Yeah I have 35% on my fronts and its lighter then the backs. I keep thinking about doing another layer of 20 over the back glass to help darken it all in.
20% on my trucks matched perfectly. On the crew I wanted to go darker so the 5% over the factory rear tint didn't match the front. I peeled the fronts and had them redone in 5% also. It's like a cave now.
If your 20% metered at 13% either you don't have 20% or the cops meter is wrong. There is only supposed to be a 3% margin of error in the meter per GA law anyway.
tint is over 2 1/2 years old, could possibly be 15% I just always figured it was 20% by comparing it to others. meter could be wrong to anything under 70% is illegal here
In NY, anything under 70 is illegal. I had 18 which I just removed after being hassled a lot lately. But it was the first time in 4 years of driving tinted trucks to get shit for it