Yes I warranty even you do it yourself. It is very unlikely you would mess it up. If you mess up, your transmission will go first. This is possible due to transmission seal damage during the installation. Otherwise, it pretty simple. I also suggest you change out your engine rear main seal at the same time. Good luck and have fun with it. We stand behind our products. If you break it, send it back for another. If it breaks again, you will get full refund PERIOD! No other performance Lexus TC warrenty for LIFE. We are so confident about this product we put this warrenty for our customers. So buy with confident!
I had a guy with my TC. He installed it and forgot to put in tranny oil. Now that is NOT cover. I life warranty the TC if proper steps are taken. If it is your fault... then u pay for your mistakes.