Donut size spare for Prius prime

I have read the gen 3 & 4 are the same. Also that a gen 2 will work on later ones, but you'll probably get a code since it's a little different in diameter.

 

Gen 2 temp spare rim might be the same though?

 

Maybe. I'm about to head to an appointment soon, so I don't have time to look it up right now. I noticed that on a link earlier in this thread to a Toyota dealer's online store that they didn't spell out the size, just the sku number.

 

Lexus' CT200h's donut spare also fits exactly. My wife has that car, and on longer trips with the Prime we just place that in a big plastic bag and stow it behind one of the front seats. Strapping it down with ropes optional but suggested. We totally lucked out not having to find/buy one.

 

p/n for temp spare, that fits 2017 Prime: 42611-47631

Wheel, Spare - Toyota (42611-47631) | Toyota Parts

p/n for temp spare, that fits 2016 Prius: 42611-47631

Wheel, Spare - Toyota (42611-47631) | Toyota Parts

p/n for temp spare, that fits 2010 Prus: 42611-20841

Spare Wheel - Toyota (42611-20841) | Toyota Parts

p/n for temp spare, that fits 2008 Prus: 42611-20841 (same as 3rd gen)

Spare Wheel - Toyota (42611-20841) | Toyota Parts

So 2nd and third gen temp spare rims are the same part no., and Prime and 4th gen Prius also have same part no., different than 2nd/3rd gen. How different is maybe questionable?

 

Since you already bought into that setup, go ahead and use it. Certainly if I or anyone on this forum were stuck on the side of the road, we'd bolt that 23.9" spare up & drive off.

My thinking on fitment is two fold though, my first concern is the almost ~5% overall diameter difference between a 23.9" spare & the OE 25.0" tire. My second concern is equally as important, Spare Tire Load Capacity. A Prius Prime has a 195/65-15 OE tire with a Load Rating of 1356 lbs, this is the number we'll use as our bench mark. A 125/70-17 spare has a load rating of 1653 lbs at 60 psi & a 135/80-16 spare has a load rating of 1819 lbs at 60 psi. Like most of us you're thinking; This is great because both are higher / much higher than the OE tire, BUT...

Not all of us are periodically checking our spare tire psi to make sure they're always at 60 psi, over time these tires are slowly deflating so now their load capacity is not what you'd think. In many cases it's easy for one of these unchecked spare tires to fall well below our OE 1356 lbs load rating bench mark. So when you take all of these factors in, right off the bat the 135/80-16 spare has a cushion of 166 lbs more load carrying capacity when compared to the 125/70-17 spare tire.


Rob43

 

This spare tire size should be the "Go To" size if someone buys the Toyota 42611-47631 wheel.

https://www.tirerack.com/tires/tires.jsp?tireMake=Continental&tireModel=CST+17&partnum=28MR7TEMPV2


Rob43

 

Be careful: the size in that link is T125/80R17. Maybe that is for Prius v, which has a slightly larger OD (Outside Diameter) stock tire?

The stock compact spare tire spec. for 3rd gen is: T135/80D16 101M

(from 2010 Owner's Manual, page 735)

An example:

https://www.tirerack.com/tires/tires.jsp?tireMake=Yokohama&tireModel=Y870B&partnum=38MD6YOTEMP&vehicleSearch=false&fromCompare1=yes

The stock compact spare tire spec. for 4th gen is: T125/70D17 98M

(from 2016 Owner's Manual, page 566)

An example:

https://www.tirerack.com/tires/tires.jsp?tireMake=Yokohama&tireModel=Y870C&partnum=27MD7YOTEMP&vehicleSearch=false&fromCompare1=yes

I think the above explains why there are different rim p/n's 3rd gen vs 4th, btw: while the tire OD is the same (or very close), and the rim bolt pattern, offset etcetera is the same, the rims are for different tires 16" vs 17". I'd suspect either 3rd or 4th gen spare would do.

 

A 125/80-17 is 24.9" overall diameter....

Remember that the Primes OE 195/65-15 tire is 25.0" overall diameter.

So a 125/80-17 is the best match up.


Rob43

 

You're right on all counts. Strange though: the Owner's Manuals say different.

 

What I find even more interesting is:

When you go to Tire Rack & look up 17" (Plus Two) tire sizes for the Prime, TR only lists the 215/45-17. They do not list the 225/45-17 option, or my overall favorite option; the 205/50-17*.


Rob43


* The tire size I personally run.

 

I went to a Toyota Dealer and looked at the 2019 Prius LE. It has a T125/70D17 98M spare on the 42611-47631 wheel. It has OE 195/65-15 tires that are 25.0" overall diameter. The owners manual for the 2019 Prius warns that the car 'may' ride lower after installation of the spare. Attached is a photo of the spare in the 2019 Prius LE.

 

I found this the other day, might be of interest:

 

With the donut, does it fit vertically or horizontally behind the front seats?

I currently drive around with one of my snow rim/tire in the trunk but would buy the donut if I could get it horizontal behind the front seat.

 

Vertically yes for sure, but I doubt it will fit horizontally behind the front seat, unless you means horizontally on the rear seat cushion. Remember that the compact donut tire diameter is pretty close to the full size tire otherwise you will have trouble driving a car with substantially smaller tire on just one corner.

BTW, your full size snow will fit behind the front seat vertically just fine. I carry my full size spare that way all the time. See my comment and photo in this thread: Why does the car come with a jack and other tire changing tools | PriusChat

 

Depends on how tall you are! The front seats in the Prime go way farther back than those in the Gen II. I could not fit a spare of any type between the rear of the driver's seat and the front of the bottom cushion of the rear seat. I'll have to slide the seat forward to "Gen II distance" when I have rear seat passengers.

 

Does the passenger side front seat goes as far back as the driver's power-seat? I know with my full size tire wedged in between back of front passenger seat and folded rear seat with head rest removed, the front passenger seat can not recline as much, but never tested moving the seat backwards. Most of my passengers to date have had no problem sitting on the front passenger seat that way. Of course, if have to move the front seat that far so that you can not even fit a compact spare into the spot, then normal person would not likely to be able to sit on that rear seat with such small leg room. In that case, just put the tire on the seat and strap it down so it won't become a flying object in case of crush.

 

If you plan to carry the spare (especially a full sized one) standing behind the front seat, be aware that that could hinder the seat's ability to absorb impact in a serious rear ender. When we got hit by a 60 mph texter while stopped at a light, our seats went back well beyond 45°. If there was a spare behind the seat, it would not have been able to collapse like that and we'd have experienced a whole lot more impact to our upper bodies. The back seats will, of course compress, but not as easily or as much as air.

You can see in this picture how far back the seats went. I would not want to have had that happen without that shock absorbing capability.

 

And I thought I was unlucky! I'm surprised there wasn't even more damage with a 60 MPH hit on a stopped car. Looks like the design/build kept most of the damage behind the rear seats.

 

The responders were pretty surprised that we got out of the car on our own. I saw him coming at the last split second and just got my foot on the gas. That probably helped a little. He actually bent our traction battery a little.