Wheel Offset, wheel other

[as4z]

Looking for info/advice/concerns on changing wheel, particularly relating to offset. It has been almost impossible to get any good answer on this question.

I have a V50 T5 AWD with 17x7 "sculptors." It has 52.5 mm offset. Obviously, the stock wheel/tire (205/50/17) fit perfectly well. One can get Volvo's OEM 18x7.5 wheels "Medea and Medusa," which also have 52.5 mm offset. Because the 18 inch wheels are the correct offset, there is no risk of wear and tear / weight distribution problems because the wheel is still centered the same. But also, because the wheel/tire combo has grown left and right, Volvo recommends steering stops for this 18x7.5 inch combo.

There are aftermarket wheels. People have already installed them: 18x8, 18x7.5, 19x???, etc. Tirerack.com has lots of wheel options for V50/S40 also. Most of these wheels (all of them) do NOT have 52.5 mm offset. Some are 48 mm, some are 45, some are 42, some are even 40 mm. I'm looking at one, for example, that is 17x7.5 (so I can put 225/45/17 tire) with 42 mm offset. With the lowered offset, there should be no problems fitting the wheel/tire in the wheel well area. So fitment is not what I'm worried about.

I'm worried about the risks of moving the center of the wheel outwards. That changes where the weight (and these cars are not light) is centered. It could put stress on the suspension that Volvo did not design in.

So...

How much offset change is reasonable, if any, technically speaking?

Is there a wheel weight that is too LIGHT? One wheel is 18 pounds with the original OEM wheel being 22 pounds, as an example.

Has anyone used an aftermarket wheel/tire combo on a car and had that new combo last for > 100,000 miles (suspension wear and tear question)?

[drdisque]

I generally feel that offsets within 8 mm are fine. Think about how small that difference is its less than 1 cm. As long as fitment isn't an issue, I wouldn't hesitate going with a wheel with a +45 mm offset or so, +42 gets a little hazy. Overall, the lower offset might actually improve handling but make the car's steering feel a little slower. I wouldn't worry about excess stress too much, again 8mm isn't much from a weight/stress standpoint.

Most quality modern wheels seem sufficiently strong for road driving, regardless of weight.