Mount 17" Wheels? Firestone said absolutely not.

I found a deal on eBay for 17" Scion Tc rims with relatively new tires plus TPMS sensors for $255 + $150 shipping. I patiently waited for them to be delivered and when they came, I looked up the closest tire shop for mounting which happened to be a Firestone shop. I called ahead with the specifics of what I wanted done and they quoted me $40 to mount, balance and transfer my TPMS sensors. An hour after I dropped the car off, I got a call from a service rep. Excited, I thought they were going to tell me they finished the job. Nope, they explained that they called Toyota (why, I have no idea) and Toyota highly discourages mounting wheels bigger than stock. I politely questioned the validity of the recommendation and they emphasized that Toyota said it could damage the hybrid components. I asked one more time if there was anyway they would do it, as I knew others including dealers had done this, but for liability reasons, they said absolutely not. I didn't push the issue further after hearing the word liability and took it down the road to an NTB and they did it without question.

I have read other threads on here of people's experiences with Firestone and hybrids and it bewilders me to think that a national auto care shop in today's day in age refuses or is incapable of touching non-hybrid components of a hybrid vehicle. Granted, I would never let Firestone or anyone other than Toyota touch anything having to do with the HSD, but these were just rims, tires and a commonly found TPMS.

On the other side of this, I have no idea if they called a local dealer or if they consulted with a nation-wide knowledge base, but has anyone else been denied service to mount larger than stock wheels?

Anyways, here's the result. Looks fine to me : ) I've ridden on them for 100 miles with no problems and have been able to keep 55MPG (with a very marginal increase in hypermiling) so far.

 

I was not surprised that they refused after explaining that it was for liability reasons. I didn't push any further after they mentioned the word. There is liability in working with any other car too, but they are prepared for it. I was surprised that they are not prepared to work on a Prius or any other hybrid considering how many are on the road now. The hybrids may have been exotic 4 years ago, but they certainly aren't now. I can't drive a day in Houston without seeing several.

 

Houston is quite warm averaging 70-90 degrees during the day right now. It will be close to 100 degrees if not higher in a month or so. Houston is also very flat. The only hills here are artificial ones.

I was getting about 55-60MPG on the stock 15" with mixed city/highway driving. On the 100 miles that I have driven on the 17", I have avoided the highway completely (which is hard in Houston) and I've marginally increased P&G. I'm getting 55MPG (53-57MPG fluctuation) now, but we'll see how long I can keep it up. I have found that it's not much more difficult building up the mileage, but it definitely drops faster during acceleration or constant speeds.

I will definitely give an update after the tank is done.

 

Not quite sure how to calculate that.

 

I am losing mileage, but it wasn't the 50MPG or below that I was expecting (as I read from some as well). I stored my old tires and rims just in case it didn't work out, but so far I'm fairly content. I definitely am not hitting 60MPG anymore, but I haven't dropped below 53MPG.

Once the tank is up, I'll give an update to see if it's possible to maintain mid-50's MPG with these size wheels. I'm crossing my fingers, 'cause I sure do love the way they look.

 

Sorry to bump this back up, but thought I'd throw in an update on keeping up mileage with 17" wheels.

The end result was 54.6MPG at 527miles. Manual calculations came out to 54MPG. I kept the tires at 40psi all around and the weather was a consistent 75-95 degrees. Considering that I eventually had to take the freeway, let my non-hybrid driving brother borrow my car to haul 50lbs of crawfish no less, and had to blast the A/C with 4 coworkers in the car during this tank, I'm fairly content with the mileage.

When all was done and said, I didn't really P&G much more than before. Houston drivers are quite aggressive so I really only P&G as much as I could before it got annoying to drivers behind me. Though, it did feel like if I hypermilled to an annoying level, 60MPG+ is not out of the question.

I love how my Prius looks with those wheels. The aesthetics seem more balanced now as opposed to before where, to me, it looked like the car was riding on tiny roller skate wheels. There is a slight compromise with ride quality, but the handling has increased greatly. The car points with much more intent now. So if anyone who is achieving mileage in the 50s and is considering bigger wheels, it is possible to keep mileage high without too much extra effort.

Thanks again for the compliments, btw!

Below is the final screen rolling into the gas station. Sorry for the terrible image quality, I took it with the camera on my phone.