What is the "offset" for a 2006 Toyota Tacoma

Hello, this is my first post. My Tacoma currently has the original metal stock rims. I'm looking for some nice aluminum wheels that covers pretty much the entire brake (I don't like seeing the brakes between the design on the wheels I've seen out there). When I purchased my truck brand new in 2006, the Toyota Dealer had me come in several times to resolve a vibration issue, which ended up being the Dunlop brand tire. Toyota finally Replaced all 4 tires with Michellin. That seemed to resolve the strong vibration. I've since used Michelin tires. I buy my tires at Costco. They have to use SUV Tires on my Tacoma. Costco also hinted that one of my metal wheels is slightly bent (which I believe is from the dealer trying several times to correct the vibration when I first purchased the truck.) The Costco tire tech advised me to find out what the Toyota "offset" is before I replace my wheels & go to larger tires. I would like to put on the largest size tires/wheels possible without altering the truck at all. I've been advise it's 17" x 7", I have 6 lug pattern 139.7mm. Now this info is a tad foreign to me. I'm ready to finally buy new wheels & it's time for new tires as well. Costco said they would be able to install new wheels on my new tires, but I need the offset info first so I can buy the right wheels & tires. I appreciate ANY & ALL info/feedback. Thanks in advance.

 

Welcome!