KROIL Original Penetrating Oil, King Size, 13 oz. aerosol (KanoLab Aerokroil)

I have used this many times, and I have never been let down by its performance. I have used other sprays on rusted and stuck bolts and nuts that did nothing to help, but I would use this and let it soak for a little while, and they would almost always come loose.

I recently tackled replacing both exhaust manifolds on my 2012 F250 with a 6.2 gas engine – a job known known to turn into a nightmare as these manifolds are infamous for snapping bolts, and I was dreading it. In my decades of shade tree wrenching, I'd never used Kroil before, but after reading countless forum threads praising it, I figured it was worth a shot to avoid the extra hours (and headaches) that come with removing broken bolts. The results? Absolutely validating. I used the entire can for the job, making sure to thoroughly soak those bolts. Every single one came out without breaking. I couldn't believe it – a job I was sure would turn into a multi-day ordeal with broken bolts and extractors went smoothly because I took the time to let Kroil do its work. I'm now a true believer and advocate of Kroil. I'll never not have Kroil in my garage. In fact, I was so impressed that I bought the 17-ounce can to keep on hand for future jobs. The investment in a can of Kroil is nothing compared to the time and aggravation it can save you on a job like this. For anyone facing the rusted, ages, or seized fasteners, especially on exhaust manifold bolts, I'd say Kroil is absolutely worth having in your arsenal. It turned what could have been a nightmare into a straightforward repair.