OIl Grade Suggestion for 300k 6.0L Chevy..
- Thread starter RcClockman
- Start date
Last Chev truck I had used about 6 qts in 250hrs (maybe 7000ish miles). Many many loads with 5 tons in the bed.
HAHA, This is how i went 260K on the original Brakes!
Back with an Update Guys! So I went on a 4000 mile roadtrip with my Truck, starting in Los Angeles, went to Yellowstone. Mount Rushmore, Zion, thru vegas and back home while Pulling my 30ft Travel trailer.. Trip stated with 308,000 miles, and As i always change oil at the 5000 mile marks, 5,10,15K ect... I knew i would have to change my oil halfway on the trip somewhere, and I did it myself one night during a overnight stay at a walmart parking lot in Idaho.... This walmart had a oil change/tire lube in it, but i didnt want to unhitch, and had nothing else better to do, i went in and bought the filter and oil and a pan and oil filter wrench. towels ect..
So the oil that i changed out was Mobil 1 15w-50 that preformed very well as far as my oil consumtion was concearned, It used about a quart every 1500-1750 miles vs 1 quart every 1000 miles that 10w-30 was using and also 15w-40 Chevron Delo full syn....
So i i stated before the 15w-40 does give much more oil pressure than the 10w-30 did, but burned the same amount of oil...
The 15w-50 oil pressure is exactly the same as 15w-40, but burnes less oil....
So i wanted to confim all this in my mind and went back to 15w-40 full synthetic Delo for the remaing half of the trip, and yes the oil pressures were the same, and the oil consumtion went way up....
I was worried about trip from about a month before i started, thing i was going to blow my engine on what ended being the HARDEST tow i have ever done especially leaving the east entrance of yellowstone on my way to mount rushmore, but the Truck ran cool the whole time, spent a lot of time in 2nd gear climbing big mountains, Trans temps would go up but never got in the red zone, and cooled back down to normal as soon as i got over the hills... and only issue i had with teh truck was a "Check engine soon" code at the near the end of my trip for a Bank2 sensor2 O2 sensor that hasent been changed out in a long time anyway...
As my wife endlessly keeps nagging me to buy a new truck I pointed out many reminders to her why i wont as we drove past many of new broken down Fords on the side of the road...
So i was averaging about 7.6 mpg pulling the 8000lbs trailer, using 91 gas , banks power programmer set to tow mode..
So i know i had many suggestion to get a new engine, ect... but just wanted to tell you all, I made it, yes engine is getting louder at idle as it get older with timing chain and or valve train noises, but she keeps pressing on, ... Perhaps i will try 20w-50 on the next change and report back next summer....
So the oil that i changed out was Mobil 1 15w-50 that preformed very well as far as my oil consumtion was concearned, It used about a quart every 1500-1750 miles vs 1 quart every 1000 miles that 10w-30 was using and also 15w-40 Chevron Delo full syn....
So i i stated before the 15w-40 does give much more oil pressure than the 10w-30 did, but burned the same amount of oil...
The 15w-50 oil pressure is exactly the same as 15w-40, but burnes less oil....
So i wanted to confim all this in my mind and went back to 15w-40 full synthetic Delo for the remaing half of the trip, and yes the oil pressures were the same, and the oil consumtion went way up....
I was worried about trip from about a month before i started, thing i was going to blow my engine on what ended being the HARDEST tow i have ever done especially leaving the east entrance of yellowstone on my way to mount rushmore, but the Truck ran cool the whole time, spent a lot of time in 2nd gear climbing big mountains, Trans temps would go up but never got in the red zone, and cooled back down to normal as soon as i got over the hills... and only issue i had with teh truck was a "Check engine soon" code at the near the end of my trip for a Bank2 sensor2 O2 sensor that hasent been changed out in a long time anyway...
As my wife endlessly keeps nagging me to buy a new truck I pointed out many reminders to her why i wont as we drove past many of new broken down Fords on the side of the road...
So i was averaging about 7.6 mpg pulling the 8000lbs trailer, using 91 gas , banks power programmer set to tow mode..
So i know i had many suggestion to get a new engine, ect... but just wanted to tell you all, I made it, yes engine is getting louder at idle as it get older with timing chain and or valve train noises, but she keeps pressing on, ... Perhaps i will try 20w-50 on the next change and report back next summer....
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That's interesting !! I'm running Pennzoil 10W-40 full syn and some STP SAE 30 in my 01 5.3 with 245K miles and never have to add any oil?? My oil pressure around 60PSI on full throttle
Running this for summer heat. Then going to either Pennz platinum 10W-30 or Delo 400XLE 10W-30 synblend for winter months
I really want to quote a certain catch phrase from the show The Office, right now.Thicker is better!..... Always!
Debated about running thicker in our 04 6.0L with 114k since it runs hot pulling 13k around. But it doesn’t consume anything measurable even though its seeping from a couple places, need to figure that out. Been running PUP 5w30 for 11 years at year intervals. Did notice lower oil pressures with AC Gold/Professional filter vs the regular, 10-20 less. Interesting to how a 6L ages RcClockman.. No idea how long we’ll keep our Class C but the max will be 200k so may never have issues.
20w-50 Chevron oil going in this week getting ready for a camping trip for next week, ill come back with my oil PSI numbers and consumtion after 2000 miles in a month.... Im at 325,000 miles now BTW...
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Not all esters clean. POE, Redline’s claim to fame, is a notoriously poor cleaner.
You need the correct esters, and alkylated napthalenes help. OP could run a couple quarts of HPL EC (which are the correct esters but no ANs) to see if there’s stuff to be cleaned. OP should do max 5k filter changes until filter analysis shows no more carbonaceous material in the pleats.
I'm close to this and my truck likes the 5w40 liqui moly
I bought my truck used and it has 228k miles now. I've done two engine flushes with BG EGR and could 100% tell it cleaned it out. Stuffs great. Haven't tried the seafoam.
OK, So got some miles now on the 20w-50...My Psi is really good, for my engine, 42.5 Hot Psi while Towing on Freeway at 3000 rpm's..Hot Idle at 25psi.... using about 1 quart per 1500 miles.... So far results are excellent... Also, my very first full tank of gas, not towing, i got my best MPG ever for some reason! was able to go 460 miles on a 34 gallons... 13.5 mpg is amazing on a 6.0 with 33's and a 4:56 rear end, normally I average around 11... so much for thicker oil gives you less mpg... Is it possible that my compression is better giving me more power and my foot is in the throttle less?
Only 25 psi hot idle with 20w-50? At hot idle with 15w-40 I never see the needle go below 30. Maybe that thick oil is helping with compression and efficiency more so than it can hurt it but I don't know for sure. I wonder if all that engine braking you did wore your engine out much faster. My 341k lq4 6.0 has almost stopped burning since my first reply on here in jan 2023. After 5k miles it only went down 1-1.5 quarts and I never stopped using 15w-40 nor did I ever get around to putting the updated valve cover on it so maybe it finished cleaning my dirty oil control rings.
I was wrong! Its actually 32.5 PSI hot idle, checked today after a 1 hour drive....
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What oil took you to 300k miles? Just stick to that.
Really amazing update. Thanks for sharing your continued experiments.
You might be beyond help with Valvoline Restore and Protect, but it would be interesting to see what happens with it or running HPL EC for a few oil changes and seeing if that helps.
You could also run a bottle of BG EPR right before you change your oil and see what you get. I've heard of some good results with that.
I usually put in a Bottle of MMO 250-500 miles before my oil change to help loosen and clean the engine up as my oil come out pretty black at 5000 mile intervals.....
Mobil 1 10w-30 up until 275,000 miles is when the engine really started to burn up oil and loose oil Psi... From that point is when I have gone up in thickness gradually with better results as I have gone thicker and thicker for the last 50,000 miles....Engine runs very strong..
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Root cause of burning oil?
