Mercedes GLC Forum banner

20 inch tyre exchange

1101 Views 5 Replies 3 Participants Last post by  Benzmann300
I have a 2020 GLC 300 with 20 inch wheels. The ride is too harsh for my liking. Here in Australia the roads are not that great either. I want to do some driving on gravel roads as well. I am planning to change the 255/45/20 to 255/55/20 non run flats. I think this should give a much better ride and a be by more robust tyre for a bit of light off-road driving. I try not avoid buy new rims. Anybody has done something like this??
1 - 6 of 6 Posts
I don't know how it is in Australia but in west Texas you don't want to be without a spare tire. It could take hours for service; you do not want to sit in sun at 100 degrees plus Fahrenheit. I currently have 20inch wheels on a GLC 300 that came with run flat tires. I had to replace them at 20,000(n) miles I replaced them with Michelin Pilot all season tires non run flats. The Michelin performed well double the milage 39,000 miles(y)currently on my second set of Michelin Pilots. I did purchase spare a wheel on eBay. The spare wheel does takes up lots of space I only take it on long trips.
I am also in Australia and have a GLC 300 with the 20 inch wheels and agree the ride is too harsh and noisy on some road. They can be very good on the right surface. Mine are the run flats and was hoping that the non run flats would have been better BUT sounds like that's not the case. More of an issue re the low profile of the tyres than the large diameter rim is the issue.
I am also in Australia and have a GLC 300 with the 20 inch wheels and agree the ride is too harsh and noisy on some road. They can be very good on the right surface. Mine are the run flats and was hoping that the non run flats would have been better BUT sounds like that's not the case. More of an issue re the low profile of the tyres than the large diameter rim is the issue.
Went to a tyre place today and was quoted around low $500 for non runflat 20 inch tyres. Not sure if I should take the risk driving for another 50000km with a marginal improvment in comfort or bite the bullet and buy some smaller rims with new non runflats straight away
Went to a tyre place today and was quoted around low $500 for non runflat 20 inch tyres. Not sure if I should take the risk driving for another 50000km with a marginal improvment in comfort or bite the bullet and buy some smaller rims with new non runflats straight away
Reports of tyre life are that 25000kms could be optimistic so you might not have to wait as long as you think. No spare is a gamble I don't think I can take and I wouldn't like the expense or loss of room has me struggling with non run flats so might just have to continue with a lower tyre pressure to improve the ride a bit and at lease i have become accustom to the noise on certain roads but not a compromise I like.

Your situation travelling off main roads brings up a hole different consideration so I wish you well. If you have the AMG wheels I'm sure they would be sort after as a used item on the market to help the change to something though
Thanks again for your reply, I think I have another 10000 to go on my current Pirellis. In the meantime I will keep my eyes out for some 18 inch rims and will get some 235/60/18 non runflats with either a repair kit or a space saver. That should o the trick. Done something similar to my wife’s 330i and the difference is amazing.. HAPPY NEW YEAR!
  • Like
Reactions: 1
1 - 6 of 6 Posts
Top