Alright, someone please tell me this is about normal? I switched to Amsoil on my last oil change. I'm now about 4300 miles into it, and I checked the oil level recently before I went down to see my parents for christmas. Its a good thing I checked! The level was below the add mark and I had 2 quarts left of this liquid gold to add back into the safe area. I noticed the oil pressure gauge showed a little bit longer of a delay in building pressure on initial startup and pressure was a little lower than normal. Nothing that raised a red flag, but now I know why it was so.

 

I have noticed since the change that the blowby vapor looks as though it has increased and there is some more oil "condensating" on the differential from the breather. As well, using more than 2 quarts up in approximately 4300 miles.

 

Is this a sign of a failing engine?

 

I was running DELO 400LE before the switch and maybe added a quart or so during the life of an oil change(7500 miles).

 

..believe you me, I can't pull my 5th wheel with a couple mules!

Thing is I don't see (personally) any reason for synthetic oils in these trucks. When there is members like CajFlynn putting over million miles on a truck on dino oil. Then flip the page and watch Dorkweed run 84k miles on a single oil change with WalMart oil. (Blackstone tested every 7k miles). So with these two members you can learn a lot...

The only reason I really switched to the synthetic was because the dino oil wouldn't flow in -60 degree weather up in North Dakota. It would literally take more than 5 minutes to build 40 psi on my mechanical gauge. I think I will be switching back to dino oil now that I live in Missoula and wont have to deal with much under 0 for the most part.

I've been using 15-40 ams oil with single bypass filter for two years now, takes exactly 12 qts to top of fill mark. I put about 4-5 k on it a year and it always stays at the top. Also noticed that it stays cleaner a lot longer, it may be because of 2 micron bypass. Did my oil test at CAT and the only thing was way high is soot, 60 or so. but it said keep using it and sample at regular intervals, whatever they are. I just did it for the hell of it. Changed it anyway it was 14 months old. But I wonder why you have to change oil every so many miles or every year which ever comes first, what if I don't put many miles on it in a year what goes bad? Oil in a bottles don't go bad on a shelf and if an oil test comes back good then why change it every year?

Oil will pick up condensation, especially short trips stop and start. Synthetic is for those that run at least 15,000 per year. Leaking? I had a differential repair shop back In the day of leather axle seals. Amsoil would disappear in a flash. I fully advised against it back then. A great semi-synthetic that will run 4 times delo 400 is Schaffer. Reasonable price for a synthetic. Lots of fleets use it.