Cadillac CTS donut for a spare?
 

Hey guys. I'm new to this forum and searching for a little advice re: tires. I have a 2004 base with (surprise!) very bald rear tires. As a first time Corvette owner, I am just now learning of the ridiculous price of replacement Eagle F1 EMT run-flats, and I quite honestly can't afford to shell out $600 per tire. Can anyone tell me if a donut for a 2008-15 Cadillac CTS (T135/70R18) will work as a spare if I decide to go with regular tires? I'm pretty sure it'd fit in the main cargo compartment (where the CD changer is), but I'm not sure about lug-bolt pattern, brake clearance, ground clearance, etc. Any advice would be most appreciated. Thanks!

https://cimg0.ibsrv.net/gimg/www.cor...49329c259c.jpg
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Welcome to the forum! I'm not sure on the CTS spare size but my hinch is that it wodul work.

Another option is to spring for a set up like the Z06 guys have. The Z06 does not have a spare and does not use run flats, however they come with a "kit" that has a tire inflate and what amounts to a can of "fix a flat." This is pretty compact and fits in the rear storage compartment area.

https://www.google.com/search?q=c5+c...72822609820076

I don't run run flats on my 2000 but I do carry a small air compressor and a can of "fix a flat" in the trunk compartments

I also have the sealant can and mini inflator. Also have a tire ream and plug kit. However, there are some flats none of the above will fix. So I also carry road service. OP-You'll find few proponents of run flats here. I personally would never run them again. They DO have a place. For instance? How about this; you and the wife take the Vette to a relatives wedding, and get a flat tire. Odds are mighty good it wont matter if you have runflats. However, if you dont have runflats, odds are mighty good youll miss the wedding!! If I was going to run runflats again, they wouldn't be Goodyears. My opinion......

+1 for switching to non-runflats. No need to carry a spare. You can get a small air compressor from Amazon for $20. Combine that with a tire repair kit, and a AAA membership. This will will by far be your best option. The cheaper non-runflat tires are just plain better as well. They are quieter, get better traction, and offer a better ride. I really wouldn't bother with a spare.

Also...Welcome to the forum!!
Don't forget to SAVE THE WAVE!!:seeya

First off, the newer runflat tires are much improved over tires that were available years ago. They ride better, have less road noise and the performance is very good. I would agree that $600/tire is nuts (not sure where you are finding tires that cost that much), but a good quality set of all season runflats does not run anywhere near that price. Tire Rack has Michelin Pilot Sport A/S 3+ ZP tires in stock sizes for $273 each front and $379 each rears. I run these tires on my C7 and they are excellent. And the web site shows them to be in stock. Other sites may show similar costs and availability.

That said, I ran non-runflats on my last two C5s for many years and was pleased with them too. I used Hankook Ventus V12 EVO tires and yes, they were cheaper to purchase than the runflats. I did carry an air compressor and plug kit in the car and had emergency road service on the car as a safety measure.

Bottom line is it is your choice what type of tire you go with but don’t discount the capabilities of today’s runflat tires.

The problem with carrying a spare in a C5, especially a coupe...
...is securing it. AND the jack that you will be carrying. In an accident the spare and the jack can and very likely will kill or maim you.

It's best just to carry a patch kit and a small inflator. That's what most of us do.

The $600/each price is for the Eagle F1 EMTs that the car presumably rolled out of the dealership with. I assume they're discontinued and thus expensive when you find them. I know virtually nothing about run-flats - I've never had them on any of my cars. But in the back of my mind, I can practically hear my father's voice admonishing me that it's a bad idea to run around with no spare. But it looks like I came to the right place. If it's common practice to run normal tires and just keep a compressor and fix a flat in one of the storage compartments, maybe I'll give it a go. I read somewhere that the Caddy CTS donut would fit a C5, but I'm not entirely sure that's true anyway. Thanks everyone for the advice!

The spare wheel discussion has been on the forum for years, many using the previous generation GTO mini spare (with modifications). Found an recent thread from last year, check post #2 for a interesting alternative

https://www.corvetteforum.com/forums...es-fit-c5.html

Modernspare.com. As mentioned figure out a way to secure it safely.
https://cimg1.ibsrv.net/gimg/www.cor...f3fcb3176f.jpg

90% of tire issues occur in the last 10% of tread life — or so I’ve read. The best defense against tire problems is good tires with thick treads. And maybe a AAA card.

Thanks for pointing that out. Sorry about posting a new thread about a topic that's been thoroughly covered. I wasn't really sure where to start.

An update for anyone who is interested: After what I can only describe as a comedy of errors attempting to purchase tires on eBay, I made a 2nd attempt on Tire Rack. By default, Tire Rack wants to know the year, make and model of the car you're buying tires for. But since the C5 has different sizes for front and rear (and Tire Rack wants to sell you 4 tires), my choices were very limited until I switched to providing only the tire size I was looking for - and then I ran into a bit of luck! They happened to have Bridgestone Potenza RE050A RFT's in the correct size on sale for $160/each. Quite the price improvement over the Eagle F1 run-flats (though they don't exactly get rave reviews online). If anyone reading this happens to have any experience with Potenza RFTs, I'd be interested to know what your opinion of them is.

Anyway, thanks everybody for taking the time to educate me on the subject!

New tires much better than 2 spares. Nobody mentioned that above.