GS 450h 2012 wheel size change

[Stevebrooks]

I have a 2012 GS450h fitted with 18 inch alloys (standard). Can I swap these for 17 inch alloys with the appropriate higher profile tyres to give a softer ride? 

[AmbroseJohn]

Brake caliper clearance may be an issue.

[Britprius]

As john above says caliper clearance may be an issue, but judging by the clearance on my car I think it entirely possible. The actual reduction in radius is only half an inch, and I think the non hybrid version uses 17 inch wheels.

John.

[AmbroseJohn]

8 minutes ago, Britprius said:

As john above says caliper clearance may be an issue, but judging by the clearance on my car I think it entirely possible. The actual reduction in radius is only half an inch, and I think the non hybrid version uses 17 inch wheels.

John.

I was going to change for the same reason. I found a new set of 17 inch on eBay but the dealer said they wouldn't fit because of clearance issues. Try taping a length of 1/2 wood across the rim and spin it.

[Britprius]

5 minutes ago, AmbroseJohn said:

I was going to change for the same reason. I found a new set of 17 inch on ebay but the dealer said they wouldn't fit because of clearance issues. Try taping a length of 1/2 wood across the rim and spin it.

That's a good idea john. I know some cars have minimal clearance. My Prius once had the wheels balanced at Quickfit "never again" on backing the car out of the bay both rear wheels locked up. There was not enough room between the wheel and caliper for the stick on weights.

John

[Stevebrooks]

Thanks for the comments everyone. I have seen adverts on eBay where the sellers say the 17 inch wheels fit GS450h's but I've not yet heard from anyone who has actually done it. I am aware the calipers may be the problem; my brother had an old IS200 and changed the wheels for larger ones with low profile tyres. They were such a tight fit he always had to use half worn brake pads otherwise the calipers touched the rims! He did this for 12 years!

[Chris111]

3 hours ago, Stevebrooks said:

I have seen adverts on Ebay where the sellers say the 17 inch wheels fit GS450h's

Do you have the current GS (Mk 4) model or the Mk 3? I only ask as after the final facelift on the MK 3 cars from 2010 some of the SE spec cars came with 17" wheels as standard, whereas prior to this they had all been 18" for all spec models, so if you have a Mk 3, 17" wheels will fit. However, as far as I am aware, all Mk 4 GS cars run on 18" wheels (or 19" in the case of the F Sport) so I'm not sure if 17" would fit. Have you asked your Lexus dealer? You should get a straight yes or no answer then.

[Farqui]

An interesting question, I've just punched in my model/year into a couple of random alloy suppliers and they show a number of 17" options;

https://www.performancealloys.com/alloy-search-results.aspx?ChassisID=11998

https://www.wheelbasealloys.com/alloy-wheels/lexus/gs-450h/2006-present/17-inch

So it looks like you'll be okay with any options listed. Maybe give them a call and raise your concerns, especially if placing an order.

Be careful going with your own offset choices as you might find clearance issues with some of the wheels designs, typically the spoke catching the caliper.

[Chris111]

1 hour ago, Farqui said:

An interesting question, I've just punched in my model/year into a couple of random alloy suppliers and they show a number of 17" options;

https://www.performancealloys.com/alloy-search-results.aspx?ChassisID=11998

https://www.wheelbasealloys.com/alloy-wheels/lexus/gs-450h/2006-present/17-inch

So it looks like you'll be okay with any options listed. Maybe give them a call and raise your concerns, especially if placing an order.

Be careful going with your own offset choices as you might find clearance issues with some of the wheels designs, typically the spoke catching the caliper.

I personally wouldn't use wheelbasealloys for advice. In my experience, to put it bluntly, they don't know what they are talking about. I changed the alloys on my car because of the corrosion to the standard wheels. I chose a set of GMP Italia EGO wheels in the same 8x18 size. However, when I tried to buy them from wheelbasealloys I asked if the standard tyre pressure sensors would fit them. Three days later they emailed me to say that the manufacturer states they won't fit and then they tried to sell me a very expensive kit from themselves. I declined! I then contacted performancealloys about the same wheels with the same question about the sensors. Within half an hour they forwarded me an email they had received from GMP Italia stating the standard sensors would fit with no problems but advised that the offset should be 35 for their wheels rather than the 45 of the standard ones. I had a few more questions and each time had a very quick response. I would recommend performancealloys but I would advise again if you have a Mk 4 ask your local dealer.

I note the OP wants to reduce the wheel size in order to fit higher profile tyres for a more comfortable ride. It is worth noting that, excluding the F Sport, the standard tyre size for the Mk 4 GS is 235/45 18 whereas for the Mk 3 with 18" wheels it is 245/40 so the Mk 4 already runs on a slightly higher profile tyre.

[Stevebrooks]

Thanks for the replies. I think  I'll ask Lexus themselves for advice. And as you say Farqui I will not rely on the advice of a third party who is likely to be more interested in selling me some wheels rather than giving accurate advice. It seems there is a lot of room for error there regarding mk3 and mk4 / rim width / rim diameter / caliper issues / tyre size etc. If I get a difinitive answer I'll post it on here for others to see. 

[Stevebrooks]

I have asked a Lexus technician and it looks unlikely a 17inch wheel will fit my 2012 GS450h Premier with 18inch std wheels. The front calipers are very close to the standard wheels. Thanks for your comments everyone. 

I wanted the softer ride, but it was me being a bit too fussy! I had done the same with my Mondeo changing from 18in to 16in and the ride difference was remarkable. The ride in the Lexus is afterall very comfortable anyway.