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Old 06-28-2025, 08:28 AM   #1
57FleetsideC4
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Coolant Dribbles out

Hi, I have a 57 pickup with a LQ4/4L80E powertrain and notice when driving it a while it with dribble some coolant out the overflow. It is not overheating runs around 180-190 going down the road. I did add some coolant in the spring and maybe it is overfull. Just wondering if anyone else has seen this, Thanks Steve
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Old 06-28-2025, 09:42 AM   #2
AussieinNC
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Re: Coolant Dribbles out

Hi Steve.

Does your cooling system have a coolant recovery tank like a OE system or is the overflow tube just exiting from top of radiator under the radiator cap?

Edit "Just checked your build thread...beautiful truck sir. I can see you dont have an OE recovery style system, at least in the pics on the post. "

I would double check the cap pressure is good, and or put another slightly higher pressure cap on it and check.

Let us know.

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Last edited by AussieinNC; 06-28-2025 at 09:51 AM.
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Old 06-28-2025, 10:37 AM   #3
Joyridin
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Re: Coolant Dribbles out

I have an overflow bottle on my LT engine and LS engine. Both move up and down quite a bit from hot to cold. With no overflow, you might have just filled it too full when it got hot and expanded.
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Old 06-30-2025, 09:21 AM   #4
57FleetsideC4
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Re: Coolant Dribbles out

Thanks guys, I tested the cap with my pressure checker and go to 15.5 lbs then will dop and hold at 13.5 lbs. I tested another same cap and it goes to the same 15.5 but only drops to 15 and holds. These are 16lb caps so think I have a bad cap. Will know for sure the next time I drive with the good cap. Steve
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Old 07-28-2025, 08:54 AM   #5
57FleetsideC4
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Re: Coolant Dribbles out

I have had the truck out a couple of times with the replacement cap and no more dribbling. So the cap was the problem. Steve
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