Chevy issues - What are your thoughts

[91cavgt]

The alternator went in. It took about 30 minutes. The battery light is off and it doesn't say it isn't charging anymore. So the electrical problem seems to be fixed. I only drove it for about 5 miles yesterday so I don't know if the brakes and the overheating is still a problem.

I agree with a lot of other people when they said it was your serpentine belt/tensioner that was causing a lot of your other issues. Also, what hasn't been brought up on here yet, is that a slow spinning but maxxed out alternator can burn itself up. There is an internal fan in the alternator. If the alternator is spinning enough to put out a charge, but is putting out the maximum charge that it can do at that low rpm, it will build up heat in the alternator. If the rpms are not brought up to allow more air flow, the alternator will cook itself from the inside. After a long time of driving without the alternator putting out enough power, it can also destroy your battery.

As far as why your truck cooled down when you slowed down, does your truck have a mechanical fan? If it does, that is directly attached to your water pump. As air is forced through the radiator from just highway speeds, it will help to turn your water pump even if the serpentine belt is slipping. Cruising at 4,000 rpm with the A/C on is going to build up a LOT of heat, especially when you are driving in 90+ degree weather. You just found the maximum cooling your cooling system is capable of doing.

[stinkbelly]

I am not sure about the mechanical fan.

Before the engine got hot, I had been driving for about 8 hours at the same speed across New Mexico which was about 3-4 degrees hotter. That is why it bothers me. It acts like something went wrong, but then when I slowed down it fixed itself. Maybe it won't fix itself next time or it will do it with less speed/heat/rpm.

[Brooks]

I am not sure about the mechanical fan.

Before the engine got hot, I had been driving for about 8 hours at the same speed across New Mexico which was about 3-4 degrees hotter. That is why it bothers me. It acts like something went wrong, but then when I slowed down it fixed itself. Maybe it won't fix itself next time or it will do it with less speed/heat/rpm.

4000 RPM creates a lot of resistance on the belt. You're trying to drive an alternator, ac compressor, PS pump, water pump/ fan all on the same belt.

[Mike D]

I am not sure about the mechanical fan.



Before the engine got hot, I had been driving for about 8 hours at the same speed across New Mexico which was about 3-4 degrees hotter. That is why it bothers me. It acts like something went wrong, but then when I slowed down it fixed itself. Maybe it won't fix itself next time or it will do it with less speed/heat/rpm.

My truck will run fine for a while when towing but the longer I drive the warmer it gets. Everything gets heat soaked and can't shed heat as efficiently.