What Size is the Thread for LS1 Coolant Temp Sensor?

Maintenance and Repairs
1

I’m currently working on my LS1 setup and I need to replace the coolant temp sensor. I’ve done a bit of research, but I keep coming across different thread sizes and I just want to confirm what the correct size is before I order a new one.

Here’s what I’m looking for:

  • Thread size (diameter and pitch)
  • Any specific brand recommendations for sensors.
  • Additionally, if anyone has tips on switching out the sensor without causing any leaks, that would be super helpful!

General Context:

I’ve got my LS1 in a 2001 Camaro, and I’m upgrading some of the cooling components. The stock sensor has been acting up, and I want to make sure I get the correct replacement.

Bonus Questions:

  • Are there any performance gains from switching to an aftermarket sensor?
  • Have you all had any issues with fitment while installing new sensors? Any advice on this would be greatly appreciated!

Let’s keep this discussion fruitful and help each other out. Thanks in advance!

2

The thread size for the LS1 coolant temp sensor is typically 1/8 NPT. This is pretty standard across many models. Double-check your manual to confirm!

3

Thanks for that info! Is this size consistent in all LS1 models, or is there variation between years?

7 Likes
4

In general, LS1s maintain that 1/8 NPT thread, but some specific applications might differ slightly. Always best to verify with the specific model year.

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5

Good to know! How do I confirm the thread size if I already have the sensor?

6

You can use a thread pitch gauge or simply try threading it into the housing lightly. If it fits snug without cross-threading, you have the right size.

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7

That makes sense! I had a friend tell me to use tape, but I wasn’t sure about that.

8

Using tape can be useful for sealing but make sure it doesn’t interfere with the threading. Sometimes it just complicates things!

9

Yeah, it’s a fine line. A little tape can help, but too much and you might just cause a leak later on!

10

Exactly! It’s a delicate balance. Can anyone share their experiences with sensor replacements?

11

I’ve replaced my LS1 sensor a couple of times due to leaks. Definitely learned to double-check thread sizes before tightening!

12

Wow! That’s a good tip—better safe than sorry. I guess thread sizes really do matter!

13

The thread size for the LS1 coolant temp sensor is typically 1/4-18 NPT. When installing, make sure to use some thread sealant to ensure a tight seal and prevent leaks.

14

Great info! Can anyone share tips on how to apply sealant effectively without overdoing it?

15

When applying thread sealant, just a thin coat is enough. Over-applying can actually clog the sensor! Spot on advice, xfoster.

16

Good to know! Is there a specific type of sealant that works best for coolant applications?

17

I usually go for PTFE tape or liquid thread sealant specifically rated for coolant. Just make sure it’s compatible and won’t break down in the long run.

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18

Remember not to overtighten the sensor; that can damage the threads. Hand-tight plus a quarter turn is usually best for a good seal.

19

That’s super helpful! Any thoughts on what to do if you suspect the threads are damaged?

20

If you think the threads are damaged, you could try a thread repair kit. Sometimes, a tap can clean them up enough to work again, if they’re not too far gone.