need help. on road trip overheating

[alc5m]

Hey guys I've got an issue here. My 03 5.3 keeps killing itself while driving. The first few times this trip engine bay had been normal operating temp. By feel. This last time I had the air on had yo wait half hour to cool down

This has happened twice beforein the last month. Idled for almost 45 minutes in a parking garage leaving an event hit the gas to go and killed it. Alternator was burning to the touch

Replaced alt and about two weeks later (earlier this week) I pulled a trailer ubhooked it went to a drive thru and when I left there it killed itself.

First two times were after idle these times on the trip are freeway

Nothing wrong on the gauges. No dummy lights no check engine. Temp gauge stays at 190/210 area.

Anyone have any ideas. My first thought is water pump or thermostat but I can't be sure. Can't check the weep hole. Lowered a bit plus z71 skid plate means no go on that.

Any help is appreciated thanks guys

 

[yates ™]

What exactly is over heating? You mentioned the alternator was hot and you replaced it and now worried about water pump and thermostat but the temp is not showing hot. I think it sounds like you have an electrical problem and that you are not over heating but then again I am having trouble following what is being said.

 

[alc5m]

Sorry. Frustrated typing lol

I had the thought if an electrical problem the first time it happened which is why I had replaced the alt the first time it happened.

The engine bay, when the truck dies and doesn't start up again right away, is extremely hot. The alt is prob super hot to the touch just because of heat transfer to the aluminum housing.g as well as the brushes and coils. The other thought I had was the alt gets too hot for the charging to function properly but then the question becomes why is it overheating like that?

Only other thing electrical I replaced recently was upgrading my battery to a yellow top but I had that In for 4 months before first time it overheated

 

[yates ™]

Lets rule out fluid, what does your temp gauge read, is there anywhere that you can see that antifreeze has sprayed out?

Are you sure you are not grounding out anywhere in the wiring?

 

[alc5m]

Gauges read normal across the board and I don't see coolant anywhere in the bay besides in the resivoire.

Not sure about grounding out cause I never really changed anything to where something could ground out. Any ideas on what wires to look for. Also any ideas as to why the engine bay got way hotter with the AC running than without?

 

[Rivieraracing]

Try cleaning your throttle body, sounds kinda like the problem I get when mine gets very dirty!

 

[alc5m]

What would a bad thermostat give for issues?

 

[zieglerj-pdm-specialist]

But IF??

If the temperature is not showing that its overheating you can rule that out unless the temp gauge is defective. Does the engine warm up from zero to the point where the temp gauge climbs to the natural running temp, the gauge is not stuck on 210 or whatever it may be. I don't see how the alternator would get so hot that you cant touch it?? unless some wires are loose generating more heat than it should. You need a good solid connection on the alternator or it will generate extra heat. Is for some reason your brake or emergency break me be faulty and causing the engine to over work. How is your gas mileage and your RPM while running at normal speed of 65? If it was your water pump it would be leaking throwing your serpentine belt if its locked up or it would make gravely noise from bad bearings. Pull the air filter out and see if your engine runs better just by sitting idle. The vehicle maybe trying hard to suck the air in and its starving for air causing overheat. That's my 2 cents does any one agree? Or am I way off base again.

---------- Post added at 06:46 PM ---------- Previous post was at 06:44 PM ----------

What would a bad thermostat give for issues?

A Bad thermostat would not give your vehicle any coolant there for causing your engine to over heat in a couple miles of driving it. Your temperature gauge on your dash will be hotter than 225 it would get near the red.

 

[alc5m]

What about it vapor locking the engine though?

There was an Allstate service guy who stopped and that was one of his thoughts.

And as far as I know I tightened everything in the alternator as tight as it could go

 

[zieglerj-pdm-specialist]

What year is you vehicle

Gauges read normal across the board and I don't see coolant anywhere in the bay besides in the resivoire.

Not sure about grounding out cause I never really changed anything to where something could ground out. Any ideas on what wires to look for. Also any ideas as to why the engine bay got way hotter with the AC running than without?

By using the A/c it engages the A/C compressor causing the engine to work a little harder but nothing that was cause heat like your explaining unless the bearings on the clutch or the bearings on the compressor are going bad in which you would hear a grumbling noise from a bad roller element. Start it up open the hood and listen for anything that is making more noise than any other piece under the hood. I just wish I had all the details of this problem and we could figure this out if we knew everything that happens, when it happens, how it happens, are you towing anything. check the brakes. Im here to help but I need all the details.