Strange...

[Thunderflight]

While instslling my MBRP cat back exhaust, I removed the spare tire to get some more room to remove old system and I noticed the spare tire is alot different than the other four. I have a 2008 Silverado 4X4 Z71 which I bought new. The differences are as follows:

 

Spare:

P265-70R-17 Goodyear Wrangler AT/S

 

The other four:

P265-65R-18 Bridgestone Dueler A/T

 

Anyone have this problem?

 

There is a big difference and I think it could cause some problems if I had to use this Spare on the truck. Going to call the dealer tomorrow.

 

Thanks,

 

Allan

[dlstewart01]

The out side dia. should be the same. or close enough.

[RyanbabZ71]

This is normal. I have a 17" spare and I have 20" wheels on my Tahoe. They do not match the spare. The overall height of the spare is the same size even though its a different size rim.

[georgecdisc]

I haven't heard of this before. I don't even know what my spare is. Chances are it sounds like someone has a 18" wheel as a spare when they have 17" wheels!

[Thunderflight]

The out side dia. should be the same. or close enough.

With the spare sitting next to the regular tire. The spare looks at least a inch taller.

[RyanbabZ71]

ITS 100% NORMAL! GM HAS DONE THIS FOR SOME TIME!

[Thunderflight]

ITS 100% NORMAL! GM HAS DONE THIS FOR SOME TIME!

Won't this possibly mess with the limited slip rear end?

[RyanbabZ71]

Stock Tire >Search Tires Tire 1 - 265/70R17 >Search Tires Tire 2 - 265/65R18 >Search Tires

Section Width: - -

Section Width: 10.43 in 265 mm

Section Width: 10.43 in 265 mm

 

Rim Diameter: - -

Rim Diameter: 17 in 431.8 mm

Rim Diameter: 18 in 457.2 mm

 

Rim Width Range:

Rim Width Range: 7 - 9 in

Rim Width Range: 7.5 - 9.5 in

 

Overall Diameter: - -

Overall Diameter: 31.60 in 802.64 mm

Overall Diameter: 31.56 in 801.62 mm

 

Sidewall Height: - -

Sidewall Height: 7.30 in 185.42 mm

Sidewall Height: 6.78 in 172.21 mm

 

Radius: - -

Radius: 15.80 in 401.32 mm

Radius: 15.78 in 400.81 mm

 

Circumference: - -

Circumference: 99.27 in 2521.4 mm

Circumference: 99.14 in 2518.1 mm

 

Revs per Mile: -

Revs per Mile: 658.2

Revs per Mile: 659.0

 

Speedometer1: mph km/h

Speedometer1: mph km/h

 

Speedometer Difference: % Speedometer Difference: %

Diameter Difference: % Diameter Difference: %

[RyanbabZ71]

ITS 100% NORMAL! GM HAS DONE THIS FOR SOME TIME!

Won't this possibly mess with the limited slip rear end?

 

 

No because the overall diameter (see last post) is the same

[Thunderflight]

ITS 100% NORMAL! GM HAS DONE THIS FOR SOME TIME!

Won't this possibly mess with the limited slip rear end?

 

 

No because the overall diameter (see last post) is the same

 

Can't argue with that. Just looks bigger.

 

Thanks

[jwoodall]

All the Silverado's with 18" wheels have 17" spare tires.

[MS3DALE]

GM has been doing this since '04,Heres a bulletin on it....

 

 

Service Information 2005 Chevrolet Chevy K Silverado - 4WD | Sierra, Silverado (VIN C/K) Service Manual | Document ID: 2222571

--------------------------------------------------------------------------------

 

#02-03-10-001D: Spare Tire is a Different Size Than Other Tires - (Jan 12, 2009)

 

 

Subject: Spare Tire is a Different Size than Other Tires

 

 

Models: 2002-2009 Cadillac Escalade Models

 

2000-2009 Chevrolet Suburban, Tahoe

 

2002-2009 Chevrolet Avalanche

 

1999-2007 Chevrolet Silverado (Classic)

 

2001 GMC Sierra C3

 

2001-2009 GMC Yukon Models

 

2002-2009 GMC Sierra Denali

 

1999-2007 GMC Sierra (Classic)

 

 

This bulletin is being issued to supply additional information concerning the spare tire on the above vehicles. You or your customers may have noticed that the spare tire has a 16-inch diameter steel wheel or 17-inch diameter aluminum wheel while the road tires have a 17-inch, 18-inch, 20-inch or 22-inch diameter aluminum wheel. Although the spare tire has a different wheel diameter and may be a different brand, the rolling circumference is nearly identical to the road tires. The size difference will not cause a concern because the spare and the other tires will travel the same distance in one revolution.

 

This combination of non-matching tires is used most often on full-size trucks. These vehicles use a road tire and wheel combination that may be too large to conveniently fit the storage compartment space of the vehicle. The customer may not be able to easily remove the spare tire/wheel from the storage area because of its size and/or weight. A steel spare wheel, rather than an aluminum one, may be used since the spare is stowed under the vehicle where it is exposed to road and weather elements. A steel wheel is less likely to incur cosmetic damage while in the stowed position for long periods of time.

 

Please provide this information to your customers. Also, remind your customers of the importance of following the tire maintenance schedule as listed in their Owner Manual. Additional tire care information can be found by visiting www.gmtiresafety.com or contacting GM toll-free at 1-866-522-0505.

[ryan_hermanutz]

Not to mention it is a spare tire that is only susposed to get you by until you repair/replace the bad tire.

[Visegrip117]

Not to mention it is a spare tire that is only susposed to get you by until you repair/replace the bad tire.

 

 

Yep, not meant for continuous use. Hence the ugly rim

[clemsonblozz]

Not to mention it is a spare tire that is only susposed to get you by until you repair/replace the bad tire.

 

 

Yep, not meant for continuous use. Hence the ugly rim

 

 

 

the spare tire looks taller because it has no weight on it