: 98 Deville, changing the coolant, sealant tabs?

05-13-14, 10:22 AM
Hi all- on my older 4.9 models i have owned i always placed the coolant tabs in the radiator when changing the coolant, my question today is, do i place those coolant tabs into the system on a northstar motor in my 98? And if so do i also need to add some coolant condtioner? Just kind of confused on what to do.

05-13-14, 10:33 AM
DO NOT use those things. They tend to clog heater cores and purge lines. Even GM quit using them back in '03.

05-13-14, 03:58 PM
Yeah that ^^^^

Use a 50/50 mix of whatever coolant floats your boat - just change it every 3 years.

One gallon of raw coolant, one gallon of distilled water (supermarket), and a 2 quart pitcher.

Pour half the distilled water into the pitcher. Fill the distilled water jug with raw coolant. Pour the pitcher of water into the coolant jug. BINGO - 2 gallons of 50/50 coolant and a clean pitcher.

One of the handiest things to have is a big yellow Prestone coolant funnel - the stem snaps into radiator and surge cap necks so it doesn't fall out in the middle of a gallon pour .......................