Peixinho

Well first off this is not on my corvette... but it is on my 2005 gmc yukon 5.3 motor... i am not a member of any yukon or silverado forums but I figured the motors were very similar and that my friends here might be able to help me out.

Here is the short story... mother n law went 15,000 miles with no oil change (said she was waiting for the oil life to hit zero on the dash). During this event she said the motor was ticking. Every time she brought the car over it would not make any ticking noise. I thought she was imagining things. Well one day she brought it over and it was definitely making a ticking noise. Almost like a noisy lifter or a rod knock (soft rod knock). It was coming from the drivers side and sounds like top end. I freaked out when i heard the noise and thought the motor was blown. Then the noise magically disappeared... nothing... super quiet clean idle.

So i have been driving the car for a couple days trying to figure it out. After a good oil change i put some seafoam in the crankcase which seems to have quietened down the tick. It would not tick while just sitting idling but would start after about 10-15 min on the freeway. After it started it would stay ticking for about 5-10 min... whether parked or still driving on the freeway. The noise is not super loud, if I have the radio on you can barely hear it. Low idle, high idle, revving the motor or even shutting off the motor the noise would not go away for about 5-10 min... After the noise went away for the first time I have never heard it come back, unless i park, let it sit for 30 min and then go driving again, after about 15 min on the freeway the noise would come back and go away after 5-10 min.

So i searched for a long time and decided to run a little atf in the motor for a few days but that did not help, actually it seemed to make the noise happen even more often but still only while driving on the freeway (never at idle). I thought it might be sludged up on the top end so i pulled the valve cover, pulled all the rocker arms out, cleaned the push rods, and sprayed brake cleaner through the push rod into the lifters. While i was in there I found nothing unusual and everything looked very clean. After I cleaned everything and put it back together I let the motor idle for about 30 min, no ticking... yay!!!

So i changed the oil and switched to mobile 1 syn and added 1 quart of lucas treatment. I let the motor idle while I was cleaning up and it sounded good... but then after about 10 min of idling the noise started up... it has never made the noise while just sitting idling. I have always had to drive on the freeway to start the noise. I decided to see what happens if i rev the motor and the noise went away right away. Thought it was a fluke but about 5 min later while idling the motor started ticking again. After a quick rev the noise went away.


I am very confused and I am tired of searching the web (my eyes hurt) so i thought I would ask here.

By the way... motor has 118,000 miles, no leaks, runs great, noise does not affect drive-ability, oil pressure sensor is working and reading correct pressure (just above or below 40 depending on rpm). Noise does not seem to be getting louder and has been around for a few months


Anyone have any ideas???

Alvin@PCMofNC

Based on your description, it sounds like a lifter to me.

Peixinho

i was leaning towards a lifter but i have never heard a lifter noise come and go like this one... do lifters go bad? or do they just get dirty?

From what I have read you have to pull the head to change the lifter. Does anyone know another way to keep from having to pull the head.

NukeC5

If it is a lifter, the head(s) will have to come off. No way around it.

Peixinho

so with all my research i have also decided that it is the sound of a lifter...

But why only one lifter???

Why only after driving on the freeway for a few minutes???

it might have been a fluke yesterday because I took it to am mechanic and cant get it to tick at idle again

sean.b

if it's a lifter, does it damage the cam or anything else? just curious.

Peixinho

I have the same question

Also does anyone know of any tricks to bringing back the life of a lifter...other than what I have already tried

tmarquez

My 05 started making a ticking sound after running it on the freeway for about 30 minutes and has happened twice and both times in the morning. Drove it home today on about an hour drive and the ticking did not come back. I don't get it.

Peixinho

good luck... I never found out the problem... just ended up selling the car...

No i did not pass off the problem. I disclosed the problem showed it to the guy and gave him a good price

04blackice

I've used the c3 or dc detergent additive from auto zone before on a very noisy car. Dirty lifters i guess.anywho put it in 1week before oil change. Took 1 or 2 days and it sounded brand new. Check it out..