Oil Consumption

[Wylie_Tahoe]

03 5.3L Flex.

Only have 5 week on it since reman trans, fixed some oil leaks and fresh oil change. Checked today, which is likely 4 weeks since last check, and was down .5 qrt. Likely have less then 1,000 miles on this oil, so .5 qrt is a lot.

I do not know what oil has been run before, but went with the recommended weight of 5W-30. Valvoline High Mileage to be specific.

Going to log the mileage and note the level, and monitor til next oil change. May change weight and/or back to non high mileage for next service.

Anyone else notice an increase in consumption using the 5W-30 and changed and it was reduced?

 

[Wylie_Tahoe]

UPDATE;

After 205 miles, im down 1/4 qrt.

 

[SnowDrifter]

Now many miles are on your rig?

Any notable leaks?

Notice blue smoke on startup?

Checked pcv system?

Any oil in coolant? Didn't see it specified if you have an oil cooler.

How'd compression and leak down tests look?

Take a scope to your pistons? Any of them show higher than normal carbon buildup?

Note same behavior across different oils? I. E. Rule out some volatility loss?

 

[Wylie_Tahoe]

Now many miles are on your rig

299674. I only know the history from the 293000 make

Any notable leaks?

Addressed those when the transmission was changed at 298,***. Any loss of oil now, is not hitting the pavement.

Notice blue smoke on startup?

No blue upon start up or running

Checked pcv system?

PVC and throttle body serviced and cleaned when I converted the wet intake back to the stock dry filter and intake ducting. 297,ish
Noo o

Any oil in coolant? Didn't see it specified if you have an oil cooler.

No oil in coolant, yes on an oil cooler (tow package)

How'd compression and leak down tests look?

Waiting on this to do along with plugs and wires. Likely next week

Note same behavior across different oils?

Thats the opening question in this thread for others. As noted, I only know the history since May and the 293000 mark. I do not know what oil was in it, but I was topping off with 10W-**. First oil change was when the trasn was installed and I used the recommended 5W-30.

Was curios if others found some consumption while using the 5W-30 and noticed a reduction/increase after switching to a different weight.

Next oil change will likely be due about the time the weather changes, so I will likely change weights and continue to monitor consumption through the next cycle.

 

[SnowDrifter]

Kind of hard to not call worn engine with that many miles, but with an unknown history, you might try a solvent soak in the pistons. Take the plus out, pour solvent in, let soak, turn over, put plugs back in, change oil. There's a chance it could be a case of oil control rings plugged up with carbon and they're not moving freely

 

[Wylie_Tahoe]

Kind of hard to not call worn engine with that many miles,

i agree. But with the amount of oil leak I had prior to fixing them, I am quite surprised at the amount of oil im needing to top off. the only other thing that changed, or might have changed, was pouring in the recommended 5W-30.

Its also the first ive ever used the Valvoline High Mileage.

The GM Top Engine cleaner is (was) the absolute chit! Cant count the number of cans I used on the 4.3L after replacing failed "spider" injectors and cleaning out the EGR valves. May get a couple cans and run some through prior to the new plugs.

 

[SnowDrifter]

i agree. But with the amount of oil leak I had prior to fixing them, I am quite surprised at the amount of oil im needing to top off. the only other thing that changed, or might have changed, was pouring in the recommended 5W-30.

Its also the first ive ever used the Valvoline High Mileage.

The GM Top Engine cleaner is (was) the absolute chit! Cant count the number of cans I used on the 4.3L after replacing failed "spider" injectors and cleaning out the EGR valves. May get a couple cans and run some through prior to the new plugs.

Haven't used that particular oil, but I've not noticed any oil burning with M1 esp 0w30 or Castrol euro spec 0w40. I run those 2 in my rig pretty well exclusively. Have pretty good HTHS numbers, good (low) volatility. Might try giving either of them a run? I also have half the mileage you do

 

[afpj]

Several anecdotes of rotella gas truck 5w-30 reducing oil consumption of other users... something about higher viscosity. Not really a believer of the high mileage oil claims, but some people like it. Then there's the " potential" difference between the synth blend vs fulll synthetic for Valvoline high mileage oil.
Anecdotally, I used Valvoline HM synthetic blend for years, and had steady oil leak. Switched to VHM full synthetic, and leak appeared worse. Switched to rotella, leak better. Lots of other potential variables, but I like the rotella.

 

[avalonandl]

With that high a miles using a quart every 2000 miles....not out of range as normal.

 

[Wylie_Tahoe]

The comments about syn and syn blend made me go check on something. The valvoline im using is labeled by NAPA, but clearly states on the back, its by valvoline. No where on the bottle or online, do I see that its syn or a syn blend. Conventional was what I was after. Looking on valvoline's site, they do not show a conventional high mileage though.

Ill continue to monitor, but likely going to move to standard conventional next oil change.

Thanks for the info @afpj

 

[mijohnst]

I have a Yukon XL and it burns about 1 quart about every 5k miles. I think it's a common thing with high miles on a 5.3. I just check it every oil change and then don't think too much about it.

 

[HiHoeSilver]

I have a Yukon XL and it burns about 1 quart about every 5k miles. I think it's a common thing with high miles on a 5.3. I just check it every oil change and then don't think too much about it.

Are you running a catch can?

 

[Wylie_Tahoe]

Been awhile! In a normal year, I expected to hit my target change mileage mid spring. However, due to covid, I was idle, pardon the pun, until the end of May. Since then, ive been running 7 days a week and hit my change interval the end of Aug, but still too busy to change the oil till now.

So here is what I found. My oil consumption has actually dropped. I not only check the oil frequently, but I note trips that had me at hiway speeds for extended periods, as these increase the consumption compared to just average, stop and go mileage.

Was it the hi-mileage NAPA oil? Was it all the other tune-up and preventative maintenance services ive done? Dont know.

So I changed the oil/filter this AM, going back with the same NAPA (Valvoline) conventional high mileage oil as I did last fall. Ill keep logging the consumption based on mileage and how much I have to add between changes.

Ive also seen a slight up-tick in the average MPG mileage. I know the services ive done helped here, but the high mileage oil blend could have helped a little as well. Hard to say since a ton of work went into this rig in the 2nd 6 months of owning.

 

[Mudsport96]

I dont know if the 03 has the integrated valve cover/pcv or if that came later. The 06 silvy I have now was originally my father in laws truck. It had oil consumption of about 1qt every 1000 miles with the odometer around 240k miles. I went to the junkyard and grabbed a valve cover off of an 00 and put it on the truck for him. Oil consumption went way down to about .5 every 2000 miles.
It is now my daughter's truck with 400k on the engine and it eats 3/4s of a quart every 1000 miles. But to keep pressure where I like it to be I run 10w40.

 

[mdmcinti]

My 03 Yukon loses about 2 quarts of oil in 4K-5k miles due to a leaking rear main seal. It doesn’t eat oil because I changed the original pcv valve and it was surprisingly pretty clean and not clogged with oil. My rig has 242k miles and I do lots of highway trips since my commute and where I live I need to drive to get to some places. I have owned my rig since February of 2020 and put 21k miles on it in 8 months.