2005 Impala 3800 Upper Radiator Hose Flat

I changed out the water pump and failed plastic elbows in the heater core circuit. I had a service station flush out the radiator because I have no way to do this at home. Too cold to get water to car. The service station used Cascade dish washer soap as the flushing agent The dude said it was a GM recommendation so I went with it. Seems all OK.

1. Ever hear of the Cascade flush?

2. Regarding the upper radiator hose. It sucks flat until the engine warms up. This seems abnormal to me. The upper hose is only a year or so old. Is this normal?

Thanks

I changed out the water pump and failed plastic elbows in the heater core circuit. I had a service station flush out the radiator because I have no way to do this at home. Too cold to get water to car. The service station used Cascade dish washer soap as the flushing agent The dude said it was a GM recommendation so I went with it. Seems all OK.

1. Ever hear of the Cascade flush?

2. Regarding the upper radiator hose. It sucks flat until the engine warms up. This seems abnormal to me. The upper hose is only a year or so old. Is this normal?

Thanks

Check your coolant level. And the hoses that run from the expansion tank are not plugged and/or bad cap. And that your coolant bottle itself is not plugged up at the bottom.

I changed out the water pump and failed plastic elbows in the heater core circuit. I had a service station flush out the radiator because I have no way to do this at home. Too cold to get water to car. The service station used Cascade dish washer soap as the flushing agent The dude said it was a GM recommendation so I went with it. Seems all OK.

1. Ever hear of the Cascade flush?

2. Regarding the upper radiator hose. It sucks flat until the engine warms up. This seems abnormal to me. The upper hose is only a year or so old. Is this normal?

Thanks
A lot of radiator hoses have a metal screen inside them to prevent this.