Unless it has changed recently, long-life antifreeze doesnt have to be red/orange and can be yellow/green. Stock coolant in the P5 is long-life and should be completely changed at 4-5 years. To do this correctly is a real hassle because only 50% of it drains out when you open the drain on the bottom of the radiator. There are two ways to do this (with heat on max, fan off)

The long way---drain, refill and recirculate 4-5 times with distilled water.( Dont shortcut the "recirculate" step.) Then fill with 1 gallon of Texaco dexcool.

The quick way--drain radiator, disconnect top radiator hose from the radiator and angle it downward to a bucket (or attach a coupler and an additional hose to extend it past the front of the car to a bucket), add distilled water and run engine till youve run a couple of gallons of water through the system and into the bucket. Then fill with 1 gallon of Texaco dexcool.

Prestone is not to be trusted since they rushed to market with a long-life antifreeze a few years back that didnt protect any radiator with internal soldered connections. I learned this the hard way.

RH

ok ya'll started to bug me out over here. My coolant is on low and I just wanted to know what I should use to full it back to FULL

check again when the car's been driven for a bit.

if it's still on 'low' after the car warms up, add coolant.

DO NOT overfill.