I've been using regular old Prestone ethylene glycol based coolant and haven't had any problems. My indie Volvo specialist buddy says there shouldn't be any problems with using that, if the system is flushed every two years or so. He only uses the special coolants in the very new cars that specifically require it. My '02 Jeep requires the special orange crap that all new Diamler/Chrysler cars use, and there does seem to be some different chemistry there. But I can still buy it from the local parts shop for a lot less than the dealership.

I absolutely do not believe these manufacturer claims of lifetime coolants and fluids in cars going back to the 90's (I'm leary of it in new cars to), especially when they are using the same stuff you can buy off the shelf for older cars and those cars recommend changes. I seriously doubt the OEM coolant Volvo was providing in 1997 is any different than the off the shelf coolants, so how can they claim it never has to be changed? If I remember correctly, they also said the transmission fluid never had to be changed as well.....hmmmmm. Very stange when they were using regular old Dex III, which in practically every other car using that type of fluid the manufacturer recommends periodic changes.

For what a gallon of antifreeze costs and the little effort involved in draining and flushing the system, it's well worth my 10 bucks and half hour of time to get that added insurance and peace of mind.