Hello All,

I have a 2000 Tahoe with a 5.3, and it has just started making a tapping sound after sitting for more than 24 hours, the sound last for about a minute, and then goes away. Sounds like a lifter as I used a stethoscope and found noise coming from right valve cover.
When I took it to local dealer, they said first troubleshooting would be oil change using Mobil 1 and delco filter, and if this did not fix it, then a head job. They then schooled me on using Valvoline and fram filters every 3k miles, and said that this was the cause of all that is evil. I have heard that Mobil 1 is that good, but is it wise to switch after 100k on the motor? Is there really a valve in delco filters that restrict oil from draining down from valves after engine is switched off?

lastly, if it is suspected lifter, is a complete head job required on a motor that has performed flawless up until this?

Thanks in advance to all the experts here that allow DIY's like me to save a few bucks!

 

does sound like a lifter. a head job may not be necessary, but on a motor over 100k miles, probably not a bad idea. as for oil, everyone has there own opinion and preference. personally, i think fram filters are garbage. some swear by them. the dealer will push the mobil 1 because that is what they use. it certainly is a good filter, as is the oil. the delco has an anti drain back valve, which prevents oil from flowing out of the filter the wrong way, not out of the motor. working in the auto parts industry, i do push the mobil 1, but some curse it. oil is same way.

you can replace just the lifters without much worry. switch to synthetic oil is fine too. flush, or have flushed, the motor before adding synthetic, to get all the sludge out.

 

2 oil changes ago i was talked into castrol and i had a lifter knock every time it started too. Just for a min or so. Usually less. I ended up going back to Quaker State. My knock is gone now. That was my fix. It worked for me. Good luck for you.

 

If you do a thread search, MDTAHOE has a flush he recommends for this problem.

This is a minor problem common to the Vortecs, nothing to go ripping your engine apart over.

Strange, but my engine doesn't have this problem, and I went the first 60,000 miles on Valvoline and Fram filters every 3k...

...maybe my truck is "dealerproof?"

That's it, I'm installing an alarm system in this puppy RIGHT NOW.