: STS-V Tire Pressure



Guy.Seminerio
06-19-13, 09:36 PM
I have stock rims and i run about 35-37 psi on the tires. During a long run on the highway the pressure reads 37. Cold it's 35. I use nitrogen. I have michelin pilot sport a/s tires. Tires are fine. Good grip, ride, noise level. They're all wearing on the edges which suggests I need to add more air. Is this normal? What are you guys with stock sizes running?

PGA2B
06-19-13, 11:43 PM
I am running 28 hot rear and 32 hot front.

Guy.Seminerio
06-20-13, 12:10 AM
Any wear issues or to be determined?

todrules
06-20-13, 01:07 AM
I run about 32 all around, although my right rear sensor is acting up after about 10 miles of driving. I replaced the left front a year ago, you'd think somebody would figure out how to build the sensors that last.

parkeraire
06-20-13, 06:56 AM
Are you supposed to go with tire manufacturers recommended pressure or car manufacturer ?

1madstsv
06-20-13, 07:21 AM
I run 30psi all the way around.

Fierofiend
06-20-13, 08:42 AM
I think I may have the same tires, with the same problem. I was noticing wear on the outer edges of my tires and took it to get the alignment checked. The rear is spot on, they made no adjustments, those have always worn even. They said the front needed toe to be pulled in a few degrees, so they did that. I haven't driven it enough to know if it slowed/stopped the problem.

I run about about 35 all around. I did the same as you and ran the fronts up to 40 to see if it would help the wear, it made no change and they continued to wear the edges. It is NOT cupping/feathering, it is just inside/outside wear on both fronts, from what I can tell. Are your tires just wearing, or are they 'chunking' off? Is the wear smooth or feathered? Post a pic.

PGA2B
06-20-13, 09:03 AM
Any wear issues or to be determined?

No weird wear. I got extra milage out of my first set of Hankooks. I just put Toyo Proxies 4 Plus on the back as my last pair of Hankooks wore out in a year. AZ heat eats tires!!

Guy.Seminerio
06-20-13, 09:03 AM
Will post pics thanks. And parkeraire, to answer your question I've never followed the mfr's recommendation on tire pressure. I've always adjusted to account for any uneven wear I'm experiencing; more air for wear on the outer edges, less air for wear in the middle. I've always been taught that the mfr recommends a certain tire pressure based on giving you a comfortable ride, so lower pressure than it should be. Also, I wold never exceed what the tire mfr has listed on their tire. But I imagine with the caddy being a performance vehicle, GM wouldn't have listed conservative tire pressures for comfort because they would be doing that at the expense of characteristics one desires out of a performance vehicle like stability, quicker turn in, control, etc. could be wrong though.

Guy.Seminerio
06-20-13, 11:58 AM
Crap just checked and on all 4 tires, especially the front two, I'm wearing more on the outsides. The edges are wearing more than the middle in general but the outsides are getting it worse. Seems to be wear, not chunking. I took pics. Ill post later when I'm at the computer. So alignment it is I guess. Any particular reason I should give my cadillac to cadillac as opposed to say Firestone service for this alignment?

YoungBlood_STSV
06-20-13, 04:28 PM
Crap just checked and on all 4 tires, especially the front two, I'm wearing more on the outsides. The edges are wearing more than the middle in general but the outsides are getting it worse. Seems to be wear, not chunking. I took pics. Ill post later when I'm at the computer. So alignment it is I guess. Any particular reason I should give my cadillac to cadillac as opposed to say Firestone service for this alignment?

I had the tires you have. Ran pressures from 30-40psi. Couldn't stop or slow the shoulder wearing. Ended up replacing the tires at 18k and 22k miles (rears and fronts, respectively). Moved onto Conti DWS and got somewhere around 32k miles out of the rear tires and they wore 100% evenly. The fronts are still on the car and will probably go another 3k miles...which will be about 39k total.

Those Michelin's did give decent grip; but for the price they are I expect more than "decent grip" from the tire. Saving about $100 a tire I lost maybe 10% of maximum grip and gained better winter traction, longer life and I've been able to use all of the tread.

If you're from the South or West - the options for tires with equal grip are huge; ditch the Michelin's. If you're in the NE, NW, or Mid-West I'd go Conti DWS or Hankooks.

Guy.Seminerio
06-20-13, 05:56 PM
I'm in nc but will be back to living in ny in just under a year so the continentals will do. So grip isn't quite as good you say. This isn't a huge concern for me. They're all seasons after all. I'm not trying to shave tenths of seconds off my work commute. How about road noise? Better, worse or inconclusive? Also, you got 32 out of the continentals in the back, what did you replace them with and how do they compare? Thanks.

YoungBlood_STSV
06-20-13, 08:18 PM
Replaced them with two more Continental DWS's. Haha. Road noise is probably similar, when new the Continental's are very quiet.. But I drive with music on 95% of the time and don't hear the tires at all. I'm in the same boat as you, I'm not taking corners at full speed on my way to work in traffic so why spend $300+ on a tire and not use it?

The longitudinal grip from the DWS's is great, it's the lateral grip that's down from the Michelin's. They also have DW's if you can forgo the all-season part. Those are a bit more grippy.

Guy.Seminerio
06-20-13, 10:40 PM
I'm a little concerned with having more longitudinal grip. I feel, and correct me if I'm wrong, that if my tires aren't as quick to lose traction when I accelerate, I will be more susceptible to wheel hop.

Guy.Seminerio
06-20-13, 10:45 PM
The side of the tire that is more worn is the outside portion. Those are both of the front tires. Same story in the back, couldn't get a clear picture.

1madstsv
06-20-13, 10:58 PM
To stop wheel hop you either want a hard tire that will spin very easy our a very soft tire that will just hook and go. It's when you are in the middle you can have issues. Sad thing is most tires are in the middle our at least the better ones. It looks like the tire could have to much air let it down to 30-32 psi and see if it goose away.

Guy.Seminerio
06-20-13, 11:13 PM
too MUCH?! do you mean too little? It's pretty clear I need an alignment by the fact that there is more wear on the outer edge (left in the pic) than the inner edge. But the fact that the edges are wearing more than the middle would suggest i need more air, not less. If i was wearing in the middle, I'd have to take air out. Are these tires shot or do I have some time on them?
MadSTS-V, what kind of tires do you have? Do you have hop?
has anyone quelled wheel hop? if so, how? Tires? what kind?

Fierofiend
06-21-13, 09:38 AM
Those tires are in much better condition than mine are. I will post pics of my tires tonight/tomorrow. Only my fronts were wearing like this, the rears are fine. I will try to post my before/after alignment specs if I can find the sheet. I will NOT be purchasing these tires when I swap out the fronts, I'm satisfied with the rear wear/grip however..

1madstsv
06-21-13, 11:00 AM
I say too much air do to Streching the side wall out and giving the choppy look. I would try letting 5 psi out all the way around. I only run 30psi in my corvette. I had Bfg kdw new tread 2's on my 06 and had no hop. The 08 has toyo tr1 tires they are a good tire so far not as good in the turns as the Bfg but ok but they still will hop just a little. I only run 32-30 psi in them. Also tire wear like you have could be a balance issue.

Guy.Seminerio
06-21-13, 12:23 PM
Well I'm gonna work the alignment before I start playing with tire pressures. I actually just had my wheels rebalanced at cadillac. The what do you call it balancing. The expensive one that's like 90 bucks. Is there any reason I should go to cadillac over some other reputable place to get my alignment?

1madstsv
06-21-13, 01:30 PM
It's your money but why not try the pressure adjustment first. Last time I checked air was free?

Guy.Seminerio
06-21-13, 01:52 PM
And losing air is even more free. So I need to lose about 5 PSIs per tire. It just doesn't add up that less air would stop wearing the edges. Ill try it. Tomorrow morning. I hear it isn't good to drop air on hot tires. We'll see. Meanwhile, can I get a second opinion on that solution and also the alignment question. Thanks. And thanks 1madsts-v

YoungBlood_STSV
06-21-13, 02:14 PM
Well I'm gonna work the alignment before I start playing with tire pressures. I actually just had my wheels rebalanced at cadillac. The what do you call it balancing. The expensive one that's like 90 bucks. Is there any reason I should go to cadillac over some other reputable place to get my alignment?

What makes you think you need an alignment? You hit something? Car drift out of lane when you let go of the wheel? If the answer is no then you likely don't need one. Don't waste $100 to learn you have shitty tires.



You have shitty tires.

Guy.Seminerio
06-21-13, 05:02 PM
Guy, look at the pictures. The outer edge is wearing more than the inner edge. Did you not see that? Or do you in fact see that and still believe my wheels are properly aligned??

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You don't have to hit something for your wheels to go out of alignment btw.