used was to deflate the tires to 10psi to get up the driveway and re-inflate. It was amazing the traction you get with a Nokian Hakka at 10psi, you would swear you have chains on.

By no means am I recommending running them that low on any regular basis. But if I didn't have dedicated snows I would be running my all seasons at about 30psi in winter for better traction. Yes you will loose rolling resistance, but sometimes you need just that, a LOT of rolling resistance