Spare tire use?
Thread Starter
Safety Car
Joined: Oct 2007
Posts: 4,426
Likes: 229
From: Pennsylvania
Spare tire use?
I never had to use the spare tire from my 85, but I just wondered about it still being able to used if I have 17" ZR1 wheels on the car and the spare is designed to be used with 16" original wheels. Will the size difference create a problem with the positraction 307 rear end? How can it spin two different size wheels at the same time and at the same speed?
Team Owner
Joined: Sep 2003
Posts: 25,389
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I never had to use the spare tire from my 85, but I just wondered about it still being able to used if I have 17" ZR1 wheels on the car and the spare is designed to be used with 16" original wheels. Will the size difference create a problem with the positraction 307 rear end? How can it spin two different size wheels at the same time and at the same speed?
Temporary - to get it "off the hi-way" maybe!
You need to carry maybe an alternate - 12V compressor and maybe some tire plugs! AAA is a good idea or emergency towing/road call on your car insurance!
Melting Slicks
Joined: Mar 2002
Posts: 3,252
Likes: 6
From: The Colony Tx
I used to drive from the DFW to KC area on a very frequent basis, most of the time the drive was late night. If you take the eastern route there isn't much in a lot of places. My thought was if it were a rear tire to take the time and put the spare on the front and then the front tire on the back.
This way you would definately know if there is a problem with the spare as soon as it happens. And for me I would probably slow down just to make sure that if there is a problem I know about it as soon as it occurs.
This way you would definately know if there is a problem with the spare as soon as it happens. And for me I would probably slow down just to make sure that if there is a problem I know about it as soon as it occurs.
Burning Brakes
Joined: Dec 2008
Posts: 1,021
Likes: 7
From: Morgan Hill and Marina California
I never had to use the spare tire from my 85, but I just wondered about it still being able to used if I have 17" ZR1 wheels on the car and the spare is designed to be used with 16" original wheels. Will the size difference create a problem with the positraction 307 rear end? How can it spin two different size wheels at the same time and at the same speed?
How much it cares about tire diameter, I don't know.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
What size are the tires on the car now? If you have 315/35-17 tires on the rear, those tires will not fit in the spare tire carrier, so carry a large 40 gallon plastic trash bag. A 275/40-17 will fit in the carrier with no problem.
The OEM spare will work for going a short distance so you can get repairs. But those tires were never meant for speeds above 50 MPH or for any more weight that what is shown on the door sticker. IIRC, the inflation pressure is about 60 psi.
If the spare is original to a C4. I would really question using it as the compounds would be dried out and flexing from use and heat buildup could destroy the spare.
Also, most people don't check the spare to make sure it's inflated. Once the tire loses all of the air pressure, the tire bead could separate from the wheel. So it's always a good idea to check the spare twice a year.
And for C4 owners who have never used the spare, it's worth the time and effort to simply change a tire using the OEM jack, lug wrench and mount the spare and put a road tire/wheel back in the carrier. There's even a light under the car!! It works with the interior lights.
The OEM spare will work for going a short distance so you can get repairs. But those tires were never meant for speeds above 50 MPH or for any more weight that what is shown on the door sticker. IIRC, the inflation pressure is about 60 psi.
If the spare is original to a C4. I would really question using it as the compounds would be dried out and flexing from use and heat buildup could destroy the spare.
Also, most people don't check the spare to make sure it's inflated. Once the tire loses all of the air pressure, the tire bead could separate from the wheel. So it's always a good idea to check the spare twice a year.
And for C4 owners who have never used the spare, it's worth the time and effort to simply change a tire using the OEM jack, lug wrench and mount the spare and put a road tire/wheel back in the carrier. There's even a light under the car!! It works with the interior lights.
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Thread Starter
Safety Car
Joined: Oct 2007
Posts: 4,426
Likes: 229
From: Pennsylvania
I know that I would never actually use a spare tire that's this old, but I just thought that the positraction rear end would have difficulty trying to compensate for the two different tire/wheel sizes on the same axle at any speed for even a short length of time. I guess I was wrong according to some responses so far. I always carry a tire inflater kit, a AAA card, and a credit card for any roadside problems with any of my cars.
