Syn seems to be burning oil, switch to convention?

[TexasTea]

Hey guys, just curious if since im noticing some oil consumption when I switched to synthetic over two years ago (prob 3 or 4 now) that if I do a single conventional oil change if i could watch for any measureable oil burn and compare

Is this a good idea? I know it may not be the end of the world (as some people say) to switch back to conventional for one OCI but im more looking for info about whether the viscocity 5w30 (OEM suggested) in my 2004 Silverado 1500, 5.3L V8, is to blame, or whether its synthetic oil causing the issue. I'd like to really try two changes, both conventional, one 5w30 and one 10w30.

I recall, before finding out that the OEM reccomended 5w30, that my truck usually ran on 10w30 conventional. Then I found out the OEM Suggested 5w30, then I found out about DexOS oils, after switching to synthetic, Quaker State Ultimate Durability 5w30 I am noticing what the OEM states is an "acceptable" level of oil consumption between oil changes, however, the truck NEVER used to burn oil on conventional whether it was 10w30 or 5w30 irrespective.

Just trying to narrow down the issues here. I do realize that we're talking about a mileage span of 60k miles here as well, so it may have nothing to do with oil and simply age/wear of truck/engine, but i do want to cover my bases.

Any input on my over-all ideas here would be welcomed and appreciated,
Thanks,
-Tex

 

[NMBurb02]

Have you checked/cleaned/replaced the PCV valve?

 

[bigt61]

How many total miles on the truck? In Texas, I'd think you'd be fine running a 10w30, especially in a high mileage truck. Try a blend or MaxLIfe and your consumption may drop.

 

[dlundblad]

Originally Posted By: NMBurb02
Have you checked/cleaned/replaced the PCV valve?


This is something to consider. My PCV system as well as my valve cover was going bad.. I too thought it was the oil's fault, but both have since been replaced and I am nearly on a 5k OCI with no sign of consumption.

A high mileage "conventional" (most name brands are synthetic blends these days.) is another good start once you are ready for an oil change.

 

[Bud_One]

Recently changed to synthetic in my 6.0 Chevy. Changed late August of last year. It consumed 2 qts in less than 3k miles - it has since stabilized , and has not consumed since. I'm at roughly 5k currently and is at the top level mark on the dipstick.

 

[Whimsey]

For the first time my 2002 F-150 used some oil in ~3,000+ miles. I switched from using only Motorcraft 5W-20 for 60,000 miles to Havoline 5W-20. It was about a 1/2 quart down from full. Never used any Motorcraft oil in 5,000+++ OCI's. I've noticed in my car when I switch back to Mobil 1 from another synthetic oil it will initially use a little then stabilize and not use any oil for the rest of the OCI.

Whimsey

 

[bubbatime]

11 year old truck in Texas? Run a 10W30 high mileage synthetic blend oil and forget about it. Maxlife, Pennzoil, and Defy would be three good options.

 

[aquariuscsm]

Go back to the same 10W30 conventional you were using and see if the consumption stops.

 

[sicko]

There's no harm in switching back and forth between conventional or synthetic, so go ahead and try it with conventional if you like. If after a couple oil changes you're still burning oil, then you might want to try a quality high mileage oil like Valvoline MaxLife for a few oil changes to see if that slows it down any.

 

[OneEyeJack]

Sometimes the oil is the victim, not the cause.

 

[bmwtechguy]

In Texas summer I would not hesitate to use Mobil 1 High Mileage 10w30 for full syn, or Maxlife 10w30 syn blend. I save the 5w30 for new cars and winter temps. No good reason to run 5w30 in 70-100 deg F in my opinion, esp if an engine consumes oil.

 

[TexasTea]

you guys might be right, these texas heat would probably be more appropriate for a 10w30, but it was my opinion that switching to a synthetic for its heat protective properties would have been a reason to switch to 5w30 year round.

I guess the same could be said for switching to synthetic for its flow and viscosity characteristics such that a 10w30 would be fine for both summer and winter in texas, aye?

i might just go to a Mobil 1 10w30 or Quaker State Ultimate Durability Full Synthetic and see if the burning stops, mind you i did change to both 5w30 and synthetic at the same time, i was running 10w30 conventional. maybe i should've changed over 1 step at a time, but i didnt really think it was THAT big of a difference, especially when i read what i should be running in the owners manual, 5w30 synthetic (or dexos approved oil, which are mostly semi or Full Synthetics)