Tires: Tire Load Rating on F350, rim width, tire place

Question
Sir,

I have a 2003 F-350 crew cab and I am looking at buying new tires.  The local tire place told me that the minimum load rating is "E".  My problem is that I want to put on 33x12.50x16 and I am having a hard time finding agressive tires with that load rating.  What I am finding are load rating "D" and I am wondering why I can't put on tires with this load rating.  I have a lift kit so they should fit.  Am taking a risk by putting on a lower rating?  I really don't use the truck for heavy loads or heavy towing.

Answer
Chris,

There are 2 issues here:

1)  The width of the rim:  A 33X12.50R16LT requires a minimum rim width of 8 1/2", so you can't use the stock 7" rims.

2)  Load capacity:  This is not the same thing as load rating (which is a tire sizing type of thing).  What you proposed is going to REDUCE the load capacity of the tires and that is never a good thing.

If I have this right, your vehicle came with LT285/75R16 LR E on 7" rims inflated to 75 front and 80 rear.  Please check your vehicle placard, which should be on the driver's doorpost near the bottom to make sure this is correct.

If this information is correct, unless you change rims, you can't change tire size.