vehicle 2007 Nissan Titan,Le. I've changed and maintain all the fluids on my titan. I don't tow, I don't beat the truck or 4 wheel the terrain. I have 100,000 miles and the truck runs,,,very good. We also have a 08 jeep, but my truck is more of my concern. You walk down the auto aisle,so much,,junk. No grease fitting to grease, but, does anyone now and then use any gas additive for the injectors? Maybe amsoil PI performance improver? About to buy some tranny fluid and was looking at this additive, reads good, good company,good product? Not looking to fix anything but just help/improve the motor, keep it happy. Or would it be better to get fuel injectors cleaned by a shop? I just don't really trust any,,around me. This product sounds like it does a few more things, not just clean the injectors. Not looking to add every fill up,maybe a 6 month service or so. Any ideals about other products? I've heard horror stories of adding and smoke blowing at start ups and so on. Or, just best to leave alone if no problems?