Tires: Can I use regular tires instead of XL?, 9 passenger van, wheel position


Question
On the door of my 96 Ford E series Van, it gives the tire numbers P235/75R15XL.
I have some almost new P235/75R15's that I cannabalized from another van (dodge) that went to the great beyond when it no longer could pass smog.
Can I use these tires on my Ford van? They are both 1/2 ton vans.
Some additional info:
I was ready to just use them, then had a blow-out, on a 4700 mile/1 month vacation at 78 mph. and lost all the tread on the front right, the air held and all went okay even though there was some damage to the front/side of the vehicle. The existing tires on this new to me/used van are load range C, the spare is marked M+S (mud and snow) and says extra load.
What do I need to look for/get as to load range? The door info also says 7000lb 3600lb on the front axle and 3800lb on the back, yet it might be important to note that I took this 96 Ford Chateau 9 passenger van (took out all the seats except driver/passenger) and converted it to a camping/rv with bed and tv, it's loaded with stuff and kayaks on top.  

Answer
Roger,

The first thing you need to do is weigh the van fully loaded - everything you would ever think about carrying, full of fuel, water, whatever.  Weigh it by wheel position if you can, but by axle at the very least.  Then compare your values to the GAWR's.  If you didn't weigh each wheel position deduct 10% from the GAWR.

The GAWR is the absolute maximum the vehicle can weigh by position.  If you exceed that (including the 10%, if you did that), then everything I'm about to tell you is wrong!!!

The tires must be the P235/75R15 and Extra Load (108 Load Index)

The Load Range C tires are not the right tires for your vehicle because the require 20 psi more than what is written on the placard.

It is a little confusing about which tires are which, but while you are at it, look at the tires and see how old they are.  Tires that are 6 years or older are suspect.