I have a friend that is about to open a food truck and he has asked me to use my burger recipe. I have spent a long time perfecting it, but I have always made it with thick patties meant for the grill and not for the griddle, which is all he will have inside the truck. Since the best griddled burgers are the smashed patty type, I want to adapt my recipe to work well with this new cooking method. Am I going to need to play with my seasoning/spicing ratio?
Does your burger recipe rely on the center of the burger being medium rare? If so, you may have a problem with the spice ratio because your cooking technique will produce different types of doneness on the grill vs. the griddle.
With the grill you get a higher quantity of crispy burny bits (the Maillard reaction) than you will on a griddle (temperature generally in the high 300s F, as opposed to much higher grill heat). With the grill at home you can go for a rare to medium rare center. with a lunch truck, you had best go for medium well for safety's sake (and possible legalities).
The easiest way to know how your recipe will work under griddle conditions is to test it. Make up your burger, pat it thin and cook it all the way through in a medium heat fry pan (not my favorite way to have a burger, but classic griddle approach). If all is well, you're done. If not, well, you've already perfected it once, you'll need to decide what changes need to be made.
But I'm betting that perfection will carry through to the griddle burger just fine.