Does everyone ignore this number when they go to a smaller profile bigger tire?

When I called to order some 285/25 20s for my rear tires, they said they didn't have a tire that would be adequate according the load index numbers for the given tire.

 

As long as it's close it's fine. The load indexes specified are very pessimistic and you would probably have to fill your car with 5 adults and a trunk full of lead before it became any kind of problem.

 

That was my contention with the load index. I have seen some boats with the same tires as the ones I was looking at (Chrysler 300 C).

 

i have seen and run tires with not enough load index as well, never had a problem. i can't say it will never have problems, but personally i haven't seen friends with these tires having blow out or related problems

 

I am on 245/30/20's up front and they are not indexed high enough for the load as well. So far so good. Although I did have a set of Falken FK452s that the tread separated on. That was a bit scary.

 

What's the index the car requires (I forget) and what are you planning on using? My tires are 93.

 

93 as well

 

In theory a lower load index tyre should have a slightly higher pressure to compensate.
(The effective load bearing capability of a tyres increases with pressure. Up to a point). Tyres have an easier life at higher pressures and will last longer; with the downside of comfort and perhaps grip.