coolant temp rising and rising.

Have your fluid checked. They may not of cleared out any air pockets and your running very low on fluid. Did they change your water pump also? If so make sure it is the correct one. If you have a friend with the same model car, compare their belt routing with the one you have on the car. If it is under warranty, go back to them or another car dealer you trust. If you got a 2008 car, is it under the 30 day warranty or just the repairs covered. Take it back and have them fix it.

I checked and topped off the antifreeze and oil and it seemed to help a little but its still running too hot. they did not change the water pump as far as I know. but they wanted $500 to replace the belt before we told them where they could stash that. it was still a $300 job. I bought the extended warranty and its still good. belts are not covered. ha ha go figure. it seems that they will fix something that is wrong with the car but they always pretend that its something that is not under warranty. for example, they might lie and replace the alternator, but charge me $500 for a belt. this is the GM dealership. >:( I get no honesty or explanations from them so its really hard for me to diagnose anything.

I have gone to the dealership for factory warranty work, but most all other if I can't do it myself or don't have the time, I found an independent repair facility that I have used for over 25 years. He covers all warranty work, does it right, will at times fix at no charge little things, and is great at explanations on what is wrong. 1/2 or less the dealership costs also. He will show his invoice for the parts replaced and I get it as his cost. Yes dealerships charge $300+ for a belt change out, but it takes less than an hour depending on what must be removed and replaced. When driving and it starts to hear above normal operating temp, pull over to a safe place and raise the hood. Can you hear or see if the fans are working? If not, there is your problem. Unplugged or lose/broken wire done by them doing the work. If the fans are running, check the hoses visibly and make sure they are not collapsing under pressure. They should then be replaced. (Not covered by warranty BTW) See if the thermostat is covered by warranty. If so have them change it out. The fans should be covered also. What I would do is ask around with friends for that little independent repair shop and see if they honor the warranty. It wouldn't hurt to talk to that shop about repairs, warranty work, and cost. Dealerships make money by charging by the hour no matter if the job takes 15 minutes or an hour. The labor cost is the same. If they go over the estimate, they bump it up again. Ask the little garage if they do the same or charge for time spent. Why was the belt changed? If you just bought the car from the dealer, it should have been checked and in good operation when you drove it off the lot. Are you sure it needed replacement? Normally they are good for at least 60,000 miles.