Need Help with My 2019 Duramax Coolant Reservoir Issues

Questions and Support
1

I’m experiencing some issues with the coolant reservoir on my 2019 Duramax L5P, and I’m looking for some guidance. Lately, I’ve noticed my engine temperature fluctuating more than usual, which has me worried about potential coolant issues.

Here are some symptoms I’ve noticed:

  • Coolant levels seem to drop faster than expected.
  • I sometimes see a coolant leak under the truck after parking.
  • The coolant light occasionally comes on, and I get anxious about overheating.

I’ve done some basic inspections, but I’m not entirely sure what to look for beyond that. I want to ensure that I’m handling this issue properly, whether it’s just a simple top-off or if I need to consider replacing the reservoir itself.

If anyone has experienced similar problems or has tips on maintaining or troubleshooting the coolant reservoir, I’d appreciate any help. Are there particular things I should check or common failure points to be aware of? Thanks for any advice you can give!

2

I’ve heard about coolant reservoir issues in the 2019 Duramax, especially with leaks. Have you checked for any visible cracks or loose connections?

3

I’ve noticed my levels dropping too, but I thought it was just evaporation. Could there be clogs causing this?

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4

Clogs are a possibility, Diana. Sometimes debris can build up and affect the flow. Have you flushed the cooling system recently?

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5

I had a similar issue where my reservoir was overflowing. Turned out my cap wasn’t sealing properly. Definitely check that too!

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6

Great tip! I’ll check the cap. What about the sensors? Any known faults?

7

Yes! The level sensors in the reservoir can be fickle. Sometimes they give false readings. A quick inspection can save you from a headache later!

8

I had irregular levels too! I was so confused until I realized it was just condensation causing the fluctuation. Watch out for temp changes!

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9

That’s interesting! I’m always worried about bigger issues. How do you know if it’s just that?

10

If the levels stabilize after a few days and don’t drop dramatically, it’s likely just condensation. But if you see continuous drops, get it checked!

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11

My 2019 Duramax had a leak so small, it was hard to find. Eventually, a mechanic found it while changing the oil. Might be worth a visit!

12

It’s always a good idea to have a mechanic check for leaks, especially if you’re not sure. Better safe than sorry, right?

13

Definitely! Sometimes it takes a professional to find what’s wrong. I guess that’s why car maintenance can feel like a treasure hunt!

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14

Hey there! For your 2019 Duramax, it’s essential to use the correct coolant. DEX-COOL is what GM recommends. It’s designed for these engines to help prevent issues down the line.

15

I second that! DEX-COOL has some great properties like corrosion resistance. Just remember to check it regularly!

16

Checking coolant every oil change is a solid practice. It might also save you big headaches later. Plus, keep an eye out for any signs of leakage.

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17

That sounds reasonable! Does anyone here use anything other than DEX-COOL? Just wondering if those options are out there.

18

I strictly stick to DEX-COOL for my Duramax. I’ve read mixed things about using other coolants—best to follow the manufacturer’s guidelines if you want to avoid compatibility issues.

19

Remember to flush your coolant system periodically, too! I usually do it every two years, along with a coolant top-up to keep everything running smoothly.

20

That’s helpful! I’ve been meaning to do that for my truck. Thinking about how often folks are replacing coolant—what’s the general thought on that?