Oil Viscosity ?
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Topic: Oil Viscosity ?
Posted By: FREEDGUY
Subject: Oil Viscosity ?
Date Posted: 05 Dec 2020 at 6:36pm
| Can a heavier weight oil be introduced into a 5.4 Ford engine with 180K+ miles that uses 2 qts. between oil changes ? I'm currently using 5W20 conventional BTW. Thanks. |
Replies:
Posted By: Hubert (Ga)engine7
Date Posted: 05 Dec 2020 at 10:04pm
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With over 230K I am still using the Motorcraft 5w20 synthetic blend except when I messed up and bought a few quarts of 5w30 for top offs. I was losing around 2 quarts between changes but found it had a small leak at the pressure sending unit, now it uses about a quart on 5K change intervals. 99 F150 with 5.4. The 5wXX lubes better on startup than a thicker oil. Personally I would stay with the recommended oil. ------------- Just an old country boy saved by the grace of God. |
Posted By: steve(ill)
Date Posted: 05 Dec 2020 at 10:42pm
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You could change to 5w30 and still have the low viscosity for winter use. If you wanted to use 10w30 next summer, that would not be a problem. .... your motor is a 2005 or 6 which has the VCT system... It has small oil ports for the controls.. It dont like "thicker" oils.
Hubert is right.. Look around the oil pan and valve cover areas for a small leak.. Normally they dont "burn" that much oil. ------------- Like them all, but love the "B"s. |
Posted By: tom51
Date Posted: 06 Dec 2020 at 12:08pm
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Had a 97 F-150 with a 4.6 used a quart every 2500 miles was using 10w-40. Switched to 15-40 at 175k reduced oil consumption considerably between oil changes (5000) miles dry engine no leakes sat outside no trouble starting in winter (live in wi.). Ran it like that till I got rid of it (over 300k miles).
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Posted By: FREEDGUY
Date Posted: 06 Dec 2020 at 4:37pm
There are "weeps" of oil film on the underside of bell housing when I perform my 4000 mile oil change, but NO oil spots/drips under it ever  . The conventional isn't horribly priced to keep topping off, synthetic $$ would make me think twice about what route to go in the near future though  . Thanks guys
Yes, this is an '05 model
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Posted By: Coke
Date Posted: 06 Dec 2020 at 9:56pm
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Is it safe to switch from conventional to synthetic on an old engine? I was told switching to synthetic may soften up older hardened seals and cause more leaks? Don't know if that is apocryphal or not. ------------- 1957 D17 Diesel w/ M&W Pistons |
Posted By: Tbone95
Date Posted: 07 Dec 2020 at 7:22am
| Synthetics flow very well, and maintain that flow spot on to their viscosity rating. Putting them in an older engine may also do some cleaning, in some ways cleaning that may be more than the old girl can handle (dissolving deposits that mask or slow down leaks and weeps). But aren't "hardened" seals more likely to leak than a soft one? Maybe in the end we're kind of saying the same thing. |
Posted By: Roger (NE)
Date Posted: 07 Dec 2020 at 7:35am
| Might try Valvoline Max life in the same viscosity you're using now. Have had good luck with it reducing oil consumption in high mileage engines. Seems to have an additive that helps over time. |
Posted By: FREEDGUY
Date Posted: 07 Dec 2020 at 6:05pm
| Thanks Roger, I use Super Tek High Mileage oil already. |
Posted By: Ray54
Date Posted: 07 Dec 2020 at 8:24pm
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There are some that think it is very important to not change brands, it never has bothered me. I try to buy what is on sale, not that much has been on sale the last few years. The best starting and pulling for my old Cat D6's burns a 1/2 to 3/4 gal of oil in day. Been using Shell Rotula or TSC brand. But came across a sale on Delo 400 ,tractor burns about half as much per day on it. And that is only adding a gallon to the 4 that is already in it. So if the idea of mixing brands does not scare you, try different oils it may like one brand better. I have had people tell me of this before, but the first time I ever saw this much reduction.
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Posted By: FREEDGUY
Date Posted: 07 Dec 2020 at 8:25pm
| Thanks Ray |