PrestoneAS145 Radiator Sealer Stop Leak - 11 oz.

Was very reluctant to try this but figured a major player in the coolant industry wasn't in the business of ruining engines so we took a chance and put two of these bottles in a fairly large cooling system. Four months later we've not added any coolant and are not experiencing any issues. A $25 investment in this Prestone product has so far saved us $1300 for a radiator, not to mention the truck downtime as we do most of our own repairs.

This worked great and saved me costly repairs.Edit: 5 months & a super hot summer later and it's still repaired. I still highly recommend

When I bought this I gave it about a 5% chance that it actually might work. I was 95% wrong. I had a mystery leak and my system wouldn't pressurize. I added this to my radiator and topped it off with coolant while my engine was cold and drove 2.6 miles to work. Upon arrival I found that my upper radiator hose was hard as a rock and my system was fully pressurized. I wish I could give it 10 stars.

Well worth the money.

Works like it supposed to it sealed up my leak with one application