I am asking for a co-worker of mine with an Impala 3.4V6, he says he adds about a quart of oil every 2,000 miles and generally goes 5,000 between oil changes, so that's over 2qts of make up oil in a 5,000 OCI, my theory is for every qt. of oil you add before your next OCI , you can extend it another 1,000 miles, this is assuming a 4 qt sump. I didn't tell him that, but that's my new theory, any logic to this theory?
Make up oil means can extend OCI?
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You are renewing the additives, averaging out the sheared viscosity level with the fresh oil's viscosity level... and concentrating whatever wear particles, fuel, blow-by ash, coolant, induction grit, condensation, and/or other contaminants.
I've read the many threads here on this topic, and my only conclusion is that you can get away with a LOT and still keep an engine running AS LONG AS you keep the oil level at a safe minimum.
But getting away with minimal maintenance versus optimal care are two very different things, especially as an engine ages.
I've read the many threads here on this topic, and my only conclusion is that you can get away with a LOT and still keep an engine running AS LONG AS you keep the oil level at a safe minimum.
But getting away with minimal maintenance versus optimal care are two very different things, especially as an engine ages.
What are his driving conditions? I ran my 3.1 about 6k miles on Pennzoil Platinum with some of heavy idle time and the TBN was in the upper 1.8 range so not much wiggle room for severe service. My engine doesn't consume oil though, that does boost the TBN.
These 3.1/3.4 engines are usually happy with 5k dino changes, but adding the extra oil should get him more mileage.
Your 1k mile extra for every quart is a solid hypothesis, just get a baseline uoa at 5k and another one after 8k to verify.
These 3.1/3.4 engines are usually happy with 5k dino changes, but adding the extra oil should get him more mileage.
Your 1k mile extra for every quart is a solid hypothesis, just get a baseline uoa at 5k and another one after 8k to verify.
I would add 1 quart every 2k miles at 2k, 4k, 6k and 8k then change at 10k.
Originally Posted By: HTSS_TR
I would add 1 quart every 2k miles at 2k, 4k, 6k and 8k then change at 10k.
I agree. Make up oil has a pretty significant effect on the TBN of the oil. Its not linear with the amount you are adding.
I would add 1 quart every 2k miles at 2k, 4k, 6k and 8k then change at 10k.
I agree. Make up oil has a pretty significant effect on the TBN of the oil. Its not linear with the amount you are adding.
Make-up oil like;
Put another 5 gallon pail in the bath tub water.
or
You might like all fresh water, or a shower better.
Put another 5 gallon pail in the bath tub water.
or
You might like all fresh water, or a shower better.
If the oil is going somewhere it might be working harder than expected. This could be from hard driving, difficult conditions, a PCV problem or an engine that is a bit off on spec's or sloppy manufacture.
For me, it's difficult to accept a dealer telling me that 1 quart every thousand miles on a new car is normal. I just overhauled my 30 year oil Honda in my garage, farmed out the machine work and it does not burn a drop of oil between oil changes. My 03 Toyota 4Runner V8 at about 138K miles does not burn a drop between oil changes either.
I would extend the OCI if I were adding oil between changes but I would also invest in a UOA just to know for sure how the oil was doing.
For me, it's difficult to accept a dealer telling me that 1 quart every thousand miles on a new car is normal. I just overhauled my 30 year oil Honda in my garage, farmed out the machine work and it does not burn a drop of oil between oil changes. My 03 Toyota 4Runner V8 at about 138K miles does not burn a drop between oil changes either.
I would extend the OCI if I were adding oil between changes but I would also invest in a UOA just to know for sure how the oil was doing.
Originally Posted By: 901Memphis
What are his driving conditions? I ran my 3.1 about 6k miles on Pennzoil Platinum with some of heavy idle time and the TBN was in the upper 1.8 range so not much wiggle room for severe service. My engine doesn't consume oil though, that does boost the TBN.
These 3.1/3.4 engines are usually happy with 5k dino changes, but adding the extra oil should get him more mileage.
Your 1k mile extra for every quart is a solid hypothesis, just get a baseline uoa at 5k and another one after 8k to verify.
I am not sure of his driving conditions, I'd say during the week maybe 30-400 miles. I think he mentioned an oil pan gasket that's leaking, I don't think it burns a significant amount. He also said he uses whatever oil is on sale!
What are his driving conditions? I ran my 3.1 about 6k miles on Pennzoil Platinum with some of heavy idle time and the TBN was in the upper 1.8 range so not much wiggle room for severe service. My engine doesn't consume oil though, that does boost the TBN.
These 3.1/3.4 engines are usually happy with 5k dino changes, but adding the extra oil should get him more mileage.
Your 1k mile extra for every quart is a solid hypothesis, just get a baseline uoa at 5k and another one after 8k to verify.
I am not sure of his driving conditions, I'd say during the week maybe 30-400 miles. I think he mentioned an oil pan gasket that's leaking, I don't think it burns a significant amount. He also said he uses whatever oil is on sale!
Originally Posted By: OneEyeJack
If the oil is going somewhere it might be working harder than expected. This could be from hard driving, difficult conditions, a PCV problem or an engine that is a bit off on spec's or sloppy manufacture.
For me, it's difficult to accept a dealer telling me that 1 quart every thousand miles on a new car is normal. I just overhauled my 30 year oil Honda in my garage, farmed out the machine work and it does not burn a drop of oil between oil changes. My 03 Toyota 4Runner V8 at about 138K miles does not burn a drop between oil changes either.
I would extend the OCI if I were adding oil between changes but I would also invest in a UOA just to know for sure how the oil was doing.
I would invest in UOA just because its a GM 3400. That says everything I need to know, right there.
If the oil is going somewhere it might be working harder than expected. This could be from hard driving, difficult conditions, a PCV problem or an engine that is a bit off on spec's or sloppy manufacture.
For me, it's difficult to accept a dealer telling me that 1 quart every thousand miles on a new car is normal. I just overhauled my 30 year oil Honda in my garage, farmed out the machine work and it does not burn a drop of oil between oil changes. My 03 Toyota 4Runner V8 at about 138K miles does not burn a drop between oil changes either.
I would extend the OCI if I were adding oil between changes but I would also invest in a UOA just to know for sure how the oil was doing.
I would invest in UOA just because its a GM 3400. That says everything I need to know, right there.
The new V8 GMC engines hold 8 liters of oil and normal consumption
is said to be one liter per 1,600 km (1,000 miles) using 5W20.
At the 6,000 mile mark you already have added 5 liters of oil
and the dipstick shows "add".
Instead of changing the oil at this point, you change only the
filter and add 1.5 liters of oil.
What is the true age/mileage of the oil?
is said to be one liter per 1,600 km (1,000 miles) using 5W20.
At the 6,000 mile mark you already have added 5 liters of oil
and the dipstick shows "add".
Instead of changing the oil at this point, you change only the
filter and add 1.5 liters of oil.
What is the true age/mileage of the oil?
The GM 60-degree V6's and even the 3800 V6 engine, are amongst the 'easiest' on oil engines built in the past 25 years. I have almost 45k miles on mine since its last oil change. Oil related failure is practically unheard of. So don't fret about running a few thousand miles over the "official" interval providing all other maintenance is done on schedule and those intake gaskets aren't leaking coolant.
Seriously though, a quart in 2k miles is severely abnormal for that engine. I'd be very acutely worried that there's some other issue with the engine that hasn't been addressed before giving out 'advice' or 'recommendations'.
Seriously though, a quart in 2k miles is severely abnormal for that engine. I'd be very acutely worried that there's some other issue with the engine that hasn't been addressed before giving out 'advice' or 'recommendations'.
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