Spare tire size with larger tires?

So my question would be how important is the spare tire size to be exactly the same size as the aftermarket tires you are running. These trucks have an open differential which to me would mean as long as it’s close I would say within 2 inches size wise you should be fine as long as you’re not running in four-wheel-drive if you would need to use the spare. Thoughts?
So if you’re gonna do serious off-roading I can understand matching the size but for the normal every day person to me it doesn’t seem as important if it’s just to get you to a repair shop especially for those who run the same size spare but don’t incorporate it in the tire rotation.

 

I think you will be fine with a different size but would not wanna run it for too long and certainly no 4x4.

Its no different than going through a corner, just a really really long corner.

 

Agreed my thoughts exactly.

 

The open diff on modern Toyota's isn't exactly the same experience that most of us are used to on old school trucks. There are other systems (more than the diff itself) that are impacted by tire size. Toyota has integrated AUTO LSD, A-TRAC, and VSC systems on just about all vehicles now. Some of those systems monitor traction performance and apply braking power to individual wheels to mimic a more traditional LSD setup.

Someone smarter than I might be able to weigh in how different tire sizes would impact the Auto LSD, A-TRAC, and VSC systems on the new Toyota's. Maybe it would have no negative impact at all. I'm not sure.

In the end, I think it's just wise to have a matching spare because you never know the situation when you'll need it. It might be that one time you go off-road and you'll need it on the front axle in 4WD. Maybe you'll get a flat in the middle of nowhere and you're 70 miles to the nearest tire shop. You just never know.

Also, you can actually extend the life of your entire set of tires by rotating through 5 tires vs 4. If you're worried about saving money, then get a set your desired set of 4 tires and then just buy a cheap tire (new or used) for the matching spare. You can find halfway decent used tires for about $50-$75 a pop.

 

Sounds good except when Toyo put an 18” spare rim on their trucks with 20” rims all way round. I will keep an eye out for used 20” rims as personally would like same tire on the spare but not sure ordering the OEM plat rim is really called for. Maybe an old one yes but sure new it’s rediculous.

 

I bought 4 aftermarket rims, more offset and larger tires a year ago.

My matching 5th just came in today. I'll put into into the tire rotation as well, to cut down on usage of the main 4 in use.

I didn't want to be stuck on the highway, towing a trailer, with a flat on the front and an odd sized spare.

 

My truck has after market rims and tires. I don’t have a spare so I keep a portable air compressor in my tool box (which is just a large Plano box with other tools in it). I don’t really go anywhere so I’m not too concerned about a flat.

 

Just get something similar in height. That can be had from 17, 18s, and 20s. There has to be an option.

 

No idea what the 3rd gen trucks want in terms of spares, but, from my extensive forum lurking, the 2nd/2.5 gen trucks did not like different sized tires on the drive tires in 2wd because it would trip the traction control when the rear wheels were spinning at different speeds. Most say if you need to run a different size tire, pull one of your front tires and put the spare up front, then put the full size on the rear so you have 2 identical drive tires. Someone needs to be the guinea-pig for the 3rd gen to see if this is still the case.

 

I can say that I had two different sizes on my 2017 Tacoma. Had a blowout on the rear wheel drove for approximately 120 miles with no issues no lights whatsoever. Spare was stock other 4 were 285/75/16
Stock were 265/70/16

 

In the front it would be fine personally if I have a rear flat I would swap a good front tire for the rear then put the spare on the front.

 

That very well could be the case on the tundras as well. I'm just relaying what I have heard around. I'm still on stock suspension and tires size after 10 years so I have zero experience. Back to your first post, I think the worst that can happen is the computer being a little unhappy I don't think that you can do any mechanical damage because everything is open diffs.

 

Got my 5th Black Rhino mounted with a Falken WildPeak 275/70/18 under the truck.

No issues. What a relief to finally have a full matching wheel.