gdhillon
Full Access Member
I recently put Rotella synthetic 5w40 in my truck, is the oil to thin for warmer temps? And how much does the oil being synthetic increase the change interval ?( with avg normal city driving)
Synthetic 5w40....ok in summer temps?
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PwrSmoke
Full Access Member
Is 40 grade too thin? Not by a longshot! IMO, it's too heavy and I've run 10W30 HDEO in mine for decades, when I could get it (it was pretty hard in the '90s). Be happy; 5W40 is great for summer with the added bennie of great cold start specs.
As to interval, you can safely go longer but how much longer will depend on the soot load and fuel dilution. My oil analysis has shown it takes about 5.5K miles for the soot to get up to 0.4-0.6 percent. The condemnation level is upwards of 2 percent so I had a long way to go. The same test showed 1 percent fuel and the condemnation was 2 percent. This was an ordinary 10W30 CJ-4 oil but with a FL1995 Powerstroke style filter, which is a bit more efficient than the standard FL784. A lot will depend on your truck. I think 5K intervals are easily doable but you should get oil analysis done to see where your soot levels and fuel levels are at that time. I recommend Wear Check for oil analysis. My prescription for you would be to run 4K, test and then extend it as indicated. It really depends a lot on how you use your truck and whether it's modded and by how much. The only way to seriously extend the interval is by installing a bypass system, which will catch a lot of that soot and extend the interval by double or more (depending on the system. Just went to a Racor bypass on mine so I'm starting from scratch with my intervals (which have been 6K with a 3-year time limit... usually reached in 2 years). I suspect I'll be able to do 10-15K easy on Rotella T-5 but that remains to be proven.
I change my IH tractor oil at 120 hours (about 7000 miles equivalent). The oil is still great but the soot load is near 3 percent at that point. That's also a three year interval.
As to interval, you can safely go longer but how much longer will depend on the soot load and fuel dilution. My oil analysis has shown it takes about 5.5K miles for the soot to get up to 0.4-0.6 percent. The condemnation level is upwards of 2 percent so I had a long way to go. The same test showed 1 percent fuel and the condemnation was 2 percent. This was an ordinary 10W30 CJ-4 oil but with a FL1995 Powerstroke style filter, which is a bit more efficient than the standard FL784. A lot will depend on your truck. I think 5K intervals are easily doable but you should get oil analysis done to see where your soot levels and fuel levels are at that time. I recommend Wear Check for oil analysis. My prescription for you would be to run 4K, test and then extend it as indicated. It really depends a lot on how you use your truck and whether it's modded and by how much. The only way to seriously extend the interval is by installing a bypass system, which will catch a lot of that soot and extend the interval by double or more (depending on the system. Just went to a Racor bypass on mine so I'm starting from scratch with my intervals (which have been 6K with a 3-year time limit... usually reached in 2 years). I suspect I'll be able to do 10-15K easy on Rotella T-5 but that remains to be proven.
I change my IH tractor oil at 120 hours (about 7000 miles equivalent). The oil is still great but the soot load is near 3 percent at that point. That's also a three year interval.
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The recommended spec is 15w-40 or Streight 30Wt for summer use. Personally, I think 5wt would worry me a little. The oil presure tends to drop with heat anyway, and 5w is like water. These engines are not that tight and need a bit of viscosity in my opionion.
gdhillon
Full Access Member
Jim, that how do you check for soot levels? Do you send it to black labs (I'm forgetting the actual name).
What does the first number before the w 40 mean? Is it the viscosity?
So to keep an eye in things in warmer temps is to watch the oil pressure dummy gauge? is there another accurate gauge that can be swapped in it's place?
What does the first number before the w 40 mean? Is it the viscosity?
So to keep an eye in things in warmer temps is to watch the oil pressure dummy gauge? is there another accurate gauge that can be swapped in it's place?
PwrSmoke
Full Access Member
You are thinking of Blackstone, but they don't do a separate soot test, only "insolubles" (which includes soot and other stuff). Wear Check, and others, (Google them) will do a separate soot check. Another sign of soot is when the oil begins to thicken. Usually oil gets thinner as the VII (Viscosity Index Improvers) wear out but it reaches a stage when the soot starts to make it thicken. Most HDEO (Heavy Duty Engine Oil) resist thinning pretty well, at least the ones I've tried (Royal Purple, Delo 400 and various Rotellas). Interestingly, the first few years with my truck, I used the oil type Ford recommended, a SF/CC 10W30, in a Pennzoil brand.
As to "5W" or "10W" being "too thin" it does not apply to warm oil, as clayton said. The 40 grading is the warm viscosity taken at 100C (about 212F), and 40 grade can be as thin as 12.5 cST (Centistokes) or as thick as 16.2 cSt at that temp. A wide range. The only cold viscosity rating is the 40C (100F) spec, which is not shown in the grade.
I base my vioscosity choices on my running oil temps, which in my engine are seldom if ever above 190F. Oil thins as it gets hot and thickens as it gets cold. At 190F, 40 grade oil is running in 50 grade territory or at the extreme end of 40, so it's really thicker than the engine needs. The Rotella 10W30 I commonly use, which is thick in it's grade, is running as a 40 grade at that temp (at the low end of it, anyway). Also, a 15W40 doesn't flow well even on a cool start (say 65 degrees). The saving grace for our engines is that wonderful oil cooler, which warms the engine oil up quickly as the coolant warms and keeps it pretty close to coolant temp as oil temp rises above coolant temp. By using a viscosity calculator (Google "Widman" with "viscosity" and a good one will come up in Spanish or English) and entering in the 40C viscosity and 100C viscosity (from Product Data Sheets for the oil), and the temp you want to see, you can tell what viscosity the oil is running at any given temp. Anyway, by monitoring my engine oil temp for several years, I concluded that the factory recommendation (at least in my '86 manual- see the chart which came in my original owners manual) is correct. It may not be for everyone, because it directly relates to oil temp and how the truck is operated. Thicker oil than you need can accelerate cold start wear, put the oil filter into bypass on a cold start (no oil filtration), put the oil filter into bypass at high rpms or when the oil isn't fully warmed up and it can decrease fuel economy due to fluid friction. Basically you need oil as thick as it needs to be at that moment. If it's thicker you are wasting energy. If too thin, it can cause wear so that's why you need the RIGHT viscosity for the situation, not some arbitrary choice that someone says is better. If you have the right viscosity, thicker isn't better or offers any less wear. As to my choice, I can only say for sure that it's right for my truck... and it was right for Ford in 1986 for trucks that fit the operating parameters. Oil has improved a lot since then but the one part of the old recommendations that is still valid are the basic viscosity recommendations.
You can improve on those recommendations in the "W"area. The "W" designation is a cold weather performance specification not a direct indicator of viscosity. The W grading breaks down into the following specs under SAE J300:
0W- Cold Cranking Simulator test (CCS) no more that 6,200 cP @ -35C (cP = Centipoise, another measurement of viscosity)
5W- CCS < (the "less than) sign) 6600 cP @ -30C
10W- CCS< 7000 cP @ -25C
15W- CCS < 7000 cP @ -20C
20W- CCS < 9500 cP @ -15C
There are also MRV Cold Pumping Viscosity (MRV=Mini-Rotorary Viscometer) specs and minimum viscosities involved in the J300 specs, but it all comes down to how cold pumping specs for the oil. By choosing the lowest "W" number, you can improve the cold flow of the oil as well as the "cool" flow... the first start on a 60-70 degree day for example.
Also, I have run 15w40 in my truck on occasion and when I did I checked the warm (180F) oil pressure vs 10W30 and there was only a 5 psi difference at 2000 rpm.
As to "5W" or "10W" being "too thin" it does not apply to warm oil, as clayton said. The 40 grading is the warm viscosity taken at 100C (about 212F), and 40 grade can be as thin as 12.5 cST (Centistokes) or as thick as 16.2 cSt at that temp. A wide range. The only cold viscosity rating is the 40C (100F) spec, which is not shown in the grade.
I base my vioscosity choices on my running oil temps, which in my engine are seldom if ever above 190F. Oil thins as it gets hot and thickens as it gets cold. At 190F, 40 grade oil is running in 50 grade territory or at the extreme end of 40, so it's really thicker than the engine needs. The Rotella 10W30 I commonly use, which is thick in it's grade, is running as a 40 grade at that temp (at the low end of it, anyway). Also, a 15W40 doesn't flow well even on a cool start (say 65 degrees). The saving grace for our engines is that wonderful oil cooler, which warms the engine oil up quickly as the coolant warms and keeps it pretty close to coolant temp as oil temp rises above coolant temp. By using a viscosity calculator (Google "Widman" with "viscosity" and a good one will come up in Spanish or English) and entering in the 40C viscosity and 100C viscosity (from Product Data Sheets for the oil), and the temp you want to see, you can tell what viscosity the oil is running at any given temp. Anyway, by monitoring my engine oil temp for several years, I concluded that the factory recommendation (at least in my '86 manual- see the chart which came in my original owners manual) is correct. It may not be for everyone, because it directly relates to oil temp and how the truck is operated. Thicker oil than you need can accelerate cold start wear, put the oil filter into bypass on a cold start (no oil filtration), put the oil filter into bypass at high rpms or when the oil isn't fully warmed up and it can decrease fuel economy due to fluid friction. Basically you need oil as thick as it needs to be at that moment. If it's thicker you are wasting energy. If too thin, it can cause wear so that's why you need the RIGHT viscosity for the situation, not some arbitrary choice that someone says is better. If you have the right viscosity, thicker isn't better or offers any less wear. As to my choice, I can only say for sure that it's right for my truck... and it was right for Ford in 1986 for trucks that fit the operating parameters. Oil has improved a lot since then but the one part of the old recommendations that is still valid are the basic viscosity recommendations.
You can improve on those recommendations in the "W"area. The "W" designation is a cold weather performance specification not a direct indicator of viscosity. The W grading breaks down into the following specs under SAE J300:
0W- Cold Cranking Simulator test (CCS) no more that 6,200 cP @ -35C (cP = Centipoise, another measurement of viscosity)
5W- CCS < (the "less than) sign) 6600 cP @ -30C
10W- CCS< 7000 cP @ -25C
15W- CCS < 7000 cP @ -20C
20W- CCS < 9500 cP @ -15C
There are also MRV Cold Pumping Viscosity (MRV=Mini-Rotorary Viscometer) specs and minimum viscosities involved in the J300 specs, but it all comes down to how cold pumping specs for the oil. By choosing the lowest "W" number, you can improve the cold flow of the oil as well as the "cool" flow... the first start on a 60-70 degree day for example.
Also, I have run 15w40 in my truck on occasion and when I did I checked the warm (180F) oil pressure vs 10W30 and there was only a 5 psi difference at 2000 rpm.
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CDX825
filtration nut
Great info Jim!
I will add that 5W40 being synthetic will also hold up to the heat better compared to 15W40.
I will add that 5W40 being synthetic will also hold up to the heat better compared to 15W40.
gdhillon
Full Access Member
Very informative, thanks Jim!
5W 40 = 5 Winter 40 Weight.this means instant easy flow with fast oil pressure with cold oil.as the oil temp raises to normal op temp,the oil is 40 weight.
yes its good year round.
i run Mobil 1 5w40 9k intervals.
yes its good year round.
i run Mobil 1 5w40 9k intervals.
Nice write up, but according to the oil chartlet, 5W-30 is good for below 60*F. I added F to your Centipoise ranges for us Americans.
CDX825 suggests 5W-40, however, I've never seen it in Socal, plus the chartlet doesn't list it(not that it can't be used). 5W-30 wouldn't be recommended in Socal for most of the year, but if I found 5W-40, would that increase the outside temps range enough to use in Socal? I quick searched for 5W-40, but wasn't too successful... I'm in a hurry to pick up kids, but liked the posts and felt a need to clarify.... sorry for being a slouch.
Since most of the synthetics off the shelf around here sells 5W-30.... not recommended for our average temps... what would be the next best thing in synthetics?
I get the "engine temps" argument, but... if this was 100%, then why wouldn't SAE increase the temp operating parameters for outside air temp in their chartlet? Or why wouldn't Ford make it the recommended alternative?
The coldest we've ever had at the house is +19*F.... cold as heck for us Socalerz.
Using this as data in my winter guide, I could technically use 20W-30 using the argument of outside temp minimums and outside temp maximums to determine my oil grade. That said, I'm a big fat hairy chicken and would never use it in anything I drive.... I'm more likely to follow the herd on oil grades.
Not to mention that Ford's SAE chartlet doesn't list it, much less recommend it.That said....based on the chartlet, 15W is to be used "down to" -4*F on the cold end.... so flow down to -4*F is good...IE: Not to heavy on cold starts. Whether 30 or 40 grade is used on the upper end doesn't really matter much, except that the 30 weight is probably better for lower temps outside than 40 is, however, 40 doesn't matter either because it should be the same viscosity as 30wt at the same temp, just having higher protection properties at higher than normal temps. Notice too that there is no 15W-30 listed-obviously operating range of a 30wt is too narrow on a 15W... but not on a 10W or 5W.
How's that for layman's thesis?!
I typically use 15W-40 dino. Although I think I just experienced the complaint on Rotella products disappearing in my 7.3.... nooo leaks, I'm going to Delo 15W-40 until I can figure out the proper synthetic to use for Socal. I too would use 15W-30 most everywhere, but for the heat we get in the summer freeway stagnation, I feel the 40wt is better able to handle the outside temps increasing normal engine temps better.
gdhillon
Full Access Member
^ but those are just ratings for dino?...not to sure if synthetic makes that much of a difference but from what ive read it does
After reading this link posted by OLDBULL a few months ago, I'm not using Rotella or Delo LE again. Never used Amsoil, but after seeing that report, I certainly don't think I will in the future.
Heath
Heath
PwrSmoke
Full Access Member
Heath: I'm not sure you can draw too many useful conclusions about brands from that because all the "good" oils are CI-4 and the "bad" are CJ-4 and many of the brands are represented in both categories. Also, it's a dated argument that came out in the heat of the '06 intro of ULSD and the CJ-4 oil. There wasn't much of a track record then and there was a lot of "fantasy football" prediction kinda stuff going on. Overall, CJ-4 has proven itself a pretty good oil spec for most applications. I disagree with the whole CI-4 vs CJ-4 premise, thinking it's more a case of "different" and meeting other specs than "bad" or "good." With regards to our engines... remember, they were designed for "stone-age" lubricants and held up well using them. Even the supposed "bad" CJ-4s are about 500 times better than the oils these engines were spec'ed for (how much better is SM/CJ-4 than the old CC/CD spec our engines were rated for?). I've been using CJ-4 oils in all my diesel equipment, all of it old and rated for CC, CD or CF diesel oil, and they all turn in great oil analysis with it, even with extended drain intervals.
One important thing to remember with regards to CI-4 vs CJ-4 is LSD vs ULSD. CJ-4 isn't good with high sulphur fuels... it doesn't have the additive package to cope with them. This makes it important that you match the oil to the fuel. If you are still in an area that has LSD (are there any? ... we haven't had it since '07... even off-highway farm fuel), then you NEED CI-4. Otherwise, CJ-4 is great with ULSD, easy to find and inexpensive. It's harder and harder to find CI-4 oils, or at reasonable prices. While CI-4 canbe used with ULSD just fine, I'm not sure there are any tangible benefits that warrant the extra aggro of procuring them. They are certainly "fine" but you aren't gong to find them on sale off the shelf at WalMart or the auto parts store.
Overall, I think you can easily reach a point with older diesels like ours where you are "throwing pearls to swine." What I mean is that you are putting oil in them that's so much better than they can use that you are at the point of wasting money... i.e. not getting a useful return on investment. I suppose we can argue where that return-on-investment point might be, but I think you can do quite well on a $3-4/quart oil in a 6.9/7.3L. Outside of a built, extreme Hi-Po engine, do we really "need" a $10/quart oil? Especially in a tired engine being run on a budget.
CaptTom: Remember the "chartlet" is from 1986. 5W40 didn't exist then. 5W30 was new and ****-bang. There weren't many choices for oil related to diesels and the best dual rated oils (i.e. for gas and diesel engines) combined SF/SD API specs. Even 15W40 was relatively new in 1986. Now we are up to SN/CJ-4 and you can buy 0W40 rated diesel oil. Plus, you are looking at the minimum temps in the wrong way, I think. Sure the MINIMUM spec for 15W oil is +10 and what that means is that the oil is somewhat above the "honey" viscosity stage at that temp. It's not optimal there. Like I said, in a warm weather climate, a 15W40 isn't the downer it might be in cooler weather, especially considering that wonderful oil-to-water cooler our engines have that gets oil temp up quickly. BUT, a better W number also ensures better flow at those inbetween temps.... a 60F morning for example. Synthetic base oil, whether Group III or IV or V, are the flow masters and that's where you will find the best oil flow at any temp... hence the 5W40 (in the Rotella its a Group III base oil). I like the lightest oil that's safe because it avoids oil filter bypass and unfiltered oil. I'll take slightly increased FE as a side bennie.
Oil consumption? I've CURED oil consumption problems in engines using Rotella oils and in 25 years of owning my truck, it's always used a quart every 1500 miles or so from new. More when the valve stem seals get worn. Doesn't matter which brand oil is in it. My point is that it's not a case of "engines use more oil using Rotella vs other oils," though it may be a case that some do and some don't on an individual basis. Not universal. Rotella's NOACK and flashpoint specs are among the best in their price ranges and that's one indicator in the specs that relates to potential oil use. Viscosity can change oil consumption, but it's not always a case of heavier=less consumption. Sometimes a lighter oil will help an engine use LESS oil.
One important thing to remember with regards to CI-4 vs CJ-4 is LSD vs ULSD. CJ-4 isn't good with high sulphur fuels... it doesn't have the additive package to cope with them. This makes it important that you match the oil to the fuel. If you are still in an area that has LSD (are there any? ... we haven't had it since '07... even off-highway farm fuel), then you NEED CI-4. Otherwise, CJ-4 is great with ULSD, easy to find and inexpensive. It's harder and harder to find CI-4 oils, or at reasonable prices. While CI-4 canbe used with ULSD just fine, I'm not sure there are any tangible benefits that warrant the extra aggro of procuring them. They are certainly "fine" but you aren't gong to find them on sale off the shelf at WalMart or the auto parts store.
Overall, I think you can easily reach a point with older diesels like ours where you are "throwing pearls to swine." What I mean is that you are putting oil in them that's so much better than they can use that you are at the point of wasting money... i.e. not getting a useful return on investment. I suppose we can argue where that return-on-investment point might be, but I think you can do quite well on a $3-4/quart oil in a 6.9/7.3L. Outside of a built, extreme Hi-Po engine, do we really "need" a $10/quart oil? Especially in a tired engine being run on a budget.
CaptTom: Remember the "chartlet" is from 1986. 5W40 didn't exist then. 5W30 was new and ****-bang. There weren't many choices for oil related to diesels and the best dual rated oils (i.e. for gas and diesel engines) combined SF/SD API specs. Even 15W40 was relatively new in 1986. Now we are up to SN/CJ-4 and you can buy 0W40 rated diesel oil. Plus, you are looking at the minimum temps in the wrong way, I think. Sure the MINIMUM spec for 15W oil is +10 and what that means is that the oil is somewhat above the "honey" viscosity stage at that temp. It's not optimal there. Like I said, in a warm weather climate, a 15W40 isn't the downer it might be in cooler weather, especially considering that wonderful oil-to-water cooler our engines have that gets oil temp up quickly. BUT, a better W number also ensures better flow at those inbetween temps.... a 60F morning for example. Synthetic base oil, whether Group III or IV or V, are the flow masters and that's where you will find the best oil flow at any temp... hence the 5W40 (in the Rotella its a Group III base oil). I like the lightest oil that's safe because it avoids oil filter bypass and unfiltered oil. I'll take slightly increased FE as a side bennie.
Oil consumption? I've CURED oil consumption problems in engines using Rotella oils and in 25 years of owning my truck, it's always used a quart every 1500 miles or so from new. More when the valve stem seals get worn. Doesn't matter which brand oil is in it. My point is that it's not a case of "engines use more oil using Rotella vs other oils," though it may be a case that some do and some don't on an individual basis. Not universal. Rotella's NOACK and flashpoint specs are among the best in their price ranges and that's one indicator in the specs that relates to potential oil use. Viscosity can change oil consumption, but it's not always a case of heavier=less consumption. Sometimes a lighter oil will help an engine use LESS oil.
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After spending time going over UOA's on BITOG, I've come to agree with pwrsmoke. I run whats cheap and on sale. Plenty of good reports running cj-4 oils with rediculous drain intervals.
Not to mention the formulations change on such a regular basis, you can never tell what your getting. Reports from 5 years ago are useless, as the formulations probly changed 5 times already. If your changing your oil with a modest drain interval, any diesel spec oil will be more than fine...
Not to mention the formulations change on such a regular basis, you can never tell what your getting. Reports from 5 years ago are useless, as the formulations probly changed 5 times already. If your changing your oil with a modest drain interval, any diesel spec oil will be more than fine...
!! BITOG rejected my membership, don't know why. I asked em why and no response.
In regards to Rotella, I've used it exclusively in my 6.0. I like the anti-corrosion properties of it. Never had a dilemma using it either. I did my second oil change on the 7.3 with Rotella (first one was Delo) and somehow I ran low very quickly. And no, it wasn't a bad change, I not only have the empties, but I always do a warm up afterwards and recheck oil levels for the last top off. I too was doubtful of the Rotella claims until it happened to me. Unfortunately, I didn't record mileage at time of change out, so can't tell how much/mile it used.
If it happens again with Delo, I will have to look elsewhere. Yes, I rechecked filter seat and drain plug, no drips or leaks from either, running or sitting off.
Appreciate all the responses, but still no good answers to what would be best synthetics to run in warmer climates. It seems to me the 5W's are just a bit too low for my nerves to try.
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