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Discussion Starter · #1 ·
Cliffs: new tires are causing my MPG to plummet, wondering if low pressure is the culprit.

2007 RAV4 i4 AWD, 119k miles, have had for 3 months, great car. Bought it with 113k, road tripped ~ 6k miles over the summer, managed upwards of 31 mpg on the highway at 65. City driving was closer to 23-24. Not terrible.

Car had Yokohama Avid Envigors in the stock size 225/65HR17 when I got it, they looked fairly decent treadwise, so I didn't think about them, just drove.

http://tinyurl.com/j2hlzdy
https://www.yokohamatire.com/tires/detail/avid_envigor

Noticed the Tire Rack ratings were good generally but indicated they sucked in snow and ice so I figured I'd wait and see for myself (I walk to work, so no HUGE deal, but, wet traction is a concern).

Tires were inflated to ~ 40 psi, didn't change anything, just drove.

Two weeks ago I took an off-camber on-ramp a little too fast (it had been raining for days so it wasn't oil on the road) and I felt all four tires break loose. I eased off the gas and steered gently and she came back under control. Scared the **** outta me, guardrail and curb weren't that far off.

Decided to get new tires. Went with these Pirelli's in the stock size, H rated:

https://www.pirelli.com/tires/en-us...heet/scorpion-verde-all-season-plus#/overview

PirelliÂ*Scorpion Verde All Season Plus

Installer inflated them to 35 psi, I didn't think much about it, decided to drive on them and see how they felt. Dry response was great, no problems, haven't driven them in the rain yet.

Just drove to Philly and back, 113 miles, and burned HALF A TANK OF GAS. Was at the 1/2 mark when I started, low fuel light came on just as I pulled in the driveway. AC was off, road was dry, I did have the sunroof cracked on the way there and open on the way back, so there was some drag, but holy mother of GOD, I should have burned 1/4 tank, maybe a bit more.

Car is in the garage, tires are cooling, they now read 36.5 psi. In the AM I plan to inflate them to the max of 44 psi cold. I'm driving to Philly again Friday, almost the same route. I'll be able to see if the MPG's are back where they are supposed to be.

Checking the specs now, the Yoko's max psi is 51 (!) and the Pirelli's is 44. So, I'm going to see how it rides at 44 and if MPGs are ok.

Here are my old tires on Craigslist, you can see tread depth: (4) Yokohama Avid Envigor 225/65HR17 *USED*

What say ye? Were these Pirelli's severely underinflated?

They are NOT directional, or if they are, I don't see the markings.

TIA,

-kj-
 

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Cliffs: new tires are causing my MPG to plummet, wondering if low pressure is the culprit.

2007 RAV4 i4 AWD, 119k miles, have had for 3 months, great car. Bought it with 113k, road tripped ~ 6k miles over the summer, managed upwards of 31 mpg on the highway at 65. City driving was closer to 23-24. Not terrible.

Car had Yokohama Avid Envigors in the stock size 225/65HR17 when I got it, they looked fairly decent treadwise, so I didn't think about them, just drove.

YokohamaÂ*AVID ENVigor (H- or V-Speed Rated)
https://www.yokohamatire.com/tires/detail/avid_envigor

Noticed the Tire Rack ratings were good generally but indicated they sucked in snow and ice so I figured I'd wait and see for myself (I walk to work, so no HUGE deal, but, wet traction is a concern).

Tires were inflated to ~ 40 psi, didn't change anything, just drove.

Two weeks ago I took an off-camber on-ramp a little too fast (it had been raining for days so it wasn't oil on the road) and I felt all four tires break loose. I eased off the gas and steered gently and she came back under control. Scared the **** outta me, guardrail and curb weren't that far off.

Decided to get new tires. Went with these Pirelli's in the stock size, H rated:

https://www.pirelli.com/tires/en-us...heet/scorpion-verde-all-season-plus#/overview

PirelliÂ*Scorpion Verde All Season Plus

Installer inflated them to 35 psi, I didn't think much about it, decided to drive on them and see how they felt. Dry response was great, no problems, haven't driven them in the rain yet.

Just drove to Philly and back, 113 miles, and burned HALF A TANK OF GAS. Was at the 1/2 mark when I started, low fuel light came on just as I pulled in the driveway. AC was off, road was dry, I did have the sunroof cracked on the way there and open on the way back, so there was some drag, but holy mother of GOD, I should have burned 1/4 tank, maybe a bit more.

Car is in the garage, tires are cooling, they now read 36.5 psi. In the AM I plan to inflate them to the max of 44 psi cold. I'm driving to Philly again Friday, almost the same route. I'll be able to see if the MPG's are back where they are supposed to be.

Checking the specs now, the Yoko's max psi is 51 (!) and the Pirelli's is 44. So, I'm going to see how it rides at 44 and if MPGs are ok.

Here are my old tires on Craigslist, you can see tread depth: (4) Yokohama Avid Envigor 225/65HR17 *USED*

What say ye? Were these Pirelli's severely underinflated?

They are NOT directional, or if they are, I don't see the markings.

TIA,

-kj-
First CR rate these tires as recommended as does Tire Rack. They are however under the Category of Truck tires which I would think have a more aggressive tread compared to PERFORMANCE ALL-SEASON TIRES... I have the General Altimax RT43 out of that category. That might be the reason for the drop in MPG. As for PSI the recommended for the Rav is 32... I do take mine to 35 to get better gas millage not so sure the max PSI is good for the tire...

https://www.kaltire.com/the-right-tire-pressure-why-the-maximum-isnt-the-best/
 

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Discussion Starter · #3 ·
Thanks! I ran the Altimax's too on my Camry. Loved them! Great tire.

Never really thought about those, wish I had. Would have given them serious consideration.

Here is a Tire Rack comparison between 4 tires:

https://drive.google.com/file/d/0BwnCvTOIHxeLa3cxR09ORW1YNDQ/view?usp=sharing

BRIDGESTONE
DUELER H/L 422 ECOPIA
[close to OEM?]

PIRELLI
SCORPION VERDE ALL SEASON PLUS
[what I bought]

GENERAL
ALTIMAX RT43 (H- OR V-SPEED RATED)
[car tire I have owned before and like a lot]

YOKOHAMA
AVID ENVIGOR (H- OR V-SPEED RATED)
[what I replaced]

What I notice:

- Pirelli's are the best RATED overall, but the amount of miles reported in the survey is the lowest of the four.
- Pirelli's tread width at 7.2" is the largest and .7" more than the Yoko's. <= is this my MPG difference? Seems like it.
- Pirelli's and Yoko's weigh 28# per tire, the others 25# (less rotational mass = better MPG)
- The Yoko's are HP All Season, the Generals are Touring All Season, and the others are Crossover/SUV Touring All-Season <= other MPG impact?

I am going to complete my drive home to record the MPG with the Pirelli's at 40 psi. I predict it won't be THAT much better than 35 psi (still worse than the Yoko's) and not worth the difference is ride quality (it is very significant).

Then I expect I will drop them back to 35 psi and leave them there.

I think how this is going to shake out ... the change in tire category, with the extra width, and the tread compound/pattern, basically means I bought much stickier tires, and probably the best possible for the vehicle ... but with a significant MPG hit, which I will continue to monitor.

Thoughts?

-kj-

p.s. yeah ... still reading? I'm weird about this stuff.
 

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May I ask just how you are actually calculating your gas mileage? IMO if what the gauge reads has any input into your figuring the results are highly suspect.
Just drove to Philly and back, 113 miles, and burned HALF A TANK OF GAS. Was at the 1/2 mark when I started, low fuel light came on just as I pulled in the driveway. ... I should have burned 1/4 tank, maybe a bit more.
 

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Discussion Starter · #5 ·
I calculate it by dividing the miles driven by gallons, recording it the same way I have done it since I got my license in 1979.

To be fair, the first and only tank so far I calculated MPG on with the tires was only 100 miles on the new ones, 200 miles on the old ones. It was 90% highway and the final was 25.4; based on past performance, that should have been closer to 28 or 29.

I also know, having driven this car about 6,000 miles since getting it a few months ago, I know *EXACTLY* how the gas gauge behaves, how it differs at the top vs. the bottom, when the low fuel light comes on and how many gallons are left at that point, and how this all changes on highway vs. city driving. I also know the variables that can throw off the calculation (different stations/pumps, amount of gas added after the click off). We can't pump our own gas in NJ so I am at the mercy of the attendant but always go to the same station and pump.

In rough terms, based on past performance, on the highway, I have consistently seen 29-30 (high of 31) MPG on the highway, 22-24 in city driving, which is comparable to the EPA ratings.

Under the best conditions, I have gone well over 400 miles before the low fuel light came on, I forget, I don't have the records with me, I am travelling for work.

I have seen ~250 miles before getting to the 1/2 tank mark, then generally the car gets about 100 miles per quarter tank as reported on the gauge.

So here is the problem...

When I drove to Philly and back for the first time with the tires, newly installed, the gas gauge was at the 1/2 mark. When I returned from Philly (120 miles RT) the low fuel light had come on. The MPG calc was worthless because 2/3 of the miles were on the old tires. But I do know, after having driven this car for months and this route for years, that there is NO WAY a round trip to Philly take a half a tank of gas. No possible way.

That is why I put the PSI up to 40 and drove again to Philly, and I will return in a few days, and immediately verify the MPG, and will continue to calculate it as I always have. Yes I know it's not a lot of data. But I also know this car very, very well. We'll see if my suspicions are correct.

The ride quality at 40 psi is horrible, and I predict (based on what I saw yesterday) that the MPG will be slightly better than at 35 psi but it's not worth the deterioration in ride quality. So I will probably end up with them back at 35 psi and enjoy the ride, and just eat the lost fuel economy, since tires are not returnable.

My regret at this point is not having considered the Altimax's, they were cheaper and probably would have been a better choice, but, this RAV4 is in fact a truck, not a car, and don't regret going with truck/SUV tires...

-kj-
 

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kjarrett: I have a different perception of my RAV. To me it's a car, not a truck. That's why I put Michelin Defenders on mine and consistently get 21-22 around town and 26-28 on the highway along with a quiet, smooth ride, good handling in wet weather. I keep 35lbs in mine.
 

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Okay sounds accurate except for the NJ situation which could easily introduce a 1/2 gallon error especially if you're paying cash and the attendant wants to stop on an even dollar amount (1/2 gallon @ $2/gal.)

When I saw the "half tank" it reminded me of a friend who thinks his Honda Odyssey gets better mileage than his Corolla because it goes farther on half a tank.
 

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Discussion Starter · #8 ·
Thanks, this is my first RAV, but our second, my wife has an '05 L that we love. The 4.3 is a substantially larger vehicle, behaves / rides differently ... but I certainly could have gone with car tires ... guess I was too swayed by the Tire Rack reviews. :/

Hopefully I'll have better data once I've gotten a few tankfuls with these Pirelli's on. Seems like my MPG was abnormally high (near and above 30 highway) so maybe I was just getting more than I deserved, lol!

-kj-
 
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