On my 06 Escalade I was experiencing slow turn/inconsistant starting. Thought the AAA battery was failing so I called them to come test. It passed, so did the alternator. So I replaced the starter with a duralast gold new. Amazing difference. Clearly the old starter had been going for a long time, i just didn't realize it. Only problems I have had in the past were solenoids, all or nothing starts. In this case it was a tired motor after 10 years. Now it starts so easy and cranks so fast I'm assuming this new starter may help extend the life of the battery.