Top of fiberglass radiator slightly leaking, will Prestone Sealant help for Awhile, before I need to replace
My car has 277000 miles.
My car has an automatic transmission.
While sealants like the product you mentioned may be acceptable for emergency repairs, I would not recommend it for this scenario. You need to replace your radiator before it fails during a drive. The leakage you describe is the initial failure of the seal between the plastic end tanks of the radiator and the aluminum radiator core(the finned part that air blows across). This leakage will simply get worse over time. In addition, the plastic end tanks become brittle as they age and go through the cold-hot-cold heat cycles. At some point, perhaps soon with your mileage, the plastic can no longer hold the pressure created in the cooling system. The end tank splits, with massive, sudden coolant loss, and the engine overheats within seconds - often with a failed head gasket or worse. YourMechanic can dispatch a mobile, professional mechanic to your location for this repair. I would recommend having YourMechanic perform a radiator replacement service on your Toyota.
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