My chevy drives for 45mins then shuts off

most commonly found problem relates to an electronic component heating up and shutting down. Have you checked to confirm there is fuel pressure when the vehicle shuts off. Is the check engine light on. Have you checked codes ? I suggest hooking up a fuel pressure gauge and letting vehicle run till it shuts off while monitoring the fuel pressure. If you loose fuel pressure, next step is to confirm there power going to the pump, if there is power going to the pump with no fuel pressure replace pump. Another suggestion would be to check for spark when vehicle stops running to eliminate an ignition problem. good luck

WHAT KIND OF CAR

check the check engine light my dodge was doing that 2 sum bout the cooling system dont knw 2 much bout cars but it dont do it knw just when i drive it bout 45 mins and cut it off it wont started back up for about 45 min

Check the car service is there any problem occurred for the engine and try to change it....

check the connection on your battery terminal ends. if they are loose or corroded that could explain the intermittent no spark. also could be a short somewhere but id check the terminals first. I had that problem once and the car did all sorts of weird things. airbag light, check engine light, randomly wouldnt start until i would mess with the battery.

sounds to me like you have a short in the ignition itself , it seems intermittent which would make me believe its the ignition

remove expansion tank cap (if fitted) take off the highest hose clip in the system and fill from there if you have an air lock in the system it will be obvious...after connecting back up, fill tank with neat anti freeze.(if tank is higher than hose, fill tank as air is expelled from the pipe.)

There's a possibility that your fuel pump is going out. What's happening is that you can drive for the 45 min. and the pump gets hot and shuts itself off. After it cools off, it starts working again.

You probably have some corrosion on your battery terminals. Make sure they are clean and connected good and tight.

burn out transmission.