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Posted

I have an2015 gmc Denali HD with about 65k miles. I just noticed a bad smell while driving(almost like a WD40) When I parked I noticed a clear fluid leaking from what looks like the passenger side of the engine compartment. It is pretty clear fluid. I don’t think it’s coolant or fuel. No Lights or codes and everything seems to be running normal. I have an appointment on Monday but just wondering if anyone may have some thoughts and suggestions of things to look at before then. 

Posted (edited)

brake fluid?  check the reservoir before going, and test the brakes several times that they are solid before driving, and if they seem sketchy or one side of the reservoir has emptied out totally, get it towed in...

 

If it's further back towards the firewall (and at all similar to older trucks), it could also be water dripping from an a/c drain hole (and would be completely normal).

Edited by davester
Posted

Had an engine mount on my 2008 leak, they were filled with a "hydraulic" type fluid that looked like engine oil.

 

It makes quite a mess too, goes everywhere, so maybe some on the exhaust manifold? 

Posted

I will be checking the brake fluid first thing in the morning. They felt fine when I was driving it but I will make sure it’s not them before I drive it again. Thanks for the thought. 
 

It’s leaked a lot of fluid and constantly so I don’t think it’s something smaller like a mount. I haven’t noticed it on the exhaust man at all. It looks like it’s running off the block from underneath. Can’t see the area from the top.   
thank you guys. 

Posted

Have you done the "taste" test on the fluid?

 

Fire the truck up with the AC on full, and wait for a puddle to see if it matches what you have been seeing.

Posted

I have not done a taste test.. I usually don’t lick unknown fluids... lol. But that is a good idea to run the ac. It was cold and snowy today but I’ll let it run with the ac on tomorrow. I’m kind of thinking it may be the def..? Not sure if any of that system runs up towards the motor tho. 

Posted

Depends where your drain tube is "aimed" at, hope that makes sense.

 

Sometimes it is set up aiming straight down, so water will hit the frame rail and go where it wants too, sometimes it will be in a different spot. You can adjust it by hand to go where you want it to drip.

Posted

I don’t think it’s that cause it does have a oily feel to the fluid and a very distinctive smell to it but I will look at that as well. 

  • 4 years later...

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