Mobil Delvac 15w40

[Garak]

Originally Posted By: dnewton3
You're in LA and worried about cold starts? That's plain silly. Your environment simply is not anywhere near extreme enough to warrant synthetics in regard to cold start cranking and flow.


If I were in LA, my Audi would see Delvac 1300 15w-40 year round. It's the recommended viscosity for the lowest temperature LA would ever see. Cold starts in LA. That's a good one.

 

[Gokhan]

The engine and current oil I have is listed in my signature lines.

My impression of the Mobil Delvac 1300 Super 15W-40, which I used for several years, was that the oil consumption would be very little for the first 1,000 miles and then it would increase to about 1 qt per 1,000 mile.

It's absolutely true that cold starts in LA, where the night temperatures in the winter are no less than about 40 - 45 F, are only a secondary thought; although, I still prefer to have as little viscosity as possible for cold starts to prolong engine life.

The other problem with the 15W-40 was that the engine ran rougher than with the 5W-30.

As I said I am experiencing with the PP 5W-30 now. The consumption seems to have gone over 1 qt per 1,000 miles from the start and it's been about 800 miles now. I will wait and see what happens after 2k or 3k miles. But engine runs smoother with PP and fuel economy (in the upper 20s) is about 8% better than with 15W-40. This is probably due to oil being synthetic and lower viscosity and perhaps PP's claims about engine cleaning are true as well. More friction modifiers in PP and gasoline-engine-tailored additive package probably helps for smooth engine performance as well.

 

[dnewton3]

I might suggest you do a compression check on your engine. That will help diagnose the area of possible oil consumption. If the rings are the culprit, I have a suggestion to try some ARX for one or two cleaning cycles. You might just have sticking rings, and the oil cannot compensate for that forever.

Also, if you have internal seals (valve stems) that are hardening due to combustion byproducts, ARX will clean them and allow them to be pliable again. If the seals have true wear degredation, the ARX cannot restore the damage.

If the oil consumption is a true loss due to worn seals such as at the crank, where the oil actually escapes rather than being consumed, you'd know it by oil dripping everywhere.

ARX is a cleaning agent; it liberates the seals, rings, etc to do their job as if they were new. It is not capable of mechanically reproducing seal or ring material if there is physical damage, nor will it form a barrier. That's the difference. I personally had fantastic results regarding sticking rings in my Taurus, and the ARX completely restored my compression over two clean/rinse cycles. One cylinder in particular came up from 110 psi to 180 psi!

 

[Gokhan]

Thanks for the tips. I may borrow a compression gauge and test it during the next tune-up I will perform in the fall. I will give the Auto-Rx a thought.

My engine has very good power and fuel economy. It also passes the strict California dyno emission tests performed at 15 MPH and 25 MPH. If the oil consumption stays below 1 qt/kmile, I could live with it. I don't have a private garage to rebuild the engine and I don't like other people working on my car.

Note that Pennzoil Platinum also advertises itself as the best engine-cleaning oil in the market. I have used it for about 900 miles now. I don't know how much problem I have with dirty engine parts but it always helps to have the engine clean. Certainly I would also have more peace of mind with Pennzoil Platinum than with an oil treatment like Auto-Rx.

I will update on the oil consumption after a few kmiles. It's well known for thinner grades to increase the oil consumption and I might have to try Rotella T6 full synthetic 5W-40 if it's excessive. It's selling for $19.50 per gallon at Wal-Mart. I would hate to switch back to a diesel-engine/HDEO oil though because my engine is running so well with the GF-5 oil.

 

[Gokhan]

Question: Which oil performs best in UOA -- Rotella T6 5W-40, Mobil 1 Turbo Truck 5W-40, Mobil Delvac 1300 Super 15W-40, Valvoline Extreme 5W-40, or some other oil, especially regarding viscosity retention and TBN retention? Anyone knows?

This question is in case I have to switch back to xW-40 grade. Another option would be the Mobil 1 High Mileage 10W-40 but I am worried about seal conditioners harming the seals.

 

[dnewton3]

There is no "best" oil. If you haven't discovered that by now, you soon will.

There are plenty of good quality oils that will all perform well.

You need to define many things before you can really decide which oil is optimum for you application. PM plan, OCI interval, environment, cost, etc all play into this.

If you REALLY want to know which is "best" for your unique situation, you'll have to do many UOAs by brand and grade, running several per brand/grade over many OCIs, and then compare/contrast the results. Depending upon how many miles you drive per year, it could take years to really get true results about which is "best".

But all will perform well enough.

 

[Gokhan]

Well, my user manual recommends all fuel-efficient S or S/C multigrades between 5W-30 and 20W-50 (though restricting 5W-30 to cold and only cold temperatures). If the oil consumption turns out to be a problem, I will switch back to the glorious Mobil Delvac 1300 Super 15W-40, which was miraculously the only 15W-40 that was certified for the ultimately demanding CF-2 category until API discontinued the CF and CF-2 categories for good recently.

The main drawback of going back to Mobil Delvac 1300 Super 15W-40 would be an 8% drop in fuel economy, but then I would have the peace of mind of knowing that I am not getting any engine wear even when I am going full throttle 10% uphill grade in Nevada mountains at 75 MPH in 120 F weather, while passing BMWs along the way.

 

[dnewton3]

Originally Posted By: Gokhan
... but then I would have the peace of mind of knowing that I am not getting any engine wear even when I am going full throttle 10% uphill grade in Nevada mountains at 75 MPH in 120 F weather, while passing BMWs along the way.

Show no mercy! Flog that little thing to within an inch of it's life!

 

[hedgehorn]

Originally Posted By: Gokhan
Well, my user manual recommends all fuel-efficient S or S/C multigrades between 5W-30 and 20W-50 (though restricting 5W-30 to cold and only cold temperatures). If the oil consumption turns out to be a problem, I will switch back to the glorious Mobil Delvac 1300 Super 15W-40, which was miraculously the only 15W-40 that was certified for the ultimately demanding CF-2 category until API discontinued the CF and CF-2 categories for good recently.

The main drawback of going back to Mobil Delvac 1300 Super 15W-40 would be an 8% drop in fuel economy, but then I would have the peace of mind of knowing that I am not getting any engine wear even when I am going full throttle 10% uphill grade in Nevada mountains at 75 MPH in 120 F weather, while passing BMWs along the way.

8% drop in fuel economy?

 

[Gokhan]

Originally Posted By: hedgehorn
Originally Posted By: Gokhan
Well, my user manual recommends all fuel-efficient S or S/C multigrades between 5W-30 and 20W-50 (though restricting 5W-30 to cold and only cold temperatures). If the oil consumption turns out to be a problem, I will switch back to the glorious Mobil Delvac 1300 Super 15W-40, which was miraculously the only 15W-40 that was certified for the ultimately demanding CF-2 category until API discontinued the CF and CF-2 categories for good recently.

The main drawback of going back to Mobil Delvac 1300 Super 15W-40 would be an 8% drop in fuel economy, but then I would have the peace of mind of knowing that I am not getting any engine wear even when I am going full throttle 10% uphill grade in Nevada mountains at 75 MPH in 120 F weather, while passing BMWs along the way.

8% drop in fuel economy?

Yes, compared to CJ-4/SM 15W-40, GF-5/SN/Resource Conserving 5W-30 resulted in about a 7% (2 MPG) increase in fuel economy under my driving experience (correcting 8% to 7% after checking my numbers).

 

[Gokhan]

Originally Posted By: dnewton3
Flog that little thing to within an inch of it's life!

It's a nice classic subcompact.

More pics

Pennzoil Platinum Full Synthetic GF-5/SN/Resource Conserving 5W-30 resulted in excessive oil consumption. I am back to Mobil Delvac 1300 Super 15W-40! GF-5 oils probably don't have enough ZDDP for my flat-tappet valve train either. So, I should benefit from the generous amount of ZDDP in Mobil Delvac 1300 Super 15W-40, in addition to the high viscosity and excellent HTHS. It's the million-mile oil and I only have about 231,000 miles after all.

 

[Garak]

Originally Posted By: Gokhan
I am back to Mobil Delvac 1300 Super 15W-40! GF-5 oils probably don't have enough ZDDP for my flat-tappet valve train either. So, I should benefit from the generous amount of ZDDP in Mobil Delvac 1300 Super 15W-40, in addition to the high viscosity and excellent HTHS.


As you're already aware, I have no hesitations about using dual rated HDEOs in gasoline engines. However, it might be worthwhile to point out that I've been led to believe that OHC engines (I'm assuming that's what's in your car) don't have the valve spring pressures to require extra ZDDP. Perhaps others can assist us in this matter.

In any case, it's not much of an issue for you either way, since Delvac 1300 will suit you well year round. You're not going to be hitting -40 there, unlike up here.

 

[Gokhan]

Originally Posted By: Garak
Originally Posted By: Gokhan
I am back to Mobil Delvac 1300 Super 15W-40! GF-5 oils probably don't have enough ZDDP for my flat-tappet valve train either. So, I should benefit from the generous amount of ZDDP in Mobil Delvac 1300 Super 15W-40, in addition to the high viscosity and excellent HTHS.


As you're already aware, I have no hesitations about using dual rated HDEOs in gasoline engines. However, it might be worthwhile to point out that I've been led to believe that OHC engines (I'm assuming that's what's in your car) don't have the valve spring pressures to require extra ZDDP. Perhaps others can assist us in this matter.

In any case, it's not much of an issue for you either way, since Delvac 1300 will suit you well year round. You're not going to be hitting -40 there, unlike up here.

It's a 74 HP 1.6 L SOHC flat-tappet-valvetrain engine with a lean-burning dual-barrel carburetor (the "L" in 4A-LC) and dozens of emission-control systems (the "C" in 4A-LC).

The owner's manual specifies all SF or SF/CC grades between 10W-30 and 20W-50 and 5W-30 for only temperatures below -10 F and not above 50 F. 15W-40 or 20W-50 is specified OK for above 10 F. In LA the lowest you could have is around freezing.

Since it's an older engine design, it also has somewhat higher clearances, benefiting from higher viscosity to control engine wear and oil consumption. Higher viscosity also helps control leaks around worn seal. Higher ZDDP is also a plus to reduce engine wear. The moly in Delvac also enhances the effectiveness of ZDDP, and synthetic oils tend not to have moly, which is bad for engine-wear control. So, you get the benefits of conventional oil with great solvency and seal compatibility and the presence of moly. I change the oil every 3 months; so, the shorter OCI with conventional oils is not a concern. The excellent HTHS of Mobil Delvac 1300 Super 15W-40 is also great for hot days of the Southwest. Therefore, I certainly have the peace of mind with Mobil Delvac 1300 Super 15W-40, and I will stick with it from now on.

 

[CourierDriver]

Originally Posted By: Gokhan
Originally Posted By: Garak
Originally Posted By: Gokhan
I am back to Mobil Delvac 1300 Super 15W-40! GF-5 oils probably don't have enough ZDDP for my flat-tappet valve train either. So, I should benefit from the generous amount of ZDDP in Mobil Delvac 1300 Super 15W-40, in addition to the high viscosity and excellent HTHS.


As you're already aware, I have no hesitations about using dual rated HDEOs in gasoline engines. However, it might be worthwhile to point out that I've been led to believe that OHC engines (I'm assuming that's what's in your car) don't have the valve spring pressures to require extra ZDDP. Perhaps others can assist us in this matter.

In any case, it's not much of an issue for you either way, since Delvac 1300 will suit you well year round. You're not going to be hitting -40 there, unlike up here.

It's a 74 HP 1.6 L SOHC flat-tappet-valvetrain engine with a lean-burning dual-barrel carburetor (the "L" in 4A-LC) and dozens of emission-control systems (the "C" in 4A-LC).

The owner's manual specifies all SF or SF/CC grades between 10W-30 and 20W-50 and 5W-30 for only temperatures below -10 F and not above 50 F. 15W-40 or 20W-50 is specified OK for above 10 F. In LA the lowest you could have is around freezing.

Since it's an older engine design, it also has somewhat higher clearances, benefiting from higher viscosity to control engine wear and oil consumption. Higher viscosity also helps control leaks around worn seal. Higher ZDDP is also a plus to reduce engine wear. The moly in Delvac also enhances the effectiveness of ZDDP, and synthetic oils tend not to have moly, which is bad for engine-wear control. So, you get the benefits of conventional oil with great solvency and seal compatibility and the presence of moly. I change the oil every 3 months; so, the shorter OCI with conventional oils is not a concern. The excellent HTHS of Mobil Delvac 1300 Super 15W-40 is also great for hot days of the Southwest. Therefore, I certainly have the peace of mind with Mobil Delvac 1300 Super 15W-40, and I will stick with it from now on.



Just use rotella t6 5w40 and have a nice day.

 

[Gokhan]

Originally Posted By: CourierDriver
Originally Posted By: Gokhan
Originally Posted By: Garak
Originally Posted By: Gokhan
I am back to Mobil Delvac 1300 Super 15W-40! GF-5 oils probably don't have enough ZDDP for my flat-tappet valve train either. So, I should benefit from the generous amount of ZDDP in Mobil Delvac 1300 Super 15W-40, in addition to the high viscosity and excellent HTHS.


As you're already aware, I have no hesitations about using dual rated HDEOs in gasoline engines. However, it might be worthwhile to point out that I've been led to believe that OHC engines (I'm assuming that's what's in your car) don't have the valve spring pressures to require extra ZDDP. Perhaps others can assist us in this matter.

In any case, it's not much of an issue for you either way, since Delvac 1300 will suit you well year round. You're not going to be hitting -40 there, unlike up here.

It's a 74 HP 1.6 L SOHC flat-tappet-valvetrain engine with a lean-burning dual-barrel carburetor (the "L" in 4A-LC) and dozens of emission-control systems (the "C" in 4A-LC).

The owner's manual specifies all SF or SF/CC grades between 10W-30 and 20W-50 and 5W-30 for only temperatures below -10 F and not above 50 F. 15W-40 or 20W-50 is specified OK for above 10 F. In LA the lowest you could have is around freezing.

Since it's an older engine design, it also has somewhat higher clearances, benefiting from higher viscosity to control engine wear and oil consumption. Higher viscosity also helps control leaks around worn seal. Higher ZDDP is also a plus to reduce engine wear. The moly in Delvac also enhances the effectiveness of ZDDP, and synthetic oils tend not to have moly, which is bad for engine-wear control. So, you get the benefits of conventional oil with great solvency and seal compatibility and the presence of moly. I change the oil every 3 months; so, the shorter OCI with conventional oils is not a concern. The excellent HTHS of Mobil Delvac 1300 Super 15W-40 is also great for hot days of the Southwest. Therefore, I certainly have the peace of mind with Mobil Delvac 1300 Super 15W-40, and I will stick with it from now on.



Just use rotella t6 5w40 and have a nice day.

I've looked at Rotella T6 Full Synthetic 5W-40 very carefully as well but Delvac 15W-40 has far better HTHS (4.3 vs. 3.8) and better 100 C viscosity as well (15.0 vs. 14.2), and that's why I wanted to stick with it. But if I lived in a cold climate, I would have to use a synthetic 5W-40 oil. Synthetics also tend not to have moly, which can potentially increase engine wear by reducing the effectiveness of ZDDP. Since I change my oil every 3 months, there seems to be no reason to pay 2x $$ for synthetic oil. Also, with conventional oil, I don't have to worry about my seals deteriorating more rapidly.

 

[Garak]

Originally Posted By: Gokhan

It's a 74 HP 1.6 L SOHC flat-tappet-valvetrain engine with a lean-burning dual-barrel carburetor (the "L" in 4A-LC) and dozens of emission-control systems (the "C" in 4A-LC).

The owner's manual specifies all SF or SF/CC grades between 10W-30 and 20W-50 and 5W-30 for only temperatures below -10 F and not above 50 F. 15W-40 or 20W-50 is specified OK for above 10 F. In LA the lowest you could have is around freezing.

Since it's an older engine design, it also has somewhat higher clearances, benefiting from higher viscosity to control engine wear and oil consumption. Higher viscosity also helps control leaks around worn seal. Higher ZDDP is also a plus to reduce engine wear. The moly in Delvac also enhances the effectiveness of ZDDP, and synthetic oils tend not to have moly, which is bad for engine-wear control. So, you get the benefits of conventional oil with great solvency and seal compatibility and the presence of moly. I change the oil every 3 months; so, the shorter OCI with conventional oils is not a concern. The excellent HTHS of Mobil Delvac 1300 Super 15W-40 is also great for hot days of the Southwest. Therefore, I certainly have the peace of mind with Mobil Delvac 1300 Super 15W-40, and I will stick with it from now on.


Makes sense to me. The suggestion you received about using the Rotella synthetic is not a bad one. Considering it's a Group III/III+ synthetic, at least to my knowledge, I don't think it would cause you any seal issues. However, given your maintenance plan and and year round ambient temperatures, Delvac 1300 will suit you well and at a good price point. You should be able to get it in a 5 gallon pail, which is how I prefer to get Delvac 1300.

Up here, because of the cold, I plan to get Esso XD-3 HDEO (Imperial Oil is our version of ExxonMobil) in 5w-30 for my old F-150 next winter. It's conventional and is basically the same line as Delvac 1300; from what I understand, XD-3 15w-40 HDEO is being discontinued with Delvac 1300 taking its place, presumably to avoid overlap.

I was very pleased with Delvac 1300 in my Audi. It's the recommended summer grade. For my F-150, I used that regularly in the summer, also with good results. It cleaned up that sludge very nicely prior to the rebuild.

I'm considering trying synthetic Delo 400 LE 5w-40 year round in both vehicles. That's only because I can get in in five gallon pails at a very low price. I would prefer, however, to remain with the Delvac 1300, since it's cheaper still and definitely does the job.

Don't get me started about some of those mid 1980s emissions carbs. The carb in the F-150 was a major reason behind so much of the trouble with that vehicle. With the rebuild, the carb took a nice trip to the landfill.

 

[Gokhan]

Originally Posted By: Garak
Don't get me started about some of those mid 1980s emissions carbs. The carb in the F-150 was a major reason behind so much of the trouble with that vehicle. With the rebuild, the carb took a nice trip to the landfill.

Yes, the emission-control systems on the mid-80s carbureted cars are extremely complicated and very few mechanics nowadays know about them. That's the most common place of failure for these cars. Also, when one emission-control system fails, it could lead to a chain reaction of breakdowns. Likewise, if some mechanic crosses two of the three dozen vacuum hoses or improperly adjusts or repairs an emission-control system, it could lead to a chain reaction of engine problems.

On my car I have become an expert on the emission-control systems. Currently they are all OK. I also did a complete rebuild of the carburetor myself with genuine parts. At one point I was almost going to get rid of the car because of serious cold-engine problems. Eventually I discovered it to be because of a faulty thermostatic vacuum-switching valve (TVSV), which was opening the choke when the engine was cold. Carburetor was mostly fine, except for a mysteriously bent float (bad mechanic messing with it or factory defect) but I rebuilt it because I couldn't figure out what was wrong with the car until I discovered the TVSV problem. The other problems were an EGR vacuum-modulator valve with a torn diaphragm (apparently a common problem) and an EGR valve completely clogged with hard carbon deposits (which I was able to fully clean with a hard wire and brake-cleaner solvent). Also, the ring-shaped air filters on these cars can easily be improperly or poorly seated and sealed and leak dust into the engine or the hot-idle-compensation (HIC) valve; so, you need to use a genuine air filter and be very careful when you replace it. Anyway, right now, all my fuel, emission, and electrical systems are in 100%-healthy condition. There are small leaks in the manifold gasket, some oil seal(s), and some valve guide(s), but I am not going to do a complete engine rebuild.

 

[Gokhan]

Originally Posted By: Garak
Makes sense to me. The suggestion you received about using the Rotella synthetic is not a bad one. Considering it's a Group III/III+ synthetic, at least to my knowledge, I don't think it would cause you any seal issues. However, given your maintenance plan and and year round ambient temperatures, Delvac 1300 will suit you well and at a good price point. You should be able to get it in a 5 gallon pail, which is how I prefer to get Delvac 1300.

Yes, the temperature here is hardly ever below freezing and I follow no longer than a 5,000-mile or 6-month OCI, and synthetic oil would probably have no benefits for me. I also like the higher 100 C and HTHS viscosity of Delvac 1300 Super 15W-40. It also has moly, which greatly increases the efficiency of ZDDP, and Rotella T6 doesn't have it I believe. Another thing I dislike about synthetic oils is the foul odor, caused by the inherent odor of the synthetic base stocks as well as the poor burning ability of the synthetic base stocks, which is more of a problem in older cars.

Here it's sold in a gallon container and it's $9.88 at Wal-Mart. Rotella T6 is $19.88 I believe. I will post pics of the container when I get a chance. The only downside of it for me with respect to GF-5 oils seems to be a 7% (2 MPG) drop in fuel economy, but I can hardly care. Engine longevity and lower oil consumption are more important.

 

[Garak]

Originally Posted By: Gokhan
Here it's sold in a gallon container and it's $9.88 at Wal-Mart. Rotella T6 is $19.88 I believe. I will post pics of the container when I get a chance. The only downside of it for me with respect to GF-5 oils seems to be a 7% (2 MPG) drop in fuel economy, but I can hardly care. Engine longevity and lower oil consumption are more important.


That's certainly a good price. I can't get it for that up here, certainly. The only thing I can get for such prices is the occasional PCMO on rollback. That being said, as I've addressed before, one can drive oneself nuts trying to find every rollback and ruminating over one overpaid when it drops another dollar the next week.

For the carbs and emissions systems, it's good that you know yours and found at least most of what you needed. For the F-150, it simply wasn't cost effective. Tracking down all the parts in Canada would have been a chore, and to get an OEM carb was around $900, which is ridiculous. It needed a rebuild and a functioning carb far more than it needed an OEM carb for the extra cost.

 

[Gokhan]

Here is the picture of the Mobil Delvac 1300 Super 15W-40 1 US gallon container I bought for $9.87 + tax (9.75%) at Wal-Mart:

This oil has been working very well with my engine. I have been using it for the last four years or so. It also decreases the oil consumption substantially in comparison to xW-30 oils. Most importantly it provides virtually unbeatable wear protection. It's great oil if the viscosity is recommended for your engine.