Depends. Who sent you an offer and what does it say? Generally, a set APR is a good sign, as is a specific link to go to to activate the offer - but it depends on the credit issuer. Please give details so we can help, thanks!
Speedway (the gas stations, right? We don't have any where I'm at but I've heard of them), are usually good to rebuilders so the pre-approval should be ok and your scores are fair. TD, I'd look for a single APR in the flier. I just got a Target card myself so I'm not as familiar with their pre-qualifications. Capital one auto you're probably good for but that's kinda worthless to you unless you're looking for another vehicle. You won't be able to refinance your loan with them. Again, everything is still YMMV though.