mjmusicpro

Living in Iowa, the width of the tires recommended for the 2008 grand prix GXP, 255-45-18 for the front and 225-50-18 for the rear, creates pretty much a toboggan effect on the snow and ice. I was looking to replace the original with like a 16" wheel and tire. A 195-70-16 on the rear, and a 205-70-16 on the front would give me about the same overall diameter, but would reduce the width by almost a couple of inches, which would definitely give me better traction for the winter months. The dealer says nothing will work but the original equipment size tires, but they definitely are not working. Appreciate any input.

bigalnash

well first off ur dealer is a moron.... you cannot do 16 inches wheels because we have bigger brakes than the other models. the smallest size u could go is 17 inches. and if ur going that route get some comp g wheels hehe

Rare4thgens

Yeah, I think your dealer meant the wheels and the larger brakes. Maybe get some cheap 18 inch wheels for winter with some actual snow tires and go 225 all the way around. I don't think it would be a good idea to try 17s, there is barely room for the calipers now but maybe. If I have to drive mine much this winter, I might do just that. A friend had a comp G Prix with Bonneville GXP wheels, it did fine with all season tires here in Michigan and we get a bit dumped on us ;-).

mjmusicpro

yeah, I forgot all about the monster calipers. Maybe I could just go with a narrower tire in the 18" series. I put on some Goodyear F-1 All Seasons last year , but it was still a little hard to handle. I ended up putting some sand bags in the trunk just to stabilize the rear a little bit which seemed to help the floating effect. Don't really know what to do, just don't want it piled up somewhere due to the lack of control.

StealthV8

iTrader: (1)

there are a lot of gxps using 17" rims in the winter.

SigmaX6

I use 17inch rims off a impala LTZ that i found at a wrecker. Also when u swap rims for winter youll get the tire pressure coming up on your hud cause it cant find the sensors anymore.

mjmusicpro

Do you have a GXP Sigma? What size tires do you put on the 17"? Do you run all the same size or different front to back?

StealthV8

iTrader: (1)

all the guys i know run them all the same size all around

williamGT

iTrader: (5)

I live in Yellowknife NT Canada.....I took my car out 4 times in the winter, and I had no problem with traction.

SigmaX6

i wont need to drive my GXP in winter(manitoba) anymore just picked up a 94 sundance! WOOT

mjmusicpro

Actually after having the strut mounts bored out so I could tilt the rear tires out a little more at the top, the car drives, rides, and handles better than it ever has. GM should do a recall and do this for all the GXP's that need it. Hopefully the better ride will make a difference for the winter. It has got to make it better. Thanks for the advice.

williamGT

iTrader: (5)

Cool. I bet it won't be as fun as my Astro van winter beater...lol

SigmaX6

there a guy around here that has a supercharged astro van he drives all year round lol.

williamGT

iTrader: (5)

sweet...theres a 350 V8 Astro van here in town, I don't see it to much.

lspuck

I ran 17's with 235's all the way around in the GXP last winter, with no problems what so ever. Clearance around the calipers is tights, but theres room. My TMPS was no affected, as the GXP's do not use a traditional valve stem sensor, but rather a sensor built in the the ABS sensor that calculates rotating mass of the wheels or something like that. I bought a wheel/tire combo from tire rack for a pretty decent price. The wheels are Sport Edition F2 (17x7.5) and the tires are Goodyear Ultragrip GW3 234/45/17. Current price on TireRack would be $1,000.00 even (i think i paid a little bit less last year)

But again, you can deffinitely go down to 17's for winter

Ls4GXP

If you want to have a narrower tire for the winters and keep the factory height and the
calibrated correct speed on the HUD then go with a trade, swap your factory 2 8inchers
with 2 7inchers I'm sure there's a lot of guys that live in summer like weather year long on
this board with do that in a heart beat...besides rotating is the biggest bang for your buck.

GXP25

iTrader: (3)

I'd be one of those guys. :waves

I'd definitely like to take them off of your hands. More like I wouldn't mind swapping out my rears (7 inches) for your fronts (8 inches).

Let me know.

EDIT: Nevermind, you have a 2008 (non matching wheels).

Anyone with a set of 2005-(early)2007 GXP front 8 inch wheels that they're willing to sell or trade for my 7 inch rears?

2000blkta

iTrader: (3)

on a related note I have a set of (4) 17" 2004 comp G Prix I'd like to run on my wife's 2008 GXP this winter. Will I need spacers or will they just bolt right on ? I'd like to them with Blizzaks ... with the OEM tires/rims it'll be in the ditch - or worse. Thanks guys