did my first oil change today at 3500 miles . i used mobil delvac 1 sae 5w - 40 .
after reading my owners manual tonight i saw it says to use sae 15w - 40
or sae 10w - 30 . the manual says the 5w- 40 is for temperatures below 0 degrees. i live in california and will never see below 0 temperatures. did i just make a big mistake ?

Not BIG, but change it to 15w40 soon.

Mobil 1 Delvac is an excellent oil in my opinion and is ideal for a Duramax. I wouldn't worry a bit about your decision in oil. You certainly haven't harmed your engine in any way in my opinion. While I see nothing wrong with running 5-40 in your climate, I really don't think you'll benefit from it. With the warm temps you encounter, I'd prefer 15-40.

In addition, you might reconsider using a full synthetic such as the Delvac after only 3500 miles. The general consensus seems to be "Wait until 5,000 -- 10,000 miles before switching to a synthetic." However, I'm not convinced one way or the other. A lot of vehicles are coming from the factory with full synthetic these days. If it was me, I'd leave the 5-40 in for until your next scheduled change, and keep a close eye on the dipstick during that time. If the engine doesn't consume any oil during this time, I'd switch to a full synthetic 15-40 the next change. If it does start to consume more than you'd like, I'd go back to a 15-40 petroleum oil for several more thousand miles before switching to synthetic.

This is just my opinion. I'm a believer in synthetics, but a lot of very knowledgeable people don't feel that they're worth the extra cost. If you'd like to really research oil, visit www.bobistheoilguy.com and go to the forums. Those guys really know oil!

i love the diesel place !!!!!!!!!!!!!!!!!!!!!!!!!! i post and i get answeres 2 minutes later. any other opinions on this ?

Stick with the Mobil Delvac 1 5w40 if you don't mind paying the price. Most will say it is the best oil money can buy.

Lots of people here run 5w40 synthetic year around, including myself.

I also live in OC. Have been using Mobil Delvac 1 since 10K miles (truck now has 23K miles). This is an excellent oil. Mobil Delvac 1 is packaged for Large Commercial Trucks. It is fully synthetic.

An equivalent oil now sold at Walmart (only place I have found it so far in OC) is Mobil 5W-40 Truck and SUV.

By the way, if you look at the Diesel Supplement, the 5W-40 range oil is good for less than 0 degF and also exceeds 100 degF. So it truely covers the entire range.

Look on the bright side, your ready for a trip to Alaska.

There is a number of LB7's which would trade your 5w-40 for their 10 quarts of oil pan diesel oil. ):h

I agree, no damage is done, especially if you're running commuting miles. But for me I'd change the oil to relieve my mind of thinking about it. But get a fomoto drain valve before changing it and you have a real excuse to drop the oil.:)

Check out http://www.bobistheoilguy.com

Look on the bright side, your ready for a trip to Alaska.

We use 0-40 up here in the far north!!!:p

On second thought change it and send it to me. I just checked forecast below for my area tomorrow.

" Monday: Mostly Cloudy With A Chance Of Snow. Highs 30 To 35. Northwest Winds 15 To 25 Mph With Gusts To 35 Mph. Chance Of Precipitation 30 Percent.
Monday Night
Partly Cloudy. Cooler. Lows 10 To 15. Northwest Winds 5 To 15 Mph. "

diesel man,

You can do a search for "what type oil" on the forum and probably have enough reading to keep you busy for hours. . . There are widely varying opinions on the subject. There's even a poll or two on the subject. Plenty of choices, plenty of opinions. Sometimes things like that make it hard to even come to your own decision as to what's best. It does help you figure out what isn't so good, though. Probably any of the choices that are recommended on the forum by a couple different people would be fine.

Dennis

Dieselman, I agree with you about this site 100%, I'm new to the diesel thing myself and have questions/concerns, the guys on this forum have lots of info or can direct you/me in the right direction :D

Running Delvac 1 is fine.

The "5" in "5W-40" is the equivalent cold flow viscosity. That oil will perform just as well in the OC as it will in the WY.<O:p</O:p

Most of the synth's have an extended viscosity range which is why you see Delvac 1 as a 5W-40 and the Delvac 1300, (Dino), as 15W-40.<O:p</O:p

Go over http://www.bobistheoilguy.com (http://www.bobistheoilguy.com/) like Max Power said and read up on the pro's and con's of synth over dino.<O:p</O:p

And Welcome to the finest Diesel forum around! :ro)

Thanks Everyone . I Have Been Told The Grey 1 Gallon Container My Oil Came In Is Actually The 15w But Marked 5w. Not Sure If Is True Or Not. On The Container It Says " Mobil One Synthetic 5w-40 Delvac For Heavy Duty " I Think I Will Be Ok....

You got the 5w-40 in the grey container. Mobil Delvac 1300 (Dino) 15w-40 is in a black container. I have not seen a synthetic 15w-40 diesel engine oil. All of the synthetic diesel oils that I have seen are 5w-40.

I run Delvac 1 5w40 year round in my 2002, and will have the 2005 flushed out and ready for Delvac soon. I've changed and sampled the LLY at 85, 335, and 900-ish miles so far.

Don't worry you will be fine. Stick with the Delvac year round it is the best oil money can buy and it will protect much better at higher temps, especially in the turbo housing. It is expensive but worth it IMHO.

Welcome to the club...........:)

You got the 5w-40 in the grey container. Mobil Delvac 1300 (Dino) 15w-40 is in a black container. I have not seen a synthetic 15w-40 diesel engine oil. All of the synthetic diesel oils that I have seen are 5w-40.Amsoil makes a 15W40 synthetic diesel oil. Works great in my boat, too.

Amsoil makes a 15W40 synthetic diesel oil. Works great in my boat, too.
I think the jury is still out on this actually being a "true" synthetic.............:D

Proper engine oils: After years of testing and seeing hundreds of oil analysis from fleets in different areas I find the following will produce the best oil analysis. Use 15W40 below +32F and straight 30 weight above +32F. Both oils must be API certified CF-2 or CF-4 or above. Many people do not understand engine oils or proper usage. You can not rely on manufacturers or oil company specifications. The manufacturer EPA certifies the engine on a lighter oil to achive a higher fuel economy reading and the oil company will push what they want. Once the engine is EPA certified on a given oil the manufacturer is not allowd to suggest using a different weight oil. The only correct method in selecting the correct engine oil is by oil analysis and I would send the samlpe to a independant testing lab not the oil company. In most cases a high multi viscosity will cause deposits on the rings and possible ring sizure. A 5W50 is a 5 weight base oil with viscosity improvers to change it to 50 weight. Viscosity improvers are basically polmers that change viscosity when subjected to heat. The ring temp. on a diesel engine is five times higher than its gasoline counterpart and one funtion of oil is to seal the piston to the cyl wall. When the oil migrates up the piston and contacts the ring the polmers congeal forming a deposit and over time ring sizure. This condition will accelerate in high ambiant temps. . Last summer I had three engine oil analysis preformed on three of our test trucks. One truck is a 2001 6.6 Duramax dynod at over 700 HP and the iron in oil content was 3 PPM using straight 30 weight Chevron Dello 400. The same truck two months later with 15W50 Dello had 24 PPM of iron in the oil. In almost every fleet I visit that preformes oil analysis on a regular basis has far more engine ware using multi viscosity than straight 30 weight in high ambiant temps. Again, do not believe me, the oil salesman or the manufacturer, beleive the oil analysis!!

I think the jury is still out on this actually being a "true" synthetic.............:D
This my friend is true, but it is as close as there is today.;)

O Reilly's carries the Mobil 5w-40 Truck/SUV, a few cents more, but our Walmart has had ONE quart of this oil, the same quart for about two months now, said they wouldn't be stocking it anymore. ??

This my friend is true, but it is as close as there is today.;)
You mean other than Delvac 1 right?? :D

You mean other than Delvac 1 right?? :D
Delvac 1 comes in 15W40? :confused:

Delvac 1 comes in 15W40? :confused:
No only 5W40.

I missunderstood you. I thought you were speaking about all "synthetic" oils not a 15W40 specifically.

Then, yes Amsoil is as close as you are going to get in the 15W40 variety...........

No only 5W40.

I missunderstood you. I thought you were speaking about all "synthetic" oils not a 15W40 specifically.

Then, yes Amsoil is as close as you are going to get in the 15W40 variety...........
Yup, I was referring to 15W40 only. Sorry for the confusion.

I agree with most of the post in this thread. If you can afford it though, stick with Mobile Delvac 1. It will handle all temps just fine. And I think it is the best oil out there.

Wow, looks like I need to wake up. Must have Thanksgiving turkey on the brain. I deal with Mobil (not Mobile) every day and I still don't know how to spell it.

Amsoil makes 2 15w40 Diesel oils. Product code AME is a full synthetic Heavy Duty Diesel and Marine motor oil. Product code PCO is a 15w40 synthetic blend. Also available are 5w30 and sae 30 as full synthetics. For complete list of products email ripell1@msn.com

You didn't mess anything up. Know a lot of folks running the Mobil 5-40 all the time. I run Shell Rotella 15-40 and change every 5,000 miles. Meets or excees GM specs. and keeps the warranty in effect.

Amsoil all the way...gotta support the local economy:D

Delvac 1 is year round oil. I've run it since 2,200 miles (now at 41,000). All UOA have been fine. It flows better at ultra low temps, but once the engine is warm it's 40 weight oil just like the others.

TC

did my first oil change today at 3500 miles . i used mobil delvac 1 sae 5w - 40 .
after reading my owners manual tonight i saw it says to use sae 15w - 40
or sae 10w - 30 . the manual says the 5w- 40 is for temperatures below 0 degrees. i live in california and will never see below 0 temperatures. did i just make a big mistake ?
You absolutely did use the wrong oil. Tell you what, since you've damaged your motor, I think you should sell your truck to me at a very discounted rate and put that down on another.....:D :D

You'll be fine.......I'm an Amsoil dealer and the "mistake" oil is very good oil. Hell, you should see some of the "mistakes" I've seen......:( I'm using the amsoil syn/blend in the engine. Good balance between price and protection.

I use amsoil 5w-30 hd diesel oil change filter every 7 k oil every 14k oil analysis shows no problems now have 23k 04 lly cc 4x4 sb