1986 Cadillac Seville was there a recall due to cracking of

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Did you change your coolant with GM coolant system seal tabs(5 bucks at cadillac dealership) every 2 years or 30,000 miles as your owners manual suggests? There is a sticker under hood and in the owner manual that suggests it. These motors, HT 4100 V8's have aluminum blocks with cast iron heads and will have internal coolant leaks if not maintained as cadillac recommends, but most people don't know this and have problems.