ford recommend 5-20 can i use 15-40
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I live in the NW corner of NJ. Winter temps can run below 0 F but are usually in the 20's to 30's for most of the winter except late Dec through Jan. My 1989 F-150 with the 4.9 six was spec'd for 10W-30 dino. It did not like dino 10W-30 in the real cold but started much faster and quieter on Mobil 1 10W-30. Unless your winter temps are not really below freezing I would not use the 15W-40. Save it for the late spring to early fall OCI.
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Originally Posted By: Panzerman
15w40 is made for mixed fleets which are gas and diesel. Use it, will see it is perfectly fine, summer or winter. I lived in Pennsylvania for 30+ years and we used 15w40 oil in everything, well below zero degrees without any problems or weird noises. Most people that reccomend aginst it have no experience to back thier opinion, other than what they believe "may" happen..
Oh, contraire, Herr Panzermann. I had a diesel tractor that WOULD NOT spin over quickly enough to start on 15W40 but would (and does) on 10W30.
Can you "use" 15W40 in engines spec'ed for 5W20? Sure. Is it optimal? No. Could it be harmful? Possibly, especially when viewed long term. Go to Widman's site and graph 15W40 vs a 5W20, view the results in context with the most likely range of climatic conditions. Unless a person lives in a very hot climate or uses the truck as a "maximum duty" workhorse, everyday in the summer, the oil will be running in the 50 grade. In winter it could be running as a 60 grade... or off the chart. Not sure I even want to speculate on cold weather flow (or lack thereof) in 20 and 30F temps. Typical 5W20 CCS is around 5300 cP @ -30 for a syn blend. A typical dino 15W40 is around 6500-7000 @ -20. Big diff in cold flow. You can narrow the gap with a syn 15W40, but not by all that much.
I would also mention that anyone that doesn't have a similar truck with a 4.2L V6 and has used 15W40 in it, especially thru winter, then they too are merely expressing an opinion on what "may" happen with the OP's truck.
To the OP: If you must use this oil in your truck, then the best time to do so is in the summer. Since the 4.2 has architecture based on the Windsor V8 engines, of all the newer Ford engines, you have the best chance of "getting away" with a heavy oil like that. But again, it's not optimal from the cold flow (and wear) department, as well as fuel economy. It's likely a two grade increase in viscosity is likely to show up in the MPG department, especially if you don't use it for long drives. The best way to make the most of an over-spec, heavy oil is to use it on long hauls, where the oil stays hot and relatively thin. IMO, lots of cold starts and short hops would be detrimental.
15w40 is made for mixed fleets which are gas and diesel. Use it, will see it is perfectly fine, summer or winter. I lived in Pennsylvania for 30+ years and we used 15w40 oil in everything, well below zero degrees without any problems or weird noises. Most people that reccomend aginst it have no experience to back thier opinion, other than what they believe "may" happen..
Oh, contraire, Herr Panzermann. I had a diesel tractor that WOULD NOT spin over quickly enough to start on 15W40 but would (and does) on 10W30.
Can you "use" 15W40 in engines spec'ed for 5W20? Sure. Is it optimal? No. Could it be harmful? Possibly, especially when viewed long term. Go to Widman's site and graph 15W40 vs a 5W20, view the results in context with the most likely range of climatic conditions. Unless a person lives in a very hot climate or uses the truck as a "maximum duty" workhorse, everyday in the summer, the oil will be running in the 50 grade. In winter it could be running as a 60 grade... or off the chart. Not sure I even want to speculate on cold weather flow (or lack thereof) in 20 and 30F temps. Typical 5W20 CCS is around 5300 cP @ -30 for a syn blend. A typical dino 15W40 is around 6500-7000 @ -20. Big diff in cold flow. You can narrow the gap with a syn 15W40, but not by all that much.
I would also mention that anyone that doesn't have a similar truck with a 4.2L V6 and has used 15W40 in it, especially thru winter, then they too are merely expressing an opinion on what "may" happen with the OP's truck.
To the OP: If you must use this oil in your truck, then the best time to do so is in the summer. Since the 4.2 has architecture based on the Windsor V8 engines, of all the newer Ford engines, you have the best chance of "getting away" with a heavy oil like that. But again, it's not optimal from the cold flow (and wear) department, as well as fuel economy. It's likely a two grade increase in viscosity is likely to show up in the MPG department, especially if you don't use it for long drives. The best way to make the most of an over-spec, heavy oil is to use it on long hauls, where the oil stays hot and relatively thin. IMO, lots of cold starts and short hops would be detrimental.
The major opinion here seems to be to not use it based on the winter temps in your area. There are options to include save it as oil has a good shelf life.
True story. I work for a large gov't fleet in the So Cal area. The fleet includes Ford's Crown Victoria's as well as other Ford models to include 1/2 ton thru 1 ton vans and trucks. We also have similar vehicles from GM, Chrysler, and imports. For over 20 years we have exclusively used a 15w-40 HDEO oil, and recently the oil is a reclaimed oil from a local petroleum supplier. To the best of my knowledge, we have never had an oil related problem that could be attributed to the viscosity of the 40 weight oil. Many of the vehicles have logged over 120k miles before being sold.
Not saying you should use the oil, but like I initially said, but you have options.
There is a viscosity calculator around here and one could plug in the data and see if you could "blend" it down to a safer 20 to 30 weight by using Shell's conventional white bottle. Just a thought.
SOPUS owns Shell, Pennzoil, and Quaker State, so these oils are probably mixeable if you feel you have to.
Hope this helps, Bill
True story. I work for a large gov't fleet in the So Cal area. The fleet includes Ford's Crown Victoria's as well as other Ford models to include 1/2 ton thru 1 ton vans and trucks. We also have similar vehicles from GM, Chrysler, and imports. For over 20 years we have exclusively used a 15w-40 HDEO oil, and recently the oil is a reclaimed oil from a local petroleum supplier. To the best of my knowledge, we have never had an oil related problem that could be attributed to the viscosity of the 40 weight oil. Many of the vehicles have logged over 120k miles before being sold.
Not saying you should use the oil, but like I initially said, but you have options.
There is a viscosity calculator around here and one could plug in the data and see if you could "blend" it down to a safer 20 to 30 weight by using Shell's conventional white bottle. Just a thought.
SOPUS owns Shell, Pennzoil, and Quaker State, so these oils are probably mixeable if you feel you have to.
Hope this helps, Bill
I had a 2002, 3 liter ford ranger which i used 5w20, 10w30, a few summer runs of 15w40. the 5w20 was motorcraft, 10w30 was synpower, and 15w40 was castrol. From april to nov with the 15w40 there was no noticeable difference in the engine except for being slightly quieter .In my opinion the truck seemed to run best on the synpower summer and winter. in the summer there really no noticeable difference in m.p.g between all of the oils.
I suggest you use the 5-20 as your main oil and use the 15-40 as top-off oil to keep the crankcase full. Also when you change your oil, use the 5-20 as the main stock but add one quart of the 15-40. If you have 5 qts. 5-20 and one of 15-40 the resulting mix is about a 6.6-23.3 which should be OK, would eventually use it up.
Originally Posted By: OVERK1LL
It'll work just fine. Not optimal, but I've run both 5w40 and 0w40 in my 5.4L and it worked just fine.
And that included a Canadian winter (where the 0w40 was noticeably better).
Just use it for summer OCI's.
Big, big difference between a 0wXX or 5wXX, and a 15w40. Every cold start in Ontario or New Jersey, in the winter, creates extra engine wear.
If the engine is plugged in when not operating, or parked in a heated space, and then driven all day without shutting it off, then a higher-viscosity oil like a 15w40 would be okay even in that climate. But otherwise, no.
It'll work just fine. Not optimal, but I've run both 5w40 and 0w40 in my 5.4L and it worked just fine.
And that included a Canadian winter (where the 0w40 was noticeably better).
Just use it for summer OCI's.
Big, big difference between a 0wXX or 5wXX, and a 15w40. Every cold start in Ontario or New Jersey, in the winter, creates extra engine wear.
If the engine is plugged in when not operating, or parked in a heated space, and then driven all day without shutting it off, then a higher-viscosity oil like a 15w40 would be okay even in that climate. But otherwise, no.
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Originally Posted By: Tornado Red
Originally Posted By: OVERK1LL
It'll work just fine. Not optimal, but I've run both 5w40 and 0w40 in my 5.4L and it worked just fine.
And that included a Canadian winter (where the 0w40 was noticeably better).
Just use it for summer OCI's.
Big, big difference between a 0wXX or 5wXX, and a 15w40. Every cold start in Ontario or New Jersey, in the winter, creates extra engine wear.
If the engine is plugged in when not operating, or parked in a heated space, and then driven all day without shutting it off, then a higher-viscosity oil like a 15w40 would be okay even in that climate. But otherwise, no.
Yes, there was a big difference between the two (I changed the oil in the middle of the winter). At -20, the truck started WAY better on the 0w40 than the 5w40.
Originally Posted By: OVERK1LL
It'll work just fine. Not optimal, but I've run both 5w40 and 0w40 in my 5.4L and it worked just fine.
And that included a Canadian winter (where the 0w40 was noticeably better).
Just use it for summer OCI's.
Big, big difference between a 0wXX or 5wXX, and a 15w40. Every cold start in Ontario or New Jersey, in the winter, creates extra engine wear.
If the engine is plugged in when not operating, or parked in a heated space, and then driven all day without shutting it off, then a higher-viscosity oil like a 15w40 would be okay even in that climate. But otherwise, no.
Yes, there was a big difference between the two (I changed the oil in the middle of the winter). At -20, the truck started WAY better on the 0w40 than the 5w40.
Do not use 15w40 use 5w30 in that 6 cylinder...
Dont forget the 5w20 or 5w30 runs cooler than the 15w40
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