AH64ID wrote:
Side to side gap can and will be slightly different, but should be very close in a static environment. The only real reason it would be different is misalignment or a severe different in weight from side to side.
Weight has little effect other that an accelerated wear evenly cross the tread profile. Misalignment causes uneven tread wear on the tread profile.
If you measure the trade depth across the tread and it is even across the tread you do not have an alignment problem.
A tread gauge is always in my glovebox, it's a good tool when your shopping for tires of any sort. I check the tread depth in comparison to the makers claims.