Full synthetic oil question.

[codgerbill]

I had full synthetic oil put in the engine when the spring maintenance was done. I think it was 5W30. On the last trip I got a "check engine oil level" light. I pulled into a shopping center and checked the oil level and the level was below the mark on the dipstick. I went to an auto parts store and bought 2 quarts of full synthetic oil (5W30) and added 1 quart. The level was ok on the dipstick and the light ("check engine oil level") did go out. I was on my way to an outing with a Winnebago group and I mentioned that I had the "check engine oil level" light come on and thought it was unusual because when I used Dino oil in my former coach (Ford V10) I never had that problem. One of the guys I was talking to mentioned that he had the same problem (talking about full synthetic oil) and simply switched to (if I correctly remember) 10W-30 and that caused the problem to go away. The only downside (so he said) would be that it might be a little harder starting in the colder weather. Is there that much of a difference in the oil viscosities that would cause me to have the "check engine oil level" and should I be concerned?

[wildtoad]

What does the engine manual say to use in your engine?

[OSP1268]

For what it is worth. I have always heard that you don't want to change to synthetic oil on an older engine. The reason being that it will loosen sludge up and if the engine has any leaks it will be worse with the synthetic because it flows better.

[ga traveler]

The Ford manual says it is OK to use 10W30 above 32 deg. I drive a 99 Pace Arrow. I changed to 5W30 syn. when we started to go out west in 2007. I have had no problem with usuage. I went to 10W30 in 2009, after checking with Ford. I thought it might give a little more protection in the heat out west.

[az bound]

If the engine is a GM 8.1L it is not all that unusual for it to use 1 qt. of oil for every 100 gal. of gass burned. The oil viscosity may cause this to vary, I run 10w40 and average 1qt. every 1500 miles or 200 gal.

[codgerbill]

I dunno. If I have the manual it would be on the coach (back in storage lot now). The shop where I have all my work done, did the spring service for me. That service included engine oil & filter, chasis lube, transmission & cooling system flush and generator service. The owner has a motorhome and they work on all kinds of vehicles (Gas & diesel) so I am confident that they know what they are doing. I am assuming the 5W30 is a oil that protects better in the hotter weather (but whadda I know).

[FrankO]

Did you check to see if they had filled to the top mark on the dip stick? When the filter and oil are changed there is an odd amount of oil that has to be used to fill to the top mark depending on the size of the filter you use. They may have rounded it off and been a little shy. Just a thought
Frank O.

[wa8yxm]

A lot of the myths about Full Synthetic oils come from one company which changed it's formula sometime last century.

The original formula had something in it that did major damage inside older engines and did not mix well with Dino Oil.. As I said, they changed that formula and quick.

Today you have basically one or two full synthetic oils out there, and I'm not sure about either of them.. Mobile 1 and Amisoil.

The rest are really super highly refined Dino Oil. Now, that said, they are sufficently refined that they do exhibit all the lubrication properties of the Full Synthetics.

(Shell, by the way, admits this.. Just so you know)

As to using oil.... I can drive my Motor home all summer, No need to add oil

All winter, No need to add oil

However in between... I take about an 800 mile hike over some mountains.

When I come down out of the mountain,, I have to add oil

So it may be how you were driving (Note: this spring I took a genteler route and did NOT have to add as much oil) When you are putting the pedal to the metal as they say, it sometimes sucks a bit of oil in, I don't knwo if it's coming in via the valve seals or the rings, but it's only when you are working the pistions off that engine that it happens. At least on my Chevy engine.

So long as you do not need to add more than once per oil change.. I'd not worry Just check it every once in a while.

[dsbike]

To answer your original question 5w30 vs 10w30. 5w30 is a lighter viscosity when cold than 10w30, therefore at start up is easier on your engine. Switching to 10w30 on a high mileage engine would make sense due to the wear from when it was new. But I do not recommend this if you are not using oil. You said the dipstick indicated that you were down 1 qt., I have seen a few engine that will trip the light at the 1qt low mark, most are 2 or more qts low. Doesn't make any difference of the make or model. If your engine has low mileage, less than 100K, I would stay with the 5w30. I would also recommend Amsoil. I am not a dealer for them, but I do use thier oil. I have read several reports & tests on several brands of syn oil & Amsoil almost always comes out on top & in the top 2 of the best performing syn oils. I recently tore down a Jeep 4.0L engine that had a cracked block due to the waterpump coming apart & adding water to a running engine , but no circulation. This engine had 207K miles on it, it did not use any oil, 1 qt every 12K miles, I used Amsoil in it since 10K. 25K useage between oil changes or once a year. The bearings & cylinder walls showed no wear except for the one that cracked & destroyed the piston.

[Full-Timers]

From the Workhorse chassis guide.

For all temperature ranges the
preferred oil for your engine is SAE 5W-30. However,
you can use SAE 10W-30 if temperatures stay above 0
degrees F (18 degrees C). For heavy-duty driving in
summer temperatures, above 40 degrees F (4 Degrees
C), there can be an advantage to a single-viscosity
straight SAE 30.

[TrekPR]

You don't say how may miles you had on the oil change when you added the quart? Did you have to add more oil on the return trip? When I have someone change the oil I always check the stick before leaving. When I change the oil I always check the stick before leaving, everyone makes mistakes even the good shops.

[codgerbill]

I would have to guess on the mileage, but I think it was around 2500 +or-, or so.... I did buy 2 quarts of the full synthetic (added 1 quart) and will check the dipstick ocassionally too. I checked the oil level on the dipstick after arriving at the campground and again when the trip was done and the coach was at the storage lot. The level is still on the midpoint of the dipstick. With the former coach (Ford V10) I just had the auto/truck shop just change the oil at 3000+ miles but I was using dino oil then. The Workhorse I have now has about 54,000+ miles on it at this time. I guess I just assumed that the full synthetic would not need to be monitored as much as the dino oil.

[DriVer]

Quote:

Originally Posted by ga traveler The Ford manual says it is OK to use 10W30 above 32 deg.

The Workhorse manual says that you can use 10W-30 motor oil down to 0° Fahrenheit. √

[DriVer]

Quote:

Originally Posted by wa8yxm So long as you do not need to add more than once per oil change.. I'd not worry Just check it every once in a while.

Professional drivers, firefighters and or ex-military like myself have had is stamped in our minds to check the oil prior to each movement when the vehicle has sat for any time. Putting off checking oil before movement might not be such a good thing and it only takes a minute of your time to get that done. Just include it in your pre-flight as a normal thing to do and you won't think twice about it.