I got the truck with only one key and it looks pretty normal, no buttons or anything else on it, just a vanilla key.
Did ALL 2008 XL Rangers have the PATs keys? My truck is really vanilla, just like I like them, crank up windows, stick shift, small engine, single cab. Much less to go wrong......

 

If the key is all metal, you don't. If there's a blob of plastic on it, there's where the transponder is.

If you only have one key, have a 'service' key made. This will be the $3 plain-jane key with no electronics. You should have one for, if nothing else, manually unlocking the door. If the truck starts with this key, you don't have PATS. If it doesn't, you'll need to wait an hour or two for the PATS to reset so your original key will start it up. So don't do this unless you have the hour or two and you don't need to start it.

 

OK, my key has plastic handle, but there is no way to change a battery? What does a second "master key" cost? Lexus gets $600 for a master key and I dont want to spend that much

 

I believe all Rangers from 1999 on had PATS. My '99 has a very basic system. It just keeps the engine from starting if the correct key is not in the ignition. There is no battery in the keys, Just a transponder that is activated by an antenna around the key cylinder.

 

There is no battery. There's enough power in the RF signal the PATS antenna in the ignition for it to function. Same technology as RFID tags.

 

1999-2011 V6 Rangers all have PATS(passive anti-theft system), in 1998 V6 Rangers PATS was a pay extra Option, so some may have it
2001 to 2011 2.3l 4cyl Rangers all have PATS

One exception, 2005 Rangers 4cyl or V6 do NOT have PATS, Ford had a Licensing issue and could not use PATS for this one year, everything else is the same, just no PATS software

So your 2008 Ranger for sure has PATS

As said above PATS keys require no Batteries, the key handle has an RFID Tag embedded
You can Google: RFID tag

RFID tags are used by many Apartment Buildings and Companies in cards or small FOBs for Access/Entry, i.e. door unlock , or floor access in elevators
No batteries in these cards or Fobs
You put the card or fob next to a RFID Reader and it reads the Number of the RFID Tag, if it a registered number then door unlocks or a floor can be selected on the elevator panel
The RFID reader in this case has power all the time, RFID tag/fob just needs to be put close enough to it to be read

The "reader" is just a powered antenna not the brain, it is connected to a computer in the building that has been programmed with all the issued RFID tag numbers, the computer gets the number then either releases the door's electric lock or doesn't

In a Vehicle the reader is around the key slot, and its activated with Key On and the PATS module gets the number from the RFID Tag in the handle, and that number either Matches one of the 3 or 4 numbers in its memory(programmed in) and you can start the engine, or it doesn't Match and No Start

Any Locksmith can Cut you a new Blank(no number) PATS key to match your locks, and then Read the number in your working key and then CLONE that number to the Blank key handle, this is the least expensive way to get a 2nd PATS key as a spare key