Whats a good synthetic to run
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Joined: Aug 2001
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From: Houston, TX
I ran Motorcraft 5w20 until 15000 miles then switched to Royal Purple 5w20 and have been running that since. I have had no problems in this vehicle or any of my past vehicles using the same process.
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Joined: Oct 2002
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From: League City, TX
Nobody was asking for a criticism of the internal state of these engines or trying to "blame" anyone for not keeping up there engine, that's a different thread and a moot point here...they only wanted to know what the potential hazards of switching could be, how is that a "crock"?
Last edited by bridge; Jul 26, 2009 at 02:23 PM.
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Joined: Jul 2008
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From: Houston, Tx
Boy, is there a bunch of bad information coming out in this thread.
1. Running 10w30 over 85,000? Not necessary. 5w20 is good for the life of the engine provided it's been properly maintained. You don't have to stick to Motorcraft oil and filters.
2. Synthetic causing oil leaks and lack of lubrication? Bunk. If an engine develops a leak after switching to synthetic then it was going to leak anyway, regardless of what oil is in it. Sludge only develops when the oil isn't changed at the proper mileage intervals. Whatever sludge is in there isn't likely to move, unless a heavy duty cleaner is run through that's designed to break it down and move it. Switching to synthetic isn't going to do that.
3. This one's my personal favorite: extended change intervals with synthetic. Synthetic oil needs to be changed at the same mileage as conventional oil because it picks up the same amount of dirt over that 3-5000 miles. Oil filters are only designed to work for about 5000 miles, after that they clog up and the oil starts going through the bypass valve and back into the engine unfiltered. You can run a synthetic for 10,000 miles but the filter stopped working 5000 miles back. Yes, you could just change the filter and keep running the oil but why? Just so you can feel like your getting your money's worth? If you've already pulled the filter it's only a couple more steps to drain the oil. Oil is cheap when you compare it to the cost of a new engine.
I've already said this but it's worth repeating. People think too much about oil. Use any brand you prefer, use a good filter and change it at the proper intervals and that engine will go 200,000+.
1. Running 10w30 over 85,000? Not necessary. 5w20 is good for the life of the engine provided it's been properly maintained. You don't have to stick to Motorcraft oil and filters.
2. Synthetic causing oil leaks and lack of lubrication? Bunk. If an engine develops a leak after switching to synthetic then it was going to leak anyway, regardless of what oil is in it. Sludge only develops when the oil isn't changed at the proper mileage intervals. Whatever sludge is in there isn't likely to move, unless a heavy duty cleaner is run through that's designed to break it down and move it. Switching to synthetic isn't going to do that.
3. This one's my personal favorite: extended change intervals with synthetic. Synthetic oil needs to be changed at the same mileage as conventional oil because it picks up the same amount of dirt over that 3-5000 miles. Oil filters are only designed to work for about 5000 miles, after that they clog up and the oil starts going through the bypass valve and back into the engine unfiltered. You can run a synthetic for 10,000 miles but the filter stopped working 5000 miles back. Yes, you could just change the filter and keep running the oil but why? Just so you can feel like your getting your money's worth? If you've already pulled the filter it's only a couple more steps to drain the oil. Oil is cheap when you compare it to the cost of a new engine.
I've already said this but it's worth repeating. People think too much about oil. Use any brand you prefer, use a good filter and change it at the proper intervals and that engine will go 200,000+.
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Joined: Aug 2001
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From: Houston, TX
To me it idled a little smoother and ran a little better but I am sure that is all just in my head. The major reason for switching for me was longevity of the engine and less wear and tear not performance.
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Joined: Oct 2002
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From: League City, TX
For what it's worth, I started using Synthetic (mobile1 at the time) in my '01 Expedition which had started to consume a lot of oil between changes. It also seemed to quieten down these ticky modular engines. I've since switched to Pennzoil Platinum due to the lower price.
In reference to the switching oils discussion, I found this post from another thread referring to the same issue of adding a new fluid/oil with more detergent/cleaners causing problems. While it's a transmission thread it is still an applicable analog demonstrating the potential for problems.
https://www.f150online.com/forums/3817717-post13.html
In reference to the switching oils discussion, I found this post from another thread referring to the same issue of adding a new fluid/oil with more detergent/cleaners causing problems. While it's a transmission thread it is still an applicable analog demonstrating the potential for problems.
https://www.f150online.com/forums/3817717-post13.html
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Joined: Jun 2009
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From: College Station, TX
I am also running Royal Purple in my truck right now. As I have absolute zero complaints about the oil, I do not think it is near worth the price. I didn't notice an increase in HP (although there may have been a little, no dyno) and as far as running smoother compared to the conventional oil I was running before, not that big of a difference. The only difference I did notice is that the truck seemed to start slightly easier than before. But an oil change on an F150 for over $100 not counting my time and effort...it just wasnt worth it. Will be switching to Motorcraft in the next 1,000 miles.
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From: Texas Baby!!
But shortly after I switched the engine I swapped the Xfer, front diff & p/s on the '99 as well. Prior to the switch the p/s pump had been making a lot of noise and I figured I would be replacing it soon. After the switch it ran smooth and quiet, like a brand new pump.
With all fluids switched the truck was pretty consistent with a 1 mpg increase.
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Joined: May 2004
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From: san diego
I am also running Royal Purple in my truck right now. As I have absolute zero complaints about the oil, I do not think it is near worth the price. I didn't notice an increase in HP (although there may have been a little, no dyno) and as far as running smoother compared to the conventional oil I was running before, not that big of a difference. The only difference I did notice is that the truck seemed to start slightly easier than before. But an oil change on an F150 for over $100 not counting my time and effort...it just wasnt worth it. Will be switching to Motorcraft in the next 1,000 miles.
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How can I tell if my "pickup screen is clogged"?
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From: College Station, TX
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Joined: Aug 2009
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From: TX
Royal Purple here. I have noticed easier start and smoother running with it. Could have gotten that with other brands I am sure but tried RP and liked it. Lookin at around $75 for an oil change for me. Like previously said...just don't go cheap on the filter...especially if you let it go longer.
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From: Punta Gorda/ Boca Raton, FL
i cant even believe someone logically thought to say "do not use mobil1".
no one can accurately and consistently say that mobil1, or any oil for that matter, is 'bad".
with that said, i used castrol gtx in my TL for 80k miles, mobil 1 for 50k miles in my maxima, mobil one for the 20k in my truck, and mobil1 and motul synth in my 4 bikes (gsxr1000, r1, r6, and cbr600rr) for a combined 30k miles. never had any motor related issues, ever. and for the record, i beat the living **** out of all of my toys.
no one can accurately and consistently say that mobil1, or any oil for that matter, is 'bad".
with that said, i used castrol gtx in my TL for 80k miles, mobil 1 for 50k miles in my maxima, mobil one for the 20k in my truck, and mobil1 and motul synth in my 4 bikes (gsxr1000, r1, r6, and cbr600rr) for a combined 30k miles. never had any motor related issues, ever. and for the record, i beat the living **** out of all of my toys.