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Does it get warm when you drive?
yes, or when i rev it up it will blow hot, then cool back down at idle
How many miles on the truck?
Somethings you may want to check
First off when you get warm air when driving, and cold or cool when stopped, that is normally due to a air pocket in the coolant system
Now, this is what you need to listen to for you to check,
The 2005 through 2010 Nissan Pathfinder, Xttera and Frontier got a warranty extension on there Radiators. This extension is for 8 years or 80k miles. The reason for this extension is cause the trans cooler inside the radiators have been failing prematurely. When this happens coolant can enter the trans, and trans fluid can enter the coolant system. But when coolant enters the trans, it contaminates it. Once this problem start, you may feel a vibration at highway speeds. This vibration may resemble the rumble strips on the side of the highway. If you have this type of vibration, then your trans has been contaminated by the coolant. If your with in the 8 years or 80k miles Nissan will cover the transmission if it was damaged by the radiator, because the radiator is the cause of the condition or failure. So the radiator and trans would be replaced under warranty
Since you have over 80k miles, I would look into installing a external Trans cooler, and do a trans service using Nissan Matic S
what about the heating problem
All you need to do is bleed the coolant system
Then after you pinch off these lines
This is how you bleed the coolant system
To bleed the coolant system, remove the radiator cap. Install the coolant bucket. Fill the bucket about 1/2 way. Then raise the front of the car as high as if it were on ramps. This way if there is air in the coolant system, the circulation brings it to the highest point. Then turn on the car, and put the heat on speed number 4, recirc mode on, and face mode. You may need to rev the engine to move the coolant around to get the air out. After you have good heat, and little to no bubbles in the coolant bucket. Then the coolant system is properly bleed. You should have good heat when bleed properly. So when you put your hand over the vent and hold it there for 30 seconds, you get a slight burning sensation. That is perfect heat.
If you can't manage to get a coolant bucket, you can try to make one. Here is a image as a example.
If you have any more questions on this, please feel free to ask. Thanks Jay!
when you say pinch the lines, take them off and fold them over? and the homemade bucket just fits over the hole where the radiator cap goes?
No don't remove them, just pinch them
with vice grips or something?
yes, just put hoses over the tips of the vise grips so it doesn't damage the lines
ok, thanks, what about the homemade bucket?
You remove the radiator cap and make it snug to fit.
ok. thanks for the help
Then fill it about 1/2 way and run the truck to bleed it outl
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Don't forget to press the ACCEPT button if you satisfied with my help. Thanks Jay!