245/45/17 Tire Pressure ?

[Meaux]

I had my Avon 550's (245/45/18) mounted and balanced on the 350Z (18x8) wheels yesterday and was wondering, what pressures are ya'll running for this size of tire? You guys are right about the 245's, they fit the wheels perfect!

So, I checked em' right out of the tire shop and the rights had 45psi, the lefts had 35psi...must hae been 2 different guys doin the work.

I'm sure the fronts and rears would be different, and right now I'm at 35psi on all 4 feet...Dang tires are smooooth...much better ride than the Michelins...what a good time to dump Michelins.....:-)

Pictures comming soon....the "computer genius" sleeps till 12......:-)

[maxnix]

Maybe 38 psi in the front for the additional weight and incresed dynamic loading. Same in the rear when you are hauling people or luggage.

Michelins must have been really worn as I have drivne mine to the cords. Keeping the suspension to as new OEM specifications really helps tire wear, in addtion to frequent rotation and flipping.

[Falkdesigns]

I run 42 psi in my 245-40-18's.

[zinkie13]

I run 41 on my 245/45-18's

[rsiwicki]

I am relatively new to the higher performance style tires and so when I got my new 18" wheels this past year I tried 35, 40, and 45psi. I could not really notice a significant difference between the different pressure with 18" wheels like I did when I had the 15" wheels on. I am running 40psi and all seems to be in good order. Try them all out to see what you like best.

I would really like to know how you like your Avon's....I will be replacing this set with Avons probably this fall. I drive like in the movie Days of Thunder....I move really fast but eat up tires like nobody else. The tree huggers just love me :-)

[szh]

On my M45, I run 36psi all around on 245/45-18 Goodyear Eagle F1 GS-D3.

The manual has the same tire pressure listed for all four wheels (32 psi for the OEM 235/45-18 tires...although I ran the OEM Bridgestones at 36psi too), so I figured I would not try for different front/back values either.

Z

[szh]

Keeping the suspension to as new OEM specifications really helps tire wear, in addtion to frequent rotation and flipping.

Agreed! I rotate front/back every 3,750 miles (basically at the oil change point) and re-balance every 3,000 to 6,000 miles - depending on the tire.

All-wheel alignments periodically too - about every 5,000 to 10,000 miles depending on how the car seems to be handling.

Z

[AZhitman]

I have 255/40/18's and run 40psi F and 37 psi R.

[Meaux]

I put 40psi in front, and left 35psi in the rear.

Had a heck of a fright today, going over a bridge and gettin right to the top, I see this 6' 2x4 flying into the air after getting hit by on-comming car, and it looked like it was going to hit me square in the windshield, so, grippin the steering wheel so as to not turn, I closed my eyes and waited for the shock. Luckily, it must have hit the road in front of me cause I felt go under both drivers side tires.

Then I thought, "this would have never happened if I hadn't just put on new tires".

Good side, no damage I can see or tell.......

[szh]

Ouch!

Your rims may have been damaged. See if they require a rebalance. Any chance of collecting from the "owner" of the 2x4? Was it a piece of the bridge?

Z

[maxnix]

Being at higher pressures in situations like that will save your rims, and tires. Check them anyway.

[Jason B]

[st3]

On my M45, I run 36psi all around on 245/45-18 Goodyear Eagle F1 GS-D3.

The manual has the same tire pressure listed for all four wheels (32 psi for the OEM 235/45-18 tires...although I ran the OEM Bridgestones at 36psi too), so I figured I would not try for different front/back values either.

Z

How do those work on the M? I liked those tires on my old car and have been thinking about putting them on my M because I hate the Michelin's so much.

[elwesso]

I run about 35 psi inthe front and a little over 40 in the rear... My rear tires arent to the proper load capacity so i pump them up. I can tell too because they arent wearing right.. Next set of tires is gonna have a 101 load rating

[szh]

How do those work on the M? I liked those tires on my old car and have been thinking about putting them on my M because I hate the Michelin's so much.

The Goodyear Eagle F1 GS/D3 is an excellent tire (scores 10 out of 10) for wet conditions - on par with my reference: the Firestone Firehawk SZ50EP for this, and a very good tire for other stuff scores (8-9 out of 10).

Not exceptionally quiet (7/10), but decent enough that I am not concerned about that. Dry road stickiness is very good (8/10), but not quite on par with the Firehawk SZ50EP (9+/10).

My experience with the Goodyears on my wife's car (in a different 205/55-16 89V size) is that they require frequent rebalancing (every 3k miles or so.) I am hoping that the new 100W rating of the 245/45-18 size (previous was 96Y, and may still be available) means that the tire is stronger and will not require re-balancing as much.

I have noticed one other interesting thing though. These 100W tires have stiffer sidewalls than the Bridgestone Turanza ER33 (235/45-18 94W) that came OEM on the M. When driving at 9/10 (which I sometimes do on curvy roads), the suspension seems to be a bit more disconcerted with the stiffer sidewall ... the car is a bit more "hoppy" on bumps in curves.

I have had to slow down by about 5% on some roads (that I drive a lot and am very familiar with) to get the same degree of surefootedness that I had with the softer sidewall tires.

So, when these wear out, I am going to try some softer sidewalls (probably in a 95 or 96 load index) like the Avon Tech 550 or the Michelin Pilot Sport A/S to see if I can restore the handling in extreme situations. I think the suspension was more geared for the 94 load index tires that came as OEM.

Of course, I must emphasize that I am talking about some extreme situations in this regard! There is a stretch of curvy mountain road near my house that has a speed limit of 45mph that I could easily take at 90+ mph on the SZ50EP (on my Q45) and at 85+ mph on the Turanza ER33 (on my M45) , that I am now taking at 80+ on the Eagle F1 GS/D3.

FWIW, most people do not drive this section of road any faster than 65mph or so. I have kept up with Porsche Turbo 911's on this twisty road with ease.

BTW, I truly wish that the Firestone Firehawk SZ50EP were still made ... those were the best tires I have ever used ... in 30+ years of driving! The new Firestone Firehawk Wide Oval may be similar, but it is not yet made in an appropriate 18" width (like a 235/45 or 245/45) that I can try out.

I do think that people with 17x7.5 or 17x8 wheels ought to try the 245/45-17 Wide Ovals and see how they work out.

Z

[maxnix]

Wide Ovals seem to be a good tire, but no SZ50 EP in spite of being made in Japan. Seems like they backed off the tchnology a little bit (compare at Firestone site) and most previous users note they are not as precise as the SZ50 EP in TR customer reviews. Since the Avon Tech M500 has a 97 load rating in the 245/50-16 size for my wife's FY33, it is the choice over the WO 96 load rating (SZ50 EP was also 97).

The Avon 550 should not be confused with the above "Summer" performance tires as it is an all season tire and not as good in the rain or dry as its M500 sibling.

[szh]

The Avon 550 should not be confused with the above "Summer" performance tires as it is an all season tire and not as good in the rain or dry as its M500 sibling.

Yes. But, the only issue is the the M550 is available in 245/45-18 and the M500 is not (or, for that matter, in any size that can be used on the M45 OEM wheels.)

Z

[szh]

Wide Ovals seem to be a good tire, but no SZ50 EP in spite of being made in Japan. Seems like they backed off the tchnology a little bit (compare at Firestone site) and most previous users note they are not as precise as the SZ50 EP in TR customer reviews.

I noted that ... although one recent review from a user of the original SZ50 and SZ50EP seemed to be more positive than the other reviews. I might try them on my wife's car next change (if we have the car then ... we keep debating when to replace it - the 1997 Acura 2.2CL seems to keep motoring along without any difficulties, although I detest the low power!) since I think they did have a 205/55-16 size available.

Z

[jamesmost]

95 Q 36psi all 4