What would the cause be for not showing any oil on the dipstick. I have used full synthetic oil and have it changed at about 4,500 miles. There is no evidence of a leak and it doesn’t smoke. They checked for blow back and found none and recommend heavier oil. I have always used 5W20. 5.0 motor, 130k miles. What would you suggest?
I’d suggest checking your oil more frequently. No oil on the dipstick typically represents 2 quarts down or more. Beyond that, start using “high mileage” oil. It’s formulated to help in situations like yours. FWIW, newer vehicles don’t necessarily produce blue smoke because the catalytic converter eliminates it. I learned that here on the forum.
If there are no leaks, the engine is burning oil.
Start checking the oil frequently to determine at what rate.
Then you can decide if this is required.
https://www.restoreusa.com/index.php
Tester
Check the oil level weekly and see how fast it decreases. Add a quart when it is a quart low.
I don’t even wait until it is a quart low . If it is low I just bring it back to the full level . Not that difficult.
If this is a Turbo V6 and it has a good chance of being one… Turbos love to eat oil.
You wont always see the smoke, because when you are looking for it…typically you are not driving behind yourself, or you are standing in the driveway looking when at idle. The times for smoke are when you are driving.
The oil you are using is near thin as water…and you need to be checking that oil one hell of a lot more frequently as others have said.
Appears it’s a V8.
Anyway, I would try 5w30 to slow the consumption down.
There is quite likely some engine damage. The engine does not have to be out of motor oil for this to occur. The only question is how much damage.
So who pointed out the no oil on the stick situation? Running the motor oil low will vastly increase oil consumption.
You say “They checked for blowback…”. Who is “They” and how did they do this?
If this means a compression or leakdown test that may not always be accurate. It’s quite possible for compression rings to be fine but oil control rings may be stuck in the piston grooves. Oil rings are what wipes the cylinders clean of motor oil on each downstroke and if even one oil ring on one piston seized then oil consumption will become a problem.