: CTS-V Run-flats - Bad News, good news



tedcmiller
08-30-12, 11:26 PM
Most people ask for the bad news first, so here it is. As far as I know, there is still no one who makes exact replacement tires in run-flats for the 2009 and later CTS-V.

However, the good news is that as long as you are willing to go a little slower, Pirelli makes 19 inch tires in the correct width and aspect ratio for the CTS-V. The Pirelli run-flat front tire (255/40ZR19 on the CTS-V) is a W rated tire which is a little less than the 96Y rated front tires that normally come on the CTS-V. That means your top speed will be limited to 168 mph. Also, although the rear tire (285/35ZR19 on the CTS-V) is not a metric tire, the Pirelli run-flat P285/35ZR19 (99Y) is. So as long as you are able to overlook these differences, Pirelli has run-flat tires for the CTS-V. Both of these run-flat Pirelli tires are P Zero tires (not all P Zero tires are run-flats).

kehock
08-31-12, 08:05 AM
having had run flats on my 08 sts-v i'd say your bad news is actually good news.

JFJr
08-31-12, 12:30 PM
However, the good news is that as long as you are willing to go a little slower, Pirelli makes 19 inch tires in the correct width and aspect ratio for the CTS-V. The Pirelli run-flat front tire (255/40ZR19 on the CTS-V) is a W rated tire which is a little less than the 96Y rated front tires that normally come on the CTS-V. That means your top speed will be limited to 168 mph. Also, although the rear tire (285/35ZR19 on the CTS-V) is not a metric tire, the Pirelli run-flat P285/35ZR19 (99Y) is. So as long as you are able to overlook these differences, Pirelli has run-flat tires for the CTS-V. Both of these run-flat Pirelli tires are P Zero tires (not all P Zero tires are run-flats).Do you have the Pirelli's on your car? If so how do you like them? I needed tires about a year ago, and bought Bridgestone Potenza S-04's because no runflats were available and these tires had a higher wear rating than the stock Michelin's. I like the Bridgestone's but wish they were runflats.

Jud

tedcmiller
08-31-12, 03:54 PM
No. I put Pirellis on my wife's 1998 Mustang Convertible (it was top-of-the-line and very powerful). Nobody had heard of run-flats back then. They were H rated and considerably slower than the tires that came on the car but they were fine. As far as run-flats are concerned, I had both Goodyear and Bridgestone run-flats (which neither makes anymore) on my 2004 and 2005 CTS-Vs. I liked them both just fine. The Bridgestone run-flats tended to flat-spot more than the Goodyears, but I got over 20,000 miles out of the Bridgestones, whereas I got only 10,000 out of the Goodyears. I will probably put Pirellis on my 2009 when it needs tires to get the run-flats (it has only about 8000 miles on it as I am retired).

Johnxlrv
08-31-12, 07:21 PM
Since I am thinking about tires...my XLRv has those Pirelli Euforia run flats. (not quite the bad boy size of the CTS...255/40/19)...that are OK. I am finding that these are not for those who want the edge in performance (lateral g force for example), or with the "W" rating, not going too fast...

But, I am satisfied with these for a few reasons...excellent wet weather traction, decent ride and the fact that I can potentially go 50 miles at 50 mph on a flat tire...or more if I stop to let it cool.

Don't expect any tire shop to be willing to repair...liability is too high...and consider having the tire pressure sensors...so you will know that you have a flat...it is not all that apparent.

BigDog001
08-31-12, 07:46 PM
Most people ask for the bad news first, so here it is. As far as I know, there is still no one who makes exact replacement tires in run-flats for the 2009 and later CTS-V.

However, the good news is that as long as you are willing to go a little slower, Pirelli makes 19 inch tires in the correct width and aspect ratio for the CTS-V. The Pirelli run-flat front tire (255/40ZR19 on the CTS-V) is a W rated tire which is a little less than the 96Y rated front tires that normally come on the CTS-V. That means your top speed will be limited to 168 mph. Also, although the rear tire (285/35ZR19 on the CTS-V) is not a metric tire, the Pirelli run-flat P285/35ZR19 (99Y) is. So as long as you are able to overlook these differences, Pirelli has run-flat tires for the CTS-V. Both of these run-flat Pirelli tires are P Zero tires (not all P Zero tires are run-flats).

I have had run flats before - they were terrible and unbelievable expensive to replace -- I recently had a flat with my V -- I used the tire repair cylinder and it worked great -- and it lasted for days until the new tire came in -- I am very impressed with solution GM has -- it was easy and worked great for me.

JFJr
08-31-12, 08:43 PM
Great, technology never stands still. What you experienced years ago with runflat tires is not relevant. If you don't track your car, who cares? 99% is fine for a street car. Don't assume that everyone has to race; enjoying a high performance car on the street is enough. Plenty of performance is available without burning daddy's money on new tires every 10,000 miles. Enjoy it while you can!

Jud

tedcmiller
08-31-12, 09:33 PM
Different people have different ideas about run-flats. I, personally, would rather keep driving on a flat than stop on possibly bad ground, possibly at night in the dark, unload the trunk, and fool around with pumps and other stuff. Granted the stiff sidewall of run-flats contributes to lesser ride comfort and more expense. But, to me, it is worth it. The absence of run-flats on my 2009 CTS-V was almost a deal breaker. I will replace the existing tires with run-flats at my earliest convenience. BigDog001 (post #6) has his opinion, and I have mine. I am not impressed with GMs solution. The CTS-V has tire pressure sensors. My Cadillac dealer plugged a run-flat for me that had lost all air pressure. The word is that a plugged tire cannot be run at maximum speed. So what, I never went that fast anyhow.

As far as the slower speed is concerned, 168 mph (W rating) is a lot faster than I will ever go. JFJr has the right idea.

As a matter of accuracy the Mustang that I put the Pirellis on was a 1988, not a 1998.

Jinx
09-01-12, 03:12 AM
I have runflats on my Corvette.
I have experienced sudden total pressure loss at freeway speed, thanks to some nasty road debris.

CTS-V's lack of runflats is a big negative to me. It might keep me from taking the Caddy plunge. I know, non-runflats can give better road feel, but... soldiers don't wear running shoes.

Give me the Goodyear Supercars or the Michelin PS2s in runflat and stock sizes and I'd be happy. I look forward to hearing about the Pirellis if someone tries them. In terms of summer grip are they in the same league as the other two?

BigDog001
09-01-12, 07:07 AM
Great, technology never stands still. What you experienced years ago with runflat tires is not relevant. If you don't track your car, who cares? 99% is fine for a street car. Don't assume that everyone has to race; enjoying a high performance car on the street is enough. Plenty of performance is available without burning daddy's money on new tires every 10,000 miles. Enjoy it while you can!

Jud

Agreed -- all I was saying is that the tire sealer worked extremely well -- I did not trust it at first but it far exceeded my expectations and was a lot easier than changing a tire. I was able to drive 130 miles to where I was going with no loss of pressure (I did have to wait for the tire to come in, another 2 days and the sealer held the entire time) -- when I had a run flat (on a 2009 vehicle) it went flat after about 35 miles -- and yes they are probably better now.

.... and yes I do track my car occasionally for the fun of the experience.

tedcmiller
09-01-12, 01:39 PM
I never "track" my car. Just FYI there are less run-flat tires in the Pirelli P Zero line than there are non-run-flat tires. I might be the first to try the run-flat Perillis. TireRack does not carry the run-flat Pirellis. Yes, they are expensive, but not a lot more expensive than Michelin PS 2s.

Getting out of the car, and fooling around with pumps and other stuff might be less of a problem than changing a tire, but it is still more trouble than driving on.

neuronbob
09-01-12, 01:56 PM
Ted, thank you for your dogged determination on this issue. While I do not have a desire for run-flats, I feel this option should be available to those interested, especially given Cadillac's decision (ill-informed in my opinion) decision not to supply our car with a spare tire.

JFJr
09-01-12, 04:25 PM
Ted, thank you for your dogged determination on this issue. While I do not have a desire for run-flats, I feel this option should be available to those interested, especially given Cadillac's decision (ill-informed in my opinion) decision not to supply our car with a spare tire.Yes it should. For those who use their "V" as a daily driver, travel often in business clothes and drive at night, run-flats provide some peace of mind; and may get you to that meeting without dirty business clothes if you lose air in a tire. I never expected my "V" to be such a comfortable and reliable car, and I do use the extraordinary performance when it's necessary or just for fun.

Jud

Hotrod-Realtor
09-01-12, 08:08 PM
I haven't had but one flat tire while driving, over the last 15 years. Tires today seem to be so much better than the ones my dad use to drive on. For me, I prefer the maximum performance and will take the chance that I won't have another flat for 15 more years.

neuronbob
09-01-12, 09:27 PM
In the same time frame you describe, I have had three flats and a sidewall bubble. I have recounted several times my getting a flat in the V during a major snowstorm in early 2010, and having to be towed for a simple flat. That is completely unacceptable in my book. The other times, I changed to a spare and was on my way in 10 minutes.

tedcmiller
09-01-12, 11:17 PM
To neuronbob, there is nothing "dogged" about my comments on the "issue." I am simply giving my opinion. Take it or leave it - I don't care.

From the facts stated in your last post to this thread, it sounds like you could use a set of run-flats.

neuronbob
09-01-12, 11:51 PM
To neuronbob, there is nothing "dogged" about my comments on the "issue." I am simply giving my opinion. Take it or leave it - I don't care.

From the facts stated in your last post to this thread, it sounds like you could use a set of run-flats.

I'm sorry if I offended; I wasn't trying to do that. I was trying to compliment you on your persistence in pursuing runflats for this car. I have found your prior posts on this topic useful.

I think we can both agree that Cadillac should offer a spare or runflats, or both, as options for those who seek them. :thumbsup:

Good night and have a great holiday, everyone!

jzchen
09-02-12, 01:02 AM
Most people ask for the bad news first, so here it is. As far as I know, there is still no one who makes exact replacement tires in run-flats for the 2009 and later CTS-V.

However, the good news is that as long as you are willing to go a little slower, Pirelli makes 19 inch tires in the correct width and aspect ratio for the CTS-V. The Pirelli run-flat front tire (255/40ZR19 on the CTS-V) is a W rated tire which is a little less than the 96Y rated front tires that normally come on the CTS-V. That means your top speed will be limited to 168 mph. Also, although the rear tire (285/35ZR19 on the CTS-V) is not a metric tire, the Pirelli run-flat P285/35ZR19 (99Y) is. So as long as you are able to overlook these differences, Pirelli has run-flat tires for the CTS-V. Both of these run-flat Pirelli tires are P Zero tires (not all P Zero tires are run-flats).

Do people really care that the front tires match the model of the rear? Goodyear Efficient Grip ROF is listed @ tirerack and they are Y rated for the front. There are several to choose from for the rear, including (Y) rating. I will get runflats in the future when I have to change my tires. (It will take a while though before I wear out the original ones.)

thebigjimsho
09-02-12, 03:29 AM
Do people really care that the front tires match the model of the rear? Goodyear Efficient Grip ROF is listed @ tirerack and they are Y rated for the front. There are several to choose from for the rear, including (Y) rating. I will get runflats in the future when I have to change my tires. (It will take a while though before I wear out the original ones.)

Well, this is one of the fastest sedans ever made and among the best handling. If you want to treat it like a ghetto'd up hoopty, have at it.

Mismatching tires will negatively affect handling.

Jinx
09-02-12, 04:23 AM
Goodyear Efficient Grip ROF is listed @ tirerack and they are Y rated for the front.

A low rolling resistance tire is hardly appropriate for the CTS-V. "I want runflats" does not mean "I hate performance and should have bought a Prius."

tedcmiller
09-02-12, 03:50 PM
As thebigjimsho says, mismatched tires will negatively effect the handling of the car. Since Goodyear does not have a run-flat tire for the rear of of the CTS-V, the front and rear tires will be mismatched. Hence his comment about "ghetto'd up hoopty." I too prefer the tires being matched on all four wheels. Hence my comment that no one except Pirelli makes a set of four (front and rear, all P Zero) in run-flats for the CTS-V. That having been said, the rear run-flat in the Pirelli is a P metric and the front is not. Are they mismatched?

To neuronbob, no offense taken.

kenhock
09-03-12, 09:04 AM
an interesting discussion. having experienced a flat on a run flat i definitely liked being able to drive home. what i didn't like was trying to find a replacement set of tires (sts-v's not only have different size front / back, they also have 19" rims on the back, 18" on the front). at the time the pirelli oem's were on back order with no upcoming production date. my first 2 choices of non run flats were also either on back order or couldn't get a matching set. all in all it took 4 1/2 days to get tires in during which time the car sat in my garage. i decided that since sitting that long it was best to have the car towed to the tire shop. the quick flat repair solution that gm now provides appears to provide us the ability to continue to drive the v which is a nice option for those of us who rely on the v as our dd. no one will stock our tire sizes so there will be, at best, a minimum delay in getting back on the road. i like both options; when it comes time to replace the oem's i'll have a tough decision to make.

thebigjimsho
09-03-12, 10:02 AM
If I'm local I just rely on roadside assistance. If I'm traveling I put an old PS2 on one of my track wheels in the trunk.

baabootoo
09-03-12, 12:10 PM
Very nice info, details, and write up. Thanks.

jzchen
09-05-12, 05:02 AM
As thebigjimsho says, mismatched tires will negatively effect the handling of the car. Since Goodyear does not have a run-flat tire for the rear of of the CTS-V, the front and rear tires will be mismatched. Hence his comment about "ghetto'd up hoopty." I too prefer the tires being matched on all four wheels. Hence my comment that no one except Pirelli makes a set of four (front and rear, all P Zero) in run-flats for the CTS-V. That having been said, the rear run-flat in the Pirelli is a P metric and the front is not. Are they mismatched?

To neuronbob, no offense taken.

They are different size tires in the first place. They have different driving dynamics as it is. In dry weather the rear tires have more grip than the narrower front tires. In wet the wider rear tires are more likely to hydroplane. That is why they note on tirerack that sometimes the tread pattern is different than shown depending on tire size. The manufacturer is trying to compensate for this difference. "Ghetto'd up hoopty" may be a concern for resale value and aesthetic purposes, but to those who would really prefer a runflat solution, like me, there is one. I don't think a Y rating with a max speed of 186mph vs (Y) with max speed in excess of 186mph is going to hurt me much. I'm not going to get past 175mph as I understand with my automatic. In fact, making the car more likely to understeer is usually considered easier for novice racers like me to handle than oversteer, if I ever get above 100mph or do some performance driving. It's funny, but I'm more comfortable past 100mph in my wife's 328i than I am in the Caddy. (Someone mentioned a concern about the Goodyear's LRR rating and how that affects performance.)

That being said I have experienced a similar issue to what kenhock mentions, and that is an availability issue. That has been a major problem as reported by many. I got a flat runflat on our Sienna, and Walmart did not have a runflat replacement. I ended up getting a non-runflat temporarily, and it screwed up the passive TPMS on that vehicle.

I just checked the tire pressures in our cars yesterday morning. Boy was it a pain to get out the spares and check them. One thing about carrying a spare is whether or not you actually check its pressure or not. (I check tires every two weeks, but I must confess I do not check the spares very often.) Instead of 60psi a couple were down to 54psi. (I wonder how many people are driving around with a flat spare.) Also, how many times have I seen on the side of the road a trunk unloaded of a whole bunch of stuff as the occupants are trying to change a flat...

Every system has it's ups and downs. I'm just trying to help people decide for themselves which option fits them better.

thebigjimsho
09-05-12, 10:07 AM
Sure, the engineers just made the car and then slapped on tires.


If you think that having a staggered setup is the same thing as having vastly different tires from front to back, then go on thinking that.


Even with a staggered setup, the V is fairly neutral. Gee, how did that happen?

Gary Veeeee
09-05-12, 11:15 AM
Good info here, one question though what kind of mileage can I expect to get out of the factory rubber on 2012 CTS V. ? Do these tires perform at all in snow? I do understand it depends on how you drive the car will greatly influence tire wear, but let's just say my driving style is "moderate performance " . when I was at dealers today I was talking to the parts department and they said the tires on the car run four something in the front and five something in the rear. These run flats are very expensive. I was also thinking about getting a winter set of tires what is recommended and what can I do about the rims can you get steel rims for this ?

thebigjimsho
09-05-12, 02:45 PM
PS2s do not move AT ALL in snow...

JFJr
09-05-12, 03:33 PM
Good info here, one question though what kind of mileage can I expect to get out of the factory rubber on 2012 CTS V?I got a little over 18,000 on my stock tires. After that I bought Bridgestone runflats (they were available then) and got 30,000. I now have Bridgestone S-04's (non-runflat) and expect at least 30,000. I try to avoid laying rubber, but don't drive like grandma either. It would be nice if Michelin made their new Super Sports in our sizes. Aren't there other super sedans that have the same tire sizes, front and rear, and if so are the economics bad enough for Michelin that they aren't being short-sighted?

Jud

JimmyH
09-05-12, 08:10 PM
If I'm local I just rely on roadside assistance. If I'm traveling I put an old PS2 on one of my track wheels in the trunk.

+1

I had a flat a few months ago. I just used the air compressor in the trunk to fill it up to 45 psi and that got me home. When I go on road trips, I throw one of the wheels from my other set in the trunk. I also do that in the winter, along with two 80lb bags of salt for more weight.

jzchen
09-06-12, 01:22 AM
Sure, the engineers just made the car and then slapped on tires.


If you think that having a staggered setup is the same thing as having vastly different tires from front to back, then go on thinking that.


Even with a staggered setup, the V is fairly neutral. Gee, how did that happen?

No, I didn't mean that they just slapped on tires. Sorry.

Vastly different, I'm not sure. I've never tried them personally. I'll be sure to let people know when/if I do. (My car sits in the garage most of the time. Call me the weirdo that saves them for later. Last I checked it has less than 5k on the ODO.) By the time I need to change them maybe there will be a matching set of runflats in our sizes.

You're right about performance driving. BUT, I don't think I could push the car that much on the street without killing myself, others, or at the least getting a ticket, to tell the difference.

Slap on your spare set of Michelins for the track. There one wouldn't need to worry too much about getting a flat at an inopportune time/place. If I get a flat in the ghetto I'd like to continue driving to another place before having to deal with it, or during other conditions such as in the rain, snow, sleet, hail, dark, etc. Being stuck on the side of the road having to deal with a flat in a fancy car isn't something I'd like to experience. (The V is the most expensive car in our household.) I think I could be completely happy with even overly mismatched tires for the street...