All Edmonton dealers are garbage. They will try to deny it even if the mod has nothing to do with it, when I made the mistake of letting Great West do an alignment (long story), the first word he said was "your kidding me if you want any warranty work on that" just because he seen it was lifted with tires and rims. Unless it's something VERY major, I wouldn't even bother. Less then a week after buying my 04 used, I took it back to the dealer because the stereo was already screwed, our 7 day warranty doesn't cover that, but we will give you a new one for half off, only $550 
It's not exactly the same, but my bro and dad have both tried to get work done on 100% bone stock trucks with no luck, instead they charged $100 because they found nothing wrong.
Just check things over first incase, and then mod it
Need to send the dealerships a message, i'd really like to see what happens even EVERYONE stoped taking their vehicle there for service, even boycott one and see how long before they start honouring warranty.

It's not exactly the same, but my bro and dad have both tried to get work done on 100% bone stock trucks with no luck, instead they charged $100 because they found nothing wrong.
Just check things over first incase, and then mod it

Need to send the dealerships a message, i'd really like to see what happens even EVERYONE stoped taking their vehicle there for service, even boycott one and see how long before they start honouring warranty.