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Discussion Starter #1
I am new to this forum. Actually it's the first forum I've ever joined so thank you for having me.

I AM NOT A MECHANIC BUT I DO FOLLOW DIRECTIONS WELL. LATELY ALL MY DIRECTION HAS COME FROM YOUTUBE. I have a 2007 SR5 5.7L. I have several issues but the immediate issue that I need to be resolved is it running hot. A few weeks ago the radiator burst on me. The plastic around the top of the radiator shattered. So I replaced the radiator and within 2 miles the truck started running hot. I thought thermostat so I changed it and it didn't fix the problem. Next I changed the water pump and that didn't work either. Everything seems to be working fine while it's idling but after about 15 minutes of idling and the occasional reving up the motor to around 2500RPM, the temp starts rising. Is there a blockage in the coolant lines? Maybe air in the lines? Or something worse. Please help. The other issues are the transmission solenoids. It will not shift out of 4th gear. I have to manually shift gears and I only have gears 1-4. Also it will not go into 4WD. I believe it is the actuator motor but not sure. Thanks!
 

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Fan clutch could be failing.
 

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The fan seems to be working fine. When I remove the radiator cap the coolant bubbles. Does this indicate air in the coolant lines? When I crank it struggled to turn over like it's gurgling.
 

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When a fan clutch fails, it still spins, just it doesn't lock up properly to spin faster when needed.

However, that doesn't seem like your issue with the info you just added.

Bubbling coolant is typically an indicator of a blown head gasket. The struggling to crank, and gurgling could be the cylinders filling with coolant after you shut it off.
 

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That doesn't sound good. Are there any test I can run myself to check before I go changing a head gasket? What are some other indications? There are signs that would lead me to believe that fan clutch is indeed an issue. For instance, when idling for about 15 minutes it will start to run hot but if I give it gas raising the RPMs it starts cooling down. I also think you may be right about the blown head gasket. It seems like there is a compression issue for sure. I read somewhere on here that there could be air in the lines that needs to be removed. I changed the radiator myself and drained the fluid twice again when I changed the thermostat then the water pump. Neither of those appeared to be broken. Is there something I could have done incorrectly? This all started when my radiator burst on me doing 85mph passing a car in 4th gear during an emergency.
 

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The fan clutch is supposed to slip under normal conditions, till it gets hot, then it is supposed to lockup. It should be locked up when you start the vehicle, which will make a louder than normal fan noise, then after 5 seconds or so it will go into slip mode.

I am not sure if the engine has a bleeder for coolant. Some vehicles do as air can get trapped in the upper passages, and just be stuck their air locked basically. I have not seen bleeding issues on the cooling system, so I don't think that is the issue, but not 100%.

A blown head gasket can be detected in several ways. One is a combustion gas detection test, where you test the cooling system for combustion gasses. You can also do a leakdown test on each cylinder. You can also pressurize the cooling system, which normally just tells if you have a leak somewhere, but if a head gasket is blown between the coolant area, and the cylinder, it will normally fill a cylinder with coolant. This is the basic explanation,

I just dealt with this on a co-workers vehicle. Slightly blown head gasket, not enough combustion gasses to be easily detected with a combustion gas test, however with the coolant pressurizing gauge on it, you could start the vehicle, and it would peg the gauge after a short period of time. It was not worth putting $1800 into for the head gaskets, so she is now just driving it and adding coolant in the morning. Her issue is not as severe as yours.
 
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