I have a 94 suburban with 84k miles on it I bought it off of my grandfather drove it to florida and when I got there had no oil oil pressure never change temp gauge never went up so I did a full synthetic oil change and drove the truck for 3 months around town mostly and little highway only losing about a quart of oil I moved back to IL this time checking the oil often I would lose about half of 5qts every 400-500 miles I get about 2 hours from my home in IL and see the 1st puff of blue smoke had never smoked befor or after this moment I pull over and check it all the oil is gone empty after like 200 miles so I unload my 14 for focuses and dive my family home grab my dad's truck and head too tow my truck back before I load it I check the oil and it's full I can't find any1 with a similar problem what could cause this
My car has 84000 miles.
My car has an automatic transmission.
Hello. It sounds like your engine may be consuming oil. Blue smoke is usually the result of engine oil being burned in the combustion chamber. It may be possible that the piston rings or valve stem seals have begun to leak, and are allowing oil into the engine. If the issue only occurred after the synthetic oil change then it may be possible that the issue is related to the oil.
In some cases, not all using synthetic oil in an older engine can cause issues due to the tolerances in older engines being less tight than with modern ones. I would also look for any signs of leakage, perhaps one of the gaskets or seals has failed and is causing an issue. If you need help having this checked, a qualified pro from YourMechanic can inspect the loss of oil and pinpoint the root cause.