twinspark

Guys,,,my 2008 C280 came with 225/45 R 17 Michelin primacy as standard. Honestly, i dont think highly of primacy. They might be good when it comes to road noise and lifespan, but when it comes to traction and grip, I don't think it can match pilot sport or P Zero. (now,,i feel that the tail is a bit loose and happy when i take sharp or sudden maneouvers

That said, I have heard that some users changed the size of the rear tyres to 245/40 R17 while maintaining the front on 225/45 R17. Will this really result in better grip and handling in general? or will it only result in increasing fuel consumption?

Also, which brand and model do you recommend for dry conditions? as we dont have much rain in Egypt

twinspark

I need suggestions guys

imboom

It is never really wise to mix tires up unless you have to do it for fiscal or emergency situations. If you have to, try not to mix tread patterns or categorical types(ie. mixing all season and summer performance).

A general rule I remember with previous cars though if you HAVE to mix tires is that you place the lower speed rating in the fronts and higher speed rating ones in the rear. This goes for any axle that is driver, fwd or rwd. The reasoning behind this is that when you drive fast, presumably over the slower speed rating tires, you can have a very snappy oversteer situation. Nothing is worse than having a bad oversteer.

Then again, I've heard some people with RWD cars mix match tires to get a specific handling characteristic. This is good if you have alot of money to spend to test out tires.

08w204

If I have you understood correctly, you are only trying to put wider tires on the rear of your vehicle, but maintaining the same tires on all four corners. The sizes you are talking about are the standard staggered sizes found on the sport models. I'm assuming that you have a lux model instead. I do have the sport with the staggered tires, but I need to warn you that the wider tires require a different sized wheel than the fronts have (wider). The shop that just installed my new tires (Michelin Pilot Sport A/S Plus - love them) didn't realize that the wheels were different widths and called me to the shop because the wider tires won't physically fit onto the front rims.

twinspark

So the 245/40 wont fit on my standard 17" rim? mine is a 2008 C280 Avantgarde
you can take a look at my stock rims by following this link
http://liveimages.redbook.com.au/red...c/MERC1342.jpg

twinspark

I am not planning to change the patterns nor categories...I just want to have wider tyres at the back (245/40 R17 instead of 225/45 R17). All 4 tyres will have same pattern and category though.

Reed19x

Does the luxury/avantgarde come with the same size wheels all the way around? Or are they staggered?

twinspark

No,,they are the same all way round....225/45 R 17 Michellin Pilot Primacy

Glyn M Ruck

The Primacy is crap. Fit Pilot Exalto PE2 or Pilot Sport 2's all round & you will be delighted. If you are short of cash then make sure you have the same tyres across each axle. You can go up 2 tyre sizes fairly safely on the same rim - no more than that. Remember to drop aspect ratio to keep the rolling circumference close to standard. This will make your ride more harsh.

imboom

I don't see why not. It's fine, as long as you keep circumference relatively the same.

whiteongrey

245s need a wider rim. They do enhance traction and handling. I would not put 245s on the existing rim - will not perform properly - 40 series are fairly low profile.

Never mix tires, ratings etc unless is a farm truck.

kevink2

Usually true. So if just the rear tires (and wheels) are made wider, car will see more undesireable understeer, and unless you are a good drifter, net handling performance could be made worse. Likely would need sways and/or springs from a sport model to make wider rear tires work well.