5.3 Yukon ticking in drive and reverse

[Philyukon]

GMC Yukon with roughly 140,000 miles on it and about a year ago it started developing a loud tick/tapping noise from the bottom of the engine. I was told possibly exhaust manifold gasket...replaced those. Still nothing. Weird thing is it only happens in drive or reverse...while moving...or with the foot on the brake either in drive or reverse. I hear nothing when it is in park or neutral. Here is a YouTube video I uploaded.

Any ideas?

 

[DaRosa218]

I could be wrong but from the sound of the video almost sounds more like a Rod Knock or a Wrist pin about to let go.

 

[YukonandtheHOE]

look at your flex plate for warpage or loose bolts, exhaust heat shields will also make weird sounds

 

[Philyukon]

I could be wrong but from the sound of the video almost sounds more like a Rod Knock or a Wrist pin about to let go.

Someone else on a different forum made the same suggestions. My question though is wouldn't it still make the same noise when the engine is revved while in park or neutral? I could be wrong.

 

[Philyukon]

look at your flex plate for warpage or loose bolts, exhaust heat shields will also make weird sounds

Thanks. Will give that a try tomorrow.

 

[DaRosa218]

Someone else on a different forum made the same suggestions. My question though is wouldn't it still make the same noise when the engine is revved while in park or neutral? I could be wrong.

In theory yes and no, it could be where when free reeving its not causing enough stress on the Rods to knock but when under a load it is. My Subaru had ringland failure and would only knock under a load.

Hopefully for you it's nothing like that and just a broken exhaust manifold bolt or something like that.

 

[Philyukon]

Hey guys. I forgot to post here when i solved my problem from the engine tick i had. First I’ll tell you how I resolved the problem then let you guys debate about what might’ve caused it. I’m thinking it was an injector but here goes. It’s been about a year since i resolved it. In July 2018 when gas prices were rising I decide to put $20 of e85 ethanol in the tank to see how it would run since it was only $1.70/gallon. Truck did pretty good. So in a few days i decided to do a full tank of the flex fuel. Magically the sound disappeared within a day of filling up and as of December 2019 it hasn’t come back. I no longer run the ethanol gas in my truck because I have recently had a tune and I run 93 non-ethanol. But even still no more ticking. Thanks again guys.

 

[iAmKendrickRay]

Hey guys. I forgot to post here when i solved my problem from the engine tick i had. First I’ll tell you how I resolved the problem then let you guys debate about what might’ve caused it. I’m thinking it was an injector but here goes. It’s been about a year since i resolved it. In July 2018 when gas prices were rising I decide to put $20 of e85 ethanol in the tank to see how it would run since it was only $1.70/gallon. Truck did pretty good. So in a few days i decided to do a full tank of the flex fuel. Magically the sound disappeared within a day of filling up and as of December 2019 it hasn’t come back. I no longer run the ethanol gas in my truck because I have recently had a tune and I run 93 non-ethanol. But even still no more ticking. Thanks again guys.

WHOA?! WHAT?!?! So you're saying all you did was fill up on e85?!?!

 

[OR VietVet]

The noise was detonation. Cheap gas likely but unsure with no more info.

 

[Philyukon]

WHOA?! WHAT?!?! So you're saying all you did was fill up on e85?!?!

Exactly Kendrick. The ticking started around October 2015 and drove me nuts until i switched to E85 ethanol last summer. Haven’t heard it since. Even took it to 2 different Chevy dealerships and they both wanted to replace cam and lifters which was quoted over $5k. The truck never ran poorly or anything. Just the annoying tick everyday.