Effect of Temporary Spare on Traction Control?

After you put the new tires on did the power/traction system problem go away?

 

I don't know how the TC is affected by the spare un-tire, but that little thing is supposed to be used only to get you to a service station where you can get the real tire repaired or replaced.

It's too bad your wife let the tire store people sell her a whole new set rather than just having them patch the nail hole.

 

Please read your manual. It clearly states "when you must use the temporary spare, never exceed 50 MPH (80 km/hr), and whenever possible, use the temporary spare on the rear (swap a "standard size" rear wheel to the front if necessary)."

The temporary spare has much less traction than a standard size tire, is a bit smaller in diameter (meaning it responds more violently to potholes and other road imperfections), and has lower load carrying capacity than a standard sized tire.
So you use it on the rear where there is less weight on each tire, and where there is less power applied to the pavement, in braking, cornering, and acceleration.

 

Thats a great piece of advice, David. I hope a lot of our fellow Prius Drivers read it.

 

No fair reading the manual! We could all be experts if we did that. I consider it cheating.

Tom

 

I also had the exact same thing happen last night on my 2008 Prius. After I got a flat tire from a screw on the road, I put the spare tire on my right front I noticed the traction control light coming on and off. The car had no power and I had to drive 100 miles to home because nothing was open. I was able to go highway speed and even made it over a hill. After I get the tire repaired it should run fine again. Nice to know it happened to someone else and is not another problem. By the way since the Prius is a very heavy car because of the heavy batteries, it was a strain to jack the car up with the scissors jack.

 

Sounds like the spare tire is not the same diameter as the factory tires. That would definitely play havoc with the traction control(more so as speeds increase). The TC looks at the speed difference in the tires. If the spare is not rotating as fast because it's a smaller diameter, it would look like the other 3 wheels are spinning to the TC...

Levi

 

I had occasion to use the temp spare on the RF tire position and drove the car at 50+ mph speeds. The traction control light did not appear.

I suggest that those owners who see the light appear should check inflation pressure on the spare. Spec is 60 psi.

It is probably unrealistic to expect the average owner to be able to move the spare to a rear tire position, if a front tire had failed.

 

I agree, but sadly most won't take the extra time, or don't think about it because they're frustrated and angry. When a front tire is flat, it's easy enough to raise the rear tire on the flat's side, replace it with the spare, then replace the flat with the rear tire.

 

I wasn't able to stay above 55 or so with my spare on front... On rear it's much faster... (highway speeds)

The car did seem quicker with the spare on. I found myself wondering what it would be like to ride on 4 spares pumped up to max psi...

 

Just curious if any of you know whether the Gen 2's came with 2 different spare sizes. I'm curious because I have a Touring model but use 15" regular version wheels in the winter so I'm curious if I should be looking to replace the spare in the winter time as well

 

I think you'd be fine for a short distance on the front but better yet just make sure the spare ends up on a rear wheel.

If you really want to know, just google tire size calculator(the Miata one always popped up last I knew and worked well). Enter the sizes of your summer, winter and spare and compare the size/speed differences to see you're looking at.

Levi

 

Thanks Levi, actually I didn't think of doing that so for anyone searching:

Specification -Sidewall- Radius - Diameter- Circumference -Revs/Mile -Difference
195/55-16 -4.2in -12.2in -24.4in -76.8in -825 -0.0%
185/65-15 -4.7in -12.2in -24.5in -76.9in -824 -0.1%

 

I thought the compact spare was supposed to be the same diameter as the regular tire for this very reason (as well as the differential being strained if one wheel was constantly rotating at a faster rate). Anyone know the diameter of the compact spare?

 

What ends up happening to fix it