Can i use a registered trademark if i add another word to it?

[Pgfirebirds]

Specifically, LSX is registered to GM, of course, as a land engine, but if I wanted to open a shop that works specifically on LSX engine performance and cars only, would naming the shop something like " LSX Performance" or "LSX designs", "LSX Racing" etc
would names like above listed be okay as a shop or club name?

[Rob]

No. It just shows your focus is on their engine. If you were creating a business that sold engines and called them LSX engines, then it would infringe.

[bcnu]

As long as you're not advertising that you're an authorized distributor or service shop for those engines, it's okay to "use" the trademark to indicate your shop's specialty.

Similarly, I could have a sign at a used-car lot that says, "Used Chevy and GM Cars", without any trademark license from anyone.

[JSGeare]

That would probably need a court test. It all depends on how GM feels about it.Technically, you'd need to copy the symbology to directly infringe. But you could probably get away with "Performance Solutions - specializing in the LSX power plant."

The best way to know how GM would feel about is to ask them.