Important Information Re: 16" Spare Tire

[Bigredz-66]

Check your spare tire!! Just had a defective 17" Wrangler HP. Went to Goodyear, and they were going to place the spare on the ground, however Chevrolet equiped the AV with 16" Firestone Wilderness AT's. Chevy considers this acceptable and will not replace with a 17" tire, even though through the Z-66 package an extra charge was for 17" wheels and tires and charged more for OWL 17".

 

[Dali555]

Yep, been there done that. I while back I posted that we all call Chevy and complain. If we got enough people they might put out a TSB on that and change it. Not too many people responded..... so I gave up.
Marc

 

[ygmn]

This is listed on all the paperwork (owners manual and sticker) for the AVY....and should not be a surprize.....there are several threads on this subject too......

Most have bought a single wheel and tire to match......

 

[corvettejoe]

Why would GM do that? Would it not be just as easy to put a 17 spare on the truck as it is to put a 16? Especialy if we paid for the 17 option...


So we are supose to wobble our way home. Thats really safe.

At leas it aint a dog nut. Heck my vette does not even have a spare. I get run graps with it.

 

[RichUF]

A couple of things are clear to me...

1) No one purchased a matching 17" alloy spare wheel and matching tire for their Av because it is NOT AVAILABLE.

2) I agree with GM that the STANDARD SPARE wheel/tire provided is safe as a temporary substitute as it has nearly the same OD as the 17" combo. As a bonus, it's probably rated for more than 45mph for extended period of time.

This issue just never bothered me really. JMO.

Rich

 

[DougD]

Why would GM do that? Would it not be just as easy to put a 17 spare on the truck as it is to put a 16? Especialy if we paid for the 17 option...


So we are supose to wobble our way home. Thats really safe.

At leas it aint a dog nut. Heck my vette does not even have a spare. I get run graps with it.

Simple matter of economics. The stamped steel wheel and Firestone probably saves GM $3-4 per vehicle, across the board for most of the truck line.

Also, the overall height of the complete assembly is not significantly different than the 17 already on the vehicle, thus there won't be a tremendous "wobbling home" issue.

 

[brheas]

As others have said, it is just a "spare", meant for temporary use while you get your other tire fixed. It is much better then having a "space saver" spare isn't it? (there is always a bright side). GM is not the only manufacturer that does this.

 

[BBlueAV]

As others have said, it is just a "spare", meant for temporary use while you get your other tire fixed. It is much better then having a "space saver" spare isn't it? (there is always a bright side). GM is not the only manufacturer that does this.

I concur. Having used it, I found no problems at all with wobbling or handling. I fixed the flat tire, put it back on, put the spare back under the truck and went on my way. This is not a safety problem/issue and works much better than those stupid 'mini-spares'. I certainly would have liked a matching wheel and tire to allow for a 5-tire rotation; however, see why the general (and other manufacturers) do this. A buck saved here and there can make up a lot over all the vehicles they sell.

My .02

BBlueAV

 

[ygmn]

The spare has same OD as Z71 and Z66 tires......Heck the spare tire size is same as base AVy 16" wheel setup....

I bet GM saves about $100 per truck.....using this verus adding another 17" alloy wheel with premium tire.....


To find another...check our parts for sale section and/or ebay...people who have changed wheels are selling them.....as knock offs....

HTH

 

[ShapeShifter]

Another concern: in some areas of the country (like here) alloy wheels take a beating with snow and salt, and will corrode quickly if not washed and maintained often. While it could be nice to have a matching wheel for a five tire rotation, unless you got underneath your truck and periodically scrubbed your wheel, I wonder how long it would last until it started to look pretty bad.

Of course, in other parts of the country, this may not be such an issue.

A couple of things are clear to me...

1) No one purchased a matching 17" alloy spare wheel and matching tire for their Av because it is NOT AVAILABLE.

Maybe not from the dealuer, but they routinely show up at places like eBay. Someone gets a new truck, and the first thing they do is put on a set of Dubs or maybe swamper off road tires. The stock wheels and tires then end up for sale. Sometimes they will break up the set and sell them one at a time, other times a member has bought all four, used one as a spare, and then sold the other three one at a time.

If you are determined to have a matching spare, it can be done.

-- SS

Oops, ygmn beat me to it... this time.

 

[ygmn]

-- SS

Oops, ygmn beat me to it... this time.

YEAH baby


HEHEHEHE

 

[DougD]

The spare has same OD as Z71 and Z66 tires......Heck the spare tire size is same as base AVy 16" wheel setup....

I bet GM saves about $100 per truck.....using this verus adding another 17" alloy wheel with premium tire.....


To find another...check our parts for sale section and/or ebay...people who have changed wheels are selling them.....as knock offs....

HTH

Not close to $100, can't be. GM pays ridiculously low sums for the bulk they are getting items in for production itself.

But every penny magnifies across the line and counts, look at the feature reductions from 02-03-04

 

[ygmn]

FYI

Gm pays about $9-15 for the throttle pedals......this price is delivered to GM warehousing....

for the tire it is based on the spare tire used is a temp tire so very cheap.......and the difference in the wheel alloy versus stamped steel.....and that the spare is used on just about all the trucks...where as the alloy wheel is only on the AVY......burbs and rados have different alloy wheels......

I may be off but it is a lot more then the $3-4...based on my experience quoting stuff to GM world wide purchasing.....

 

[03-Z71]

Same here. Just checked my spare on my 03-Z71. I have a
16" Bridgestone Dueler M+S on a black rim. I like it because it's a saftey reminder:
1. It will make us get our flat tire fixed ASAP because we don't
want people to see our AV's with that spare on it.
2. If you don't get it fixed ASAP you will be reminded to get it fixed
evertime you look at it.
If it had the same rim and tire as the rest how many people might forget to get the flat tire fixed? You would change the flat, put it back under the truck and continue on your way. Out of sight out of mind untill you get another flat and then you would remember that you had to get it fixed ....Hello road side assistance

 

[dragoneye42]

Just bought an '04 Av Z71. Was looking at the spare and noticed that it was a different brand tire than what was on the 17 inch wheel (Dueller vice Wrangler)...anyway then I noticed it was a 16 inch rim on the spare...Is this correct?? Should I go back and Female Dog to the dealer and try to get a 17 w/ a Wrangler tire?
Reason I ask is because if I am Off-roading and I get a flat wouldnt the geometry be off with the spare on?? Maybe I am wrong...Let me know cause I might not even know what I am talking about

Thanks for any guidance here

 

[I CHNGE]

Just bought an '04 Av Z71. Was looking at the spare and noticed that it was a different brand tire than what was on the 17 inch wheel (Dueller vice Wrangler)...anyway then I noticed it was a 16 inch rim on the spare...Is this correct?? Should I go back and beotch to the dealer and try to get a 17 w/ a Wrangler tire?
Reason I ask is because if I am Off-roading and I get a flat wouldnt the geometry be off with the spare on?? Maybe I am wrong...Let me know cause I might not even know what I am talking about

Thanks for any guidance here

This issue has been covered to death...,your spare is a 265/75/16.
Your tires are 265/70/17

The aspect ratio makes the spare witin 1/10 of an inch the size of the ones on the road=no problemo and Chevy won't do squat about it.

Welcome to CAFCNA you are gonna love it here

 

[RichUF]

Welcome!

Since we have yet another thread about this, and I just went through driving on the spare for 500 miles after shredding one of my stock Wranglers (POS, IMHO), I'll go ahead and write a follow-up question that has also likely been covered already...

If/when I put 285/70/17's on my Z71, I guess I'm going to need to upsized my 16" spare tire, too. Correct?

 

[ygmn]

The above 2 said it well......

IF interested you may want to look in this Q&A section to find what others said about the 16" spare ...also in the 4wd section are some threads about what happens when in 4wd with spare on....

HTH and welcome to the club

 

[RichUF]

The advanced search is not working on my end right now.

I've done a little reading about how differentials work, and I can't seem to get a grasp on why it matters that one tire is substantially larger than another when on the highway (say in an emergency situation where you have to drive a long way on a mis-matched spare). That's the whole purpose of a differential (spinning at different speeds) right?

Could someone contribute to my education in this area please?

 

[ygmn]

The advanced search is not working on my end right now.

I've done a little reading about how differentials work, and I can't seem to get a grasp on why it matters that one tire is substantially larger than another when on the highway (say in an emergency situation where you have to drive a long way on a mis-matched spare). That's the whole purpose of a differential (spinning at different speeds) right?

Could someone contribute to my education in this area please?

the trucks have lockers......and this is the concern....since for speeds under 20 mph the locker will lock when a 100 rpm wheel speed difference exists....and with a larger difference in tire diameter this can occur...which would not be very good for anything..as the big tire would chirp and spin...or the truck would want to go towards the smaller tire side....

HTH

 

[RichUF]

boy, you're making me work for this. Now I'm going to have to dig deep in my brain and try to recall how to calculate the max. difference in tire height that I can go before hitting the 100 rpm difference threshold.

Thanks for the response...makes sense. Didn't think about the locker as being the concern (couldn't imagine that much of a rotational difference).

 

[Tree_Hugger]

The advanced search is not working on my end right now.

I've done a little reading about how differentials work, and I can't seem to get a grasp on why it matters that one tire is substantially larger than another when on the highway (say in an emergency situation where you have to drive a long way on a mis-matched spare). That's the whole purpose of a differential (spinning at different speeds) right?

Could someone contribute to my education in this area please?

the trucks have lockers......and this is the concern....since for speeds under 20 mph the locker will lock when a 100 rpm wheel speed difference exists....and with a larger difference in tire diameter this can occur...which would not be very good for anything..as the big tire would chirp and spin...or the truck would want to go towards the smaller tire side....

HTH

Yes that's a potential problem, but even vehicles without lockers have strict limitations on different diameter tire use.
The universal problem is heat.
A differential generates a substantial amount of heat when it's 'differentialling', normally this doesn't matter, since it doesn't do it for long and then has a long time to dissipate any heat build up. But continuous 'differentialling' doesn't allow the dissipation. Fifty miles at fifty miles per hour of that, and you are really 'pushing the envelope', damage and/or failure will occur soon after that.

 

[ygmn]

Well rpm diffy depends on od size and tire flex....

 

[RichUF]

Yes that's a potential problem, but even vehicles without lockers have strict limitations on different diameter tire use.

Thanks TreeHugger. I guess the real question is what is this "strict limitation" for the Avalanche?

I don't think I'm worried about the difference between a new 265/70/17 that I'm getting ready to have put on and a 1/2-worn one, but maybe I should be concerned about the difference between my stock spare and the 285's that I want to put on in the future

YGMN, If I get around to trying to calc it, I think I'll have to ignore tire flex. I'm good at math, but not that good.

 

[ygmn]

YGMN, If I get around to trying to calc it, I think I'll have to ignore tire flex. I'm good at math, but not that good.

hehehehe.....it is nothing other then less then theoretical Radius but is dependant on air pressure and any possible ambient temp change and possible atmospheric pressure change along with altitude changes etc etc etc...


HEHEHEHE

bust out the HP calculator heheheh