The walls in a lower speed rated tire are going to be weaker and in my
experience, the car will drive diffrently, feeling as if the tires were
underinflated.

In one case, a minivan, the wheels would touch the pavement on curves.
In another case, a Lexus LS400, the car would just be hard to control
when turning at normal speeds.

Good luck

If you put T rated tires on your Maxima, don't plan on going faster
than 118 mph for a considerable length of time. The tire will blow out
due to overheating. H rated tires can go 130 mph (your Maxima's
governed top speed) all day without any heat issues. Also, as menitoned
in another post, the higher speed rated a tire is, the stiffer the
sidewalls are. The suspension was tuned for H rated tires, so a T rated
tire may have a softer sidewall, therefore a cushier ride, but it won't
be drastically different.

That's really the main issue. Other than that, you're OK.

Here's a list of the speed ratings;

http://www.discounttiredirect.com/direct/brochure/info/tmpInfoSpeedRating.jsp

CD

Are they by law even allowed to sell you tires that don't meet the
recommended speed rating for your vehicle? I would recommend sticking
with what's recommended for your car.

Nirav