Newly acquired 04, needs first oil change, but?

[ScottyBoy]

And the shops use crap oil.

EXACTLY. ALL shops use cheap ass oil or at best they use mid-grade oil as their "Top of the line" oil. I've seen oil change places charge $90 for an oil change with Castrol sythetic. ***** ridiculous. I run Amsoil in my truck and in my wife's Altima. It's actually CHEAPER to buy a case of Amsoil (if you have the Preferred Membership which is only $20 a year) than it costs to run conventional oil from an auto parts store. When I order it by the case (12 qts) my price comes to $5.75 a quart. And I was using the Amsoil filters until recently. The Amsoil filters are about $13 each. I have been getting the Mobil1 filters from Rockauto for just under $7 each. So I stock up on those with each Rockauto order. So an oil change costs me less than $50, and I can go at least 7500 miles on that oil. It's a no brainer.

 

[zraffz]

FWIW, I have always been told the reason vehicles leak switching from conventional to synthetic is due to synthetic being a finer oil. It's not eating any gaskets or seal.

Obviously the two can be mixed with no negative effect other than deteriorating the longevity of synthetic oil.

 

[Jamo]

I had a bit of a top end knock one day when I first started my '04 Tahoe last summer. 280+K on her. My wrench nephew had me run 2 qts of ATF (I actually got one qt of Gunk engine flush with one qt ATF) and followed the directions. Let it idle (no rev or drive) for 10-15 minutes, then do your oil & filter change. I have 2500 miles since and will do it again at 3000. All is quiet and running great. Probably just jinxed myself there...

 

[iamdub]

I had a bit of a top end knock one day when I first started my '04 Tahoe last summer. 280+K on her. My wrench nephew had me run 2 qts of ATF (I actually got one qt of Gunk engine flush with one qt ATF) and followed the directions. Let it idle (no rev or drive) for 10-15 minutes, then do your oil & filter change. I have 2500 miles since and will do it again at 3000. All is quiet and running great. Probably just jinxed myself there...

Probably the common stuck lifter tick. ATF is a strong detergent and is commonly used just the way you did by backyard mechanics as an engine flush. Sounds like it did just what you needed. I had an intermittent lifter tick at startup in my '08 when I first got it (at 147K miles) and have been running full synthetic oil since it's first oil change under my ownership. The tick went from happening about 10 times over a 5K-mile OCI to about 5 times to never at all.

 

[Plimbob]

I have used Valvoline High Mileage 5-30 in my 07 Tahoe which now has 244,000 with great results. I also don't skimp on on filters, buy a good grade filter, I like the Purolator 1 or the high end WIX. I think several of the other guys brought up the point that the HM mixtures employ additives to help with the aging of the seals.

If you're bored soemtime and and want to understand more about the different oils and filteration, go to Bob's The Oil Guy website. There are numerous folks on there that truly know what their talking about.