UK 98 A6 Any Problems Replacing 15" wheels with 17" wheels ?

Sucks, doesn't it?

Yes.

Harsher ride. Higher likelihood of bending a rim on a pothole. More expensive tires. That's all I can think of.

Not needed if you select the correct size tire (see link below).

Better/quicker steering response with 17s, although that depends on the type of tire as well.

Generally more grip and better high speed stability assuming you'll choose a wider tire to go with those new larger rims.

Assuming you choose a 17-inch rim with the correct offset and wheel-bolt pattern (5x112) and the correct tire size, there will be no other mods required. However, if you have stock suspension (not lowered), putting on larger rims will make the wheel gap look pretty bad. The gap physically won't get bigger, but it's just an optical illusion caused by more rim and less tire.

Some aftermarket rims will also require centering rings because of different center bore, and new lugbolts. Most reputable rim shops will provide these free of charge when you buy rims from them.

Use this tool to help you select the correct tire size (based on your current size) in order to keep the speedometer error down to a minimum:

Cheers,

Pete

and I thought the speed of a car was taken from a drive shaft within the gear box.........by an electronic sensor. This way tyre size does not come into the equation......or does it.

Bigger wheels with bigger tyres will always cause speedo problems with current technology, the speed is determined by revoloutions of the wheel, be it via the drive shaft or whatever, bigger wheels and incorrect tyre choice will always effect the amount of revolutions the wheel does, and cause the speedo to show a slower speed.

Unless you have a GPS speedo.

What pete said is spot on, you have to lower the sidewall to compansate for the larger diameter wheel, right down the 35 profile tires for 19", the only limiting factor on choosing rims is the "J", this is the diameter width wise, 8J should go on with no problems.

Ron

For example, a 1998 A6 Quattro speedometer expects close to 830 tire revolutions per mile, if it is to be accuarate. Check tire sizes at

to see what this spec is for tires of different size.

You can calculate the speedo error based on the ratio of your chosen tire size to 830. Close enough, anyway.

You will probably need to advise your insurance company, if this is not an Audi spec option - or risk voiding your policy.

A company refused to insure me for not standard alloy wheels (even of the same Audi spec, and supplied by an Audi dealer). Note "refused" - not giving me the option to pay a higher premium.

-- Doug Ramage

Thanks for all the valuable information. I will ask the insurance before doing anything. Stuart

That's a valid point which I forgot to mention. In the US, ins. companies aren't as strict as in Europe.

Also, the US-spec. '98 A6 did not come with 17" rims, not even as an option. This option (17x8 rims with 255/40/17 tires) only became available in 2000 for the A6 4.2Q. Not sure how it was in the UK.

Cheers,

Pete

Costs me 40 quid a year more for 18" wheels with Esure

Ron

BTW Stuart, 17's are a bit small, 18" will look much nicer, a nice set of

18" RS4 replicas look very nice on A6's

Tyres are a little more, around 100 quid each for cheap ones, 17" tyres are abit cheaper, if its a quattro you should see 30k miles from a set of tyres, if you dont drive like a nutter

Ron

30k on a set of (performance) tyres?! My best would be about 20k on Toyo Proxes for my S3. The worst was 6k for a set of front tyres for my Lancia 4x4 (uprated to 250 bhp). :(

-- Doug Ramage

I mean budget tyres, and an s3 would be too quick to be driven slow :) I would prob see 10k on a set lol

most high end car manuf. compensate for this and the speedo is a little underrated or slow for bigger tires