Engine tick, 05 Tahoe 5.3l

[Tonyrodz]

Did you catch that in time or did something bad happen?

Caught it just in time. Must be a common issue, as it happened to my older Express van too.
Caught this one in time too--just barely tho.

 

[wjburken]

Caught it just in time. Must be a common issue, as it happened to my older Express van too.View attachment 235234
Caught this one in time too--just barely tho.

That’s scary stuff!

 

[Rocket Man]

Caught it just in time. Must be a common issue, as it happened to my older Express van too.View attachment 235234
Caught this one in time too--just barely tho.

Holy crap. Maybe just common to you, Ive never seen it. Maybe you have to drive like a maniac? Which I thought I do, but apparently not...

 

[Jeff O]

Lifter noise in Vortec engines, esp Tahoe/GMC is addressed in a number of youtube vids. Some are fixed with oil additives and various oil manipulations and flushes. Try a search for some possibly inexpensive fixes. However with 270K miles, I expect good old wear and tear is at fault.

 

[sumbum]

So I did some closer listening and paid a bit more attention. So when the engine is cold, like just started, there is no tick or knock. However, once it warms up it's a constant, just much more noticeable over 3k rpm. I've put a video of the sound on YouTube, appreciate any input.

I put tick, but really it's more of a knock...

 

[iamdub]

Really doesn't sound like a lifter tick or exhaust leak in both sound and frequency. Yet, it's still kind high pitched for a bottom end knock. If you had a rocker flopping around enough to slap the valve cover, you'd have a dead cylinder.

I'd check the flexplate and listen to the bottom end with a mechanic's stethoscope if the flexplate checks out.

 

[Rocket Man]

I would put it on jack stands and get underneath to see if it’s coming from the bell housing area. It sounds to me like it corresponds to the speed of the flex plate or crank. I had a similar sound after replacing my trans and it turned out to be the plastic filler piece by the starter, I installed it wrong and it was barely hitting the flex plate. Could be something simple like that.

 

[sumbum]

Really doesn't sound like a lifter tick or exhaust leak in both sound and frequency. Yet, it's still kind high pitched for a bottom end knock. If you had a rocker flopping around enough to slap the valve cover, you'd have a dead cylinder.

I'd check the flexplate and listen to the bottom end with a mechanic's stethoscope if the flexplate checks out.

Is there an easy way to check the flexplate, like using a borescope or something and looking through those inspection areas? I'd hate to pull the transmission if I don't need to yet. I'll pull the valve covers and check for a bad rocker this evening. Really appreciate all the input.

 

[Rocket Man]

Is there an easy way to check the flexplate, like using a borescope or something and looking through those inspection areas? I'd hate to pull the transmission if I don't need to yet. I'll pull the valve covers and check for a bad rocker this evening. Really appreciate all the input.

There’s an inspection plate, it looks like the bottom of a soda can. It’s on the bottom of the bell housing.

 

[sumbum]

I would put it on jack stands and get underneath to see if it’s coming from the bell housing area. It sounds to me like it corresponds to the speed of the flex plate or crank. I had a similar sound after replacing my trans and it turned out to be the plastic filler piece by the starter, I installed it wrong and it was barely hitting the flex plate. Could be something simple like that.

It was doing it before I dropped the oil pan and had both those plastic pieces off. I would assume the plastic would be torn up if it was slapping against the flexplate, however, I didn't notice anything wrong with it. Wish it was something simple though, that's just not my luck lol.