Maybe I made a mistake but I went and bought some of that Castrol Syntec blend and changed my oil at 10,000 (brand new first change) then I noticed my milage going down a bit when in reality it is supposed to improve. so after 5000 miles on this castrol syntec 15w 40 stuff I decided to go back to rotella. Well they talked me into going all synthetic at the store and now I am running a little better milage (19mpg to 20 mpg highway) and have three brand new gallons of rotella 5W 40 full synthetic in my truck. I also went with a Wix filter and have read all these bad things about them.. Should I yank this filter out? And what about all these changes I have made? hope that I am not hurting anything but am planning on staying with the Rotella 5w 40 Synthetic for good.

so...

Was it bad to change oil like that diffferent brands and times?

Rotella Synthetic any good, any news on it?

5W 40 verses recommeded 15W 40 any thing wrong with doing this?

wix oil filters? What should I use?

I want this to be a 500,000+ mile truck, i make sure I change my own oil every time and have the assurance that the filter is on tight.

Any advice or comments on these questions is greatly appreciated

 

I can't speak to the filter, but the oil is fine. I was on the cummins site the other night looking at the engine owners manual. It say that 5w-40 synthetic is fine, but you shouldn't extend the change interval because of syn oil. I have used the rotella version in my old truck '04 Ford 6.0, and it ran great. If there was ever an engine that is oil sensitive it is the 6.0. I have read on this site that you shouldn't switch to syn until 20k miles but can't confirm or deny that one. I figure the enigne was designed for dino juice and the syn costs so much more, and you can't extend the interval so syn is not for me, except for winter time when the 5w starts flowing faster on cold starts.

 

for the summer time the 5-40 is a bit thin. that weight oil would be better used for winter time for ease of start-up lubrication. but for the most part the 5-40 will be fine. but just remember thicker oils do better in the summer and thinner oils do better in winter. that is all depending on your area, here in GA I run 15-40 year round since it doesnt stay as cold as up north.

rotella is some good stuff, but the rotella T stuff REALY stinks. of all the dino's either mobil delo or rotella is all I would use. synthetics, rotella is good, but amsoil is better.

for filtering the wix will be ok, for piece of mine I use fleetguard filters. Fleetguard is a division of cummins, and the filter DC uses on these trrucks is only a remarked fleetguard standard filter, I get the strattapore, filters to a smaller particle.

from the reasearch I have found on these engines, around 20K is a good time to switch to synthetics. before that the rings are still seating, the rod and crank caps are wearing in as well as the lifters. synthetics are so good at lubricating they actualy inhibit this process that actualy makes the engine more efficient over time.

I wouldnt yank that filter out unless it was a fram. frams are ok for gassers, but cannot handle the oil pressures of diesels. keep that wix in, you'll be ok, but the next change I would suggest checking out fleetguard.

 

Many thanks for all of these answers, Texas heat might be a bit for this weight but I will try it out for a while.

 

I had it in my truck for about 5k miles... I didnt care for it too much and ultimately went back to dyno oil... mobil delvac IIRC. I thought the 5w-40 was too thin for the hot days here in the Sacramento area... we see temps in the 90's & 100's throughout summer. Going to be making the switch to Amsoil in about 2k miles and may install an amsoil bypass setup at the same time, cant wait for that.

 

So where is everyone finding the best prices for oil. (i.e. Rotella, Delvc, Amsoil, etc)

thanks for the help

 

If your summers are brutal, run 20w -50. In winter I have always run Rotella T 15W-40. Every 4,000 miles. Never had a problem from one temp extreme to another.


Good luck.

 

What's the matter with the Rotella T ? I've been using that since day one.

 

Not sure about the Rotella T but I was not impressed with the synth they have. went back to mobil delvac after the rot, then on to the amsoil... amsoil rocks

 

I have nothing against it, but the stuff has a horrid odor[:'(]

I used to get my oil from wally world, Delo 1300. but now I'm running AMSoil. you can hit up their website. become a preferred customer and save some cash