Best synthetic oil to clean a dirty engine?
- Thread starter mattyice2
- Start date
Synthetic oil isn't going to clean a dirty engine (i.e. carbon deposits).
You really stand nothing to gain by running synthetic in a 4.0. These engines have more in common with a tractor than Ferrari.
Seriously though, synthetic engine oil in a 4.0 is nothing but a waste of money. Some won't want to believe it, but I promise, it's the cold hard truth.
How do you figure that your engine is "dirty"? And what does "dirty" entail?
You really stand nothing to gain by running synthetic in a 4.0. These engines have more in common with a tractor than Ferrari.
Seriously though, synthetic engine oil in a 4.0 is nothing but a waste of money. Some won't want to believe it, but I promise, it's the cold hard truth.
How do you figure that your engine is "dirty"? And what does "dirty" entail?
OP
Just bought the Jeep it has 135,000 miles. When I bought it they did a fresh oil change. After 1,000 miles the oil is pretty dark which makes me think the engine is dirty. What about semi synthetic then?
I'd give it a couple of oil changes at similar mileage, you're not pulling all of the oil from the engine at a change so if you want very clean you need to do a few flushes with clean oil to dilute the old oil still in the engine.
Personally, I run a synthetic more for the fact that modern synthetics are just a better oil. There's no performance gains to be had, but I'd like to think that it's looking after the engine a little better. Normally it's no more expensive either if you hit the sales at the auto store, what have you got to lose.
I always ran Shell Rotella 15/40. It's got a lot of detergents, and permanently eliminated the 4.0 lifter tick. I know a lot of people are gonna say that it's too thick , but that motor runs and sounds perfect at 145000 miles. I've been using Rotella since about 50000 miles.
TJ2
TJ Expert
That is too heavy of a viscosity, it's just too hard to pump through some of the small oil journals inside the engine. There are reasons Jeep engineers, the factory service manual, and owner's manual all recommend either 5W-30 or 10W-30 and nothing heavier. I dunno why some don't believe such recommendations don't apply to them. And lower viscosity oils get through all parts of the engine more quickly during the first start of the day when most engine damage occurs. A 15W would take longer to get through everything during that first cold start of each day. I sure as hell wouldn't run a 15W-40. No effing way.
In fact, because the first start of the day is so damaging that electric pre-oilers are commonly used in expensive engines, especially aircraft engines, to get the oil circulated before the engine is started. Which is why running a higher than recommended viscosity oil is just nutso to me. A Mobil oil engineer once told me the same thing and personally recommended a 5W-30 since it is easier/faster to get all through the engine during that critical/most damaging first start of the day.
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I have always run a motor flush through my engine when I do the first oil change (used cars), I also run some seafoam through the intake and also in the oil for a couple hundred miles (do this at a different oil change than the motor flush). I know there are a lot of people that say don't do this for what ever reason....but I have never had a problem with it on older or newer cars, If for nothing else the motor flush forces you to change the oil while engine is warm and at least thins the oil out so it will flow out of the pan better taking crud with it.
Sea Foam in the engine oil is just a bad idea. I sure as heck would not put Sea Foam in the engine oil, ESPECIALLY for a couple hundred miles.
I agree with the good advice in this thread. Dino oil and 10w-30.
One thing not mentioned, if it’s dirty, run your RPM’s up to blow out carbon deposits. It’s not good for engines to run at low RPM’s all the time. People think they are babying their engine and extending its longevity, but they’re actually allowing the engine to build up carbon deposits and destroying longevity. Don’t hesitate to run it up to 3500-4000RPM often.
I do think your darker oil comes from the blend of oils. Especially if the previous owner stops on Gooffy Lube and you went and pick the best on top of the shelf.
xackley
TJ Enthusiast
I would side with Seafoam for 100 miles then change your oil and filter. Then dyno oil. Also dump some in the gas tank.
Seafoam the air intake, oil, and gas only one time, one can, then the engine will be as clean as it can get it. If the engine doesn't need it, no harm done and you are out $10.
Seafoam the air intake, oil, and gas only one time, one can, then the engine will be as clean as it can get it. If the engine doesn't need it, no harm done and you are out $10.
If one simply must "clean" one's engine with motor oil, try Shell Rotella T5 synthetic blend 10w-30. (Rotella T4 "Triple Protection" and Rotella T6 full synthetic are also available in 10W-30, but in my humble opinion these won't work any better as an "engine cleaner" and full synthetic motor oil is a waste of money in a Jeep motor unless one is a believer in extended oil change intervals and drives one's jeep substantially more miles each year than the typical jeeper.)
Motor oils formulated for diesel engines typically have more detergent additives than motor oils formulated for gasoline engines, but more importantly some of the additives in diesel motor oils are better able to keep carbon and other contaminants in suspension which means that more of those contaminants are drained out at oil changes. (Another motor oil favored by vintage air-cooled VW enthusiasts for its ability to keep carbon in suspension is ordinary Valvoline 30 weight.)
Many people have reported benefits from using Rotella T5 in gasoline engines but you should be aware that there are also reports of Rotella "causing" new ticks and noises. However, there is no way to verify any of the anecdotal stories of deleterious effects, and I am highly suspect of claims that any top branded motor oil with the usual industry certifications caused damage to the internal parts of any engine.
Another benefit to Rotella touted by its users in jeeps is that it still contains ZDDP, an anti-wear zinc additive beneficial for motors with flat tappets like the jeep 4.0. ZDDP is no longer used in most motor oils designed for gasoline engines due to emissions restrictions.
To OP:
If I were in your position and wanted to experiment with a motor oil better able to remove deposits in the crankcase and oil passages I would use Rotella T4 10w-30 rather than Mobil 1 or any other synthetic motor oil. My thinking is that two hot oil changes at 3,000 mile intervals should be sufficient to determine whether it is beneficial. Couple that with a heavy dose of Lucas Upper Cylinder Lubricant and Injector Cleaner or Chevron Techron in the fuel tank at each oil change and regular spirited driving at higher RPM's to "blow out the crud" and call it a day.
______________
P.S.
I would not use Seafoam on a computer controlled engine or one equipped with catalytic converters because the concentrated detergents in Seafoam are hard on cats and some sensors. However, I have successfully used Seafoam in older engines without any adverse effects. It was a common practice "back in the day" and quite entertaining to watch the billowing clouds of white smoke come out of the tail pipe as you poured Seafoam down the intake.
My oil of choice for my jeep is Valvoline Maxlife 10w-30, a synthetic blend marketed for higher mileage engines. I am currently using a Fram Tough Guard filter, although my usual "go to" filter is Wix or NAPA Gold (make by Wix). I have the oil tested by Blackstone Labs every other oil change. Blackstone suggests that I can increase my oil change intervals to 7,500 miles based on the test results, but I intend to stick to 5,000 miles or every six months, whichever is first.
Motor oils formulated for diesel engines typically have more detergent additives than motor oils formulated for gasoline engines, but more importantly some of the additives in diesel motor oils are better able to keep carbon and other contaminants in suspension which means that more of those contaminants are drained out at oil changes. (Another motor oil favored by vintage air-cooled VW enthusiasts for its ability to keep carbon in suspension is ordinary Valvoline 30 weight.)
Many people have reported benefits from using Rotella T5 in gasoline engines but you should be aware that there are also reports of Rotella "causing" new ticks and noises. However, there is no way to verify any of the anecdotal stories of deleterious effects, and I am highly suspect of claims that any top branded motor oil with the usual industry certifications caused damage to the internal parts of any engine.
Another benefit to Rotella touted by its users in jeeps is that it still contains ZDDP, an anti-wear zinc additive beneficial for motors with flat tappets like the jeep 4.0. ZDDP is no longer used in most motor oils designed for gasoline engines due to emissions restrictions.
To OP:
If I were in your position and wanted to experiment with a motor oil better able to remove deposits in the crankcase and oil passages I would use Rotella T4 10w-30 rather than Mobil 1 or any other synthetic motor oil. My thinking is that two hot oil changes at 3,000 mile intervals should be sufficient to determine whether it is beneficial. Couple that with a heavy dose of Lucas Upper Cylinder Lubricant and Injector Cleaner or Chevron Techron in the fuel tank at each oil change and regular spirited driving at higher RPM's to "blow out the crud" and call it a day.
______________
P.S.
I would not use Seafoam on a computer controlled engine or one equipped with catalytic converters because the concentrated detergents in Seafoam are hard on cats and some sensors. However, I have successfully used Seafoam in older engines without any adverse effects. It was a common practice "back in the day" and quite entertaining to watch the billowing clouds of white smoke come out of the tail pipe as you poured Seafoam down the intake.
My oil of choice for my jeep is Valvoline Maxlife 10w-30, a synthetic blend marketed for higher mileage engines. I am currently using a Fram Tough Guard filter, although my usual "go to" filter is Wix or NAPA Gold (make by Wix). I have the oil tested by Blackstone Labs every other oil change. Blackstone suggests that I can increase my oil change intervals to 7,500 miles based on the test results, but I intend to stick to 5,000 miles or every six months, whichever is first.
badlieutenant
TJ Addict
The only reason I use synthetic oil in my Wrangler is because of the longer oil change times... that, and I haven’t experienced any bit of oil burn or leakage. The dipstick reads the same when I first change it till the next change, which is extended because I don’t drive it much.
I had a tick, at start up. Immediately, turn the motor off, an restart an tick would leave. I thru some synthetic in, with some seafoam, an i think a splash of mystery oil, an the tick everytime has gone, heard it once in the last twenty start ups. I felt like a chemical experiment. Will drain it here shortly. I put synthetic in another car, leaking oil worse around the oil pan gasket i was gonna change. I got some of that autorx stuff, an will throw that in the jeep, an will throw a camera into the cyclinders, to see what that does, before an after. will post it. later. an the jeeps got about 180000 on it.
I have a question. What is the recommended oil weight in the TJ Export Models owner's manual? Export to places like Mexico, South America, UAE, Austrailia, etc?
I tried to find an "export" owners manual, but so far no luck. Every manual I have specifies "API certified for gasoline engines" 10w-30.
If someone has a link to an "export" manual listing 15w-40 as an acceptable viscosity please publish a link. Having access to Jeep literature approving 15w-40 in our TJ's and LJ's would put an end to claims that 10w-30 is the only correct oil for our Jeeps.
If someone has a link to an "export" manual listing 15w-40 as an acceptable viscosity please publish a link. Having access to Jeep literature approving 15w-40 in our TJ's and LJ's would put an end to claims that 10w-30 is the only correct oil for our Jeeps.
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