I'm interested in replacing the temporary spare with a full size tire. I plan to include the spare in the rotation schedule, increasing the life of my set of tires by 25%. I also find it much more convienient to have the capability of replacing a flat with a tire that will not put the restrictions on driving that the temporary one does.

I checked the shop manuals and found a reference to allowing 5 tire pressure transmitters to be recognized by the tire pressure monitoring system. I plan to replace the temporary spare with a factory Toyota wheel, the tire pressure transmitter, and the same tire already on all four corners.

Loss of some trunk capacity is not a concern.

Can anyone advise me on any concerns or problems with making this switch?

Thanks

Will a full size spare fit in the same spot as the temporary spare? Or did you just plan on keeping it in the trunk?

He did say loss of trunk space is not a concern.

I think it's a bit silly to do IMO. 1st you are now carrying more weight than you normally do. 2) You lost trunk space. 3) Tires wear by age as well as by milage, so you could end up with a tire that is fine but old. 4) Chances of you ever needing a spare are small. If you do use it, it's only temporary until you replace or fix affected tire. In either case, you will need to fix affected tire ASAP.

The temporary spare has the same diameter as the regular tire, but its width is less. So, it should fit into the trunk well, but it will stick up above the trunk floor, reducing the trunk depth available for use.

Stan

You'll have trouble securing it in the trunk too, so plan for some extra banging and noice back there. I tried this in my last car and decided against it in the future.

07 TCH - slightly modified

I doubt a fifth tire will work the way you describe.
I believe tires are no longer 'rotated' around the corners the way they used to be.
Aren't they moved front to back and back to front, keeping them spinning in the same direction?

If so, you would have to buy a PAIR to make your scheme work properly.

If you only bought one, and it was put on the road, it could only be used on that side of the car. You would be 'rotating' three on one side and two on the other.

good point... rotation schedule will be screwed up.

Yes, wear would decrease by around 25%, but cost to replace your tires would increase by around 25%. So in the long run it would be a wash.

<Best Tank Economy!><Best Tank Endurance!>

If you use your spare as part of the rotation, it'll be much more likely to fail in an emergency. It's like dipping into your hidden twinkie stash in non-emergencies. Then in an emergency, all you'll find is a note saying "Future Self, I owe you one twinkie. -Self"