Replace it.
This (an old & corroded) ground strap is responsible for more hot start and wiring gremlins that it is given credit for.
When I bought my current project car it had a new starter on it but it would barely crank. It also had a secondary starter solenoid wired in as the typical "hot start" fix.
I replaced the ground with a new one. Pulled out the secondary solenoid and all the crap wiring.
Spun up like a champ whereas it barely cranked. Want to take a guess at how it got the new starter and/or why the car was up for sale?
Do not put dielectric grease on it or between the ground and the attachment points. Unnecessary and will only serve to increase the resistance between the ground strap and it's mating surface.Thanks, should I use star washers or just regular like what was on it?