Q: Blown head gasket Northstar 4.6L on 1995 Cadillac DeVille

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
Loosing 2 gal. of coolant about every 30 miles.
(2) Answers
the more you drive it, the more damage you do to the motor.
you need a shop to do a leak down test to confirm the number of cylinders effected by the failure. then they can give you a bid based on ther results.
then after this is done, they need to find the original issue as to why it overheated. the head gaskets are a result of the overheating not the reason for overheating.

it will be costly to the point that it may require a new or rebuilt motor.

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