High mileage or full synthetic oil?

I'm one those brand loyal nuts.
I run Castrol synthetic in everything from lawn mowers, pressure washer, Generator and every vehicle in the driveway. Lol
 
I've run valvoline conventional 10w30 it's whole life with a stock mopar filter, changed every 3K. If it was a finely tuned sports car I'd consider synthetic oil, but the 4.0 is a glorified tractor motor. But I've found that conventional valvoline contains 800 ppm of ZDDP per quart, so I'll be substituting a couple quarts of VR1 10w30 conventional race oil, which has 1400 ppm ZDDP to protect the flat tappet cam.
 
GASnBRASS said:
so I'll be substituting a couple quarts of VR1 10w30 conventional race oil, which has 1400 ppm ZDDP to protect the flat tappet cam.
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I've been waiting for 20 years of running TJs for someone to talk first-hand about having personally needed to replace a failed camshaft or lifters from running standard engine oils that all contain less zinc than used to be in oils.

The fact of the matter is the zinc content isn't a factor with a stock low-compression (glorified tractor engines ;) engine with standard valve springs. If I was running a high-performance engine with an aftermarket cam with stiffer valve springs I'd definitely want more zinc. But for a stock engine, it's a non-issue. In the multiple (!!) Jeep forums and news groups I've frequented since 1996, I've yet to read of a single Jeep owner with a stock 4.0 engine that had a camshaft failure. It doesn't happen. Which means the zinc issue is a greatly exaggerated (non) issue for us stock engine owners.

I'd love for someone to provide a link to a single failed standard low-compression Jeep 4.0L camshaft proven to have been caused by using a modern multi-weight oil.

Not to mention my daily-driver high-compression BMW and Lexus engines don't have camshaft problems with standard motor oils either. ;)
 
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Chris, Jerry, others .......
Just curious ...... you've referred to odometer readings as " 3k miles ..... 2k miles ..... 6k miles ..... etc."
Is the 'k' you refer to a reference to 'kilometers' .... ?
If that's the case, which is it ? ............. 6,000 km = 3725 miles, etc., etc. .....
Being a Canuck, our odometers/speedometers are calibrated in kilometers ......... (smiles) !!
 
Head Lice said:
Chris, Jerry, others .......
Just curious ...... you've referred to odometer readings as " 3k miles ..... 2k miles ..... 6k miles ..... etc."
Is the 'k' you refer to a reference to 'kilometers' .... ?
If that's the case, which is it ? ............. 6,000 km = 3725 miles, etc., etc. .....
Being a Canuck, our odometers/speedometers are calibrated in kilometers ......... (smiles) !!
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When we say 6k miles, we mean 6k miles... why would you believe adding a 'k' which simply means kilo which means thousand would change the miles word to meters? We did not say k meters... we said k miles. :)
 
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Jerry Bransford said:
I've been waiting for 20 years of running TJs for someone to talk first-hand about having personally needed to replace a failed camshaft or lifters from running standard engine oils that all contain less zinc than used to be in oils.

The fact of the matter is the zinc content isn't a factor with a stock low-compression (glorified tractor engines ;) engine with standard valve springs. If I was running a high-performance engine with an aftermarket cam with stiffer valve springs I'd definitely want more zinc. But for a stock engine, it's a non-issue. In the multiple (!!) Jeep forums and news groups I've frequented since 1996, I've yet to read of a single Jeep owner with a stock 4.0 engine that had a camshaft failure. It doesn't happen. Which means the zinc issue is a greatly exaggerated (non) issue for us stock engine owners.

I'd love for someone to provide a link to a single failed standard low-compression Jeep 4.0L camshaft proven to have been caused by using a modern multi-weight oil.

Not to mention my daily-driver high-compression BMW and Lexus engines don't have camshaft problems with standard motor oils either. ;)
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And in the same token a little pre-emptive care can't hurt either. :) Frequent oil changes with the right oil are a heck of alot cheaper and easier than a motor rebuild.
 
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Since it's the first oil change, I'm assuming you don't know what oil is in there now, I would run any name brand 10/30 previously mentioned. If the valve train remains quiet, then keep using that oil..... don't change brand. I found that my valves would clatter or not clatter just by going to a different brand of the same viscosity. After 5 yrs. and several oils, the only one the keeps it quiet between 4000 mile intervals is Shell Rotella 15/40. I bought my Jeep with 70,000 miles, and it now has 126,000, quiet for about the last 24,000. Not recommending, just saying what works for me.
 
all I know is that after my first oil change putting in Mobil 1 high mileage i developed a RMS leak. it was bone dry up to that oil change. I have no idea what was in it from prior owner but had no leaks before the oil change.
before I bought the Jeep it was on the lot (very small dealer who just sells jeeps and has no more than 4 or 5 at any given time) for about a month. Often times I went over after hours to check it out,check frame over and over, and also looked for leaks and there was no drips hanging down, no oil spots on ground and the jeep was in the same spot for weeks.

got it home, put about 1k miles on it, still no leaks and did my mobil 1 oil changed and within a week, it started leaking. I know they say using synthetic does not cause leaks but with the timing and all, not a coincidence. maybe the synthetic oil did a great job at cleaning out the gunk that was keeping it from leaking but my last oil change I went to Pennzoil high mileage dino.

not saying mobil 1 is bad , i use it in my mustang but that only has 34k miles on it.
 
Does anyone know what the difference is between the High Mileage and regular oil is ? I went from regular oil, to Rotella, to Mobil 1 high mileage.

Getting ready for another oil change, just curious which is better/difference, want to make my motor happy. Just drove from Colorado, over the rockies to Santa Barbara, to Anaheim (with my SJ Sharks tire cover, sorry Duck fans) then back to Santa Barbara, and up to Napa, Cal. The Jeep ran awesome and solid, so time to reward it :)
Thanks
Ray
 
Jerry Bransford said:
X2, just change the oil and filter and you'll be fine no matter what oil you use. I don't believe in 3,000 mile intervals though, that short of an interval for normal driving didn't come along until Jiffyworld started pushing that interval for obvious reasons. I stick with every 5k miles and conventional motor oils which have worked well for me the last 50+ years, never an engine problem. Though if I lived where it got uber cold during the winter like upstate NY, Minnesota, Alaska, etc. I'd definitely pay extra to run a synthetic during the winter.
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Not disputing you, Jerry, but I could swear the 3000 mile thing went back to the 70, s. I thought the intervals gradually got longer as oil quality improved. I could be wrong.... at 57, that was a while back.
 
jeepXcore said:
Probably going to do my first oil change in the next few 100 miles. Not sure if I should go with a high mileage oil or a full synthetic. My TJ has 89,000 miles on it btw.[/QUOTE


I do believe synthetic oils are better than conventional (and it would seem that the car manufactures agree).
But unless you have some high performance motor and are using it for what that performance car was built for, conventional oils or semi synthetic oils will work just fine.
I have a 1992 Ford F-150 and have always used conventional oil. It now has 323,000. mile on it and doesn't burn or leak any oil. I've been changing the oil at around the 3000 mile mark and it's still on the full mark when I change it.
So no matter what kind or brand of oil you are using; :private: :private: :private: :private:
Oil is cheap engines are expensive change your oil regularly!! :bash:

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DC0046 said:
Agree with IronCity. My personal experience with my 04 with 72000 miles is when I changed to synthetic, my rear main developed a leak. Changed back to conventional oil with a quart of Lucas and after 300 miles, leak stopped. Will not be using synthetic in the Jeep in the future. Will see if no leaks when nothing but conventional oil is used at next change. Others on this forum have had the same experience.
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You know I never made the connection but mine started to leak when I converted over to syn oil. I will go back and see if it stops leaking.
 
Germanshepherd said:
all I know is that after my first oil change putting in Mobil 1 high mileage i developed a RMS leak. it was bone dry up to that oil change. I have no idea what was in it from prior owner but had no leaks before the oil change.
before I bought the Jeep it was on the lot (very small dealer who just sells jeeps and has no more than 4 or 5 at any given time) for about a month. Often times I went over after hours to check it out,check frame over and over, and also looked for leaks and there was no drips hanging down, no oil spots on ground and the jeep was in the same spot for weeks.

got it home, put about 1k miles on it, still no leaks and did my mobil 1 oil changed and within a week, it started leaking. I know they say using synthetic does not cause leaks but with the timing and all, not a coincidence. maybe the synthetic oil did a great job at cleaning out the gunk that was keeping it from leaking but my last oil change I went to Pennzoil high mileage dino.

not saying mobil 1 is bad , i use it in my mustang but that only has 34k miles on it.
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Same experience here.
 
WWII Jeeper said:
Does anyone know what the difference is between the High Mileage and regular oil is ? I went from regular oil, to Rotella, to Mobil 1 high mileage.

Getting ready for another oil change, just curious which is better/difference, want to make my motor happy. Just drove from Colorado, over the rockies to Santa Barbara, to Anaheim (with my SJ Sharks tire cover, sorry Duck fans) then back to Santa Barbara, and up to Napa, Cal. The Jeep ran awesome and solid, so time to reward it :)
Thanks
Ray
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High mileage has some seal conditioners and little extra additives for wear protection.
 
Jerry Bransford said:
Yes, that is when Jiffylube started... 1971.
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Crap....I didn't know Jiffy Lube was that old. I grew up on Long Island, and never saw them. I guess between helping my father doing oil changes as a kid, and growing up with a bunch of gear heads, I never knew anybody who took their car to get an oil change.
 
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