First Oil Change ?

05_2500HD · April 14, 2005

05 2500HD 6.0, 450 miles....When should I do my first oil change ? I plan on using Mobil 1 synthetic, not sure which one to use.......I've used the SUV 5-40 before in the past but isn't this too thick ?

Thanks !

Machine · April 14, 2005

05 2500HD 6.0, 450 miles....When should I do my first oil change ? I plan on using Mobil 1 synthetic, not sure which one to use.......I've used the SUV 5-40 before in the past but isn't this too thick ?

Thanks !

<{POST_SNAPBACK}>

Hi -

You should get a lot of feedback on this question. So here's mine:

Because it is so new, I would run it to 3000 miles before the change over to synthetic. But in all reality, you can switch over right now. I've done both. The new gas engines that we have in our trucks do not require the detailed break-in that the older engines demanded.

As far as the synthetic goes, and depending on your climate, I would use 5w-30 as suggested in the owners manual

snoman · April 14, 2005

05 2500HD 6.0, 450 miles....When should I do my first oil change ? I plan on using Mobil 1 synthetic, not sure which one to use.......I've used the SUV 5-40 before in the past but isn't this too thick ?

Thanks !

<{POST_SNAPBACK}>

Hi -

You should get a lot of feedback on this question. So here's mine:

Because it is so new, I would run it to 3000 miles before the change over to synthetic. But in all reality, you can switch over right now. I've done both. The new gas engines that we have in our trucks do not require the detailed break-in that the older engines demanded.

As far as the synthetic goes, and depending on your climate, I would use 5w-30 as suggested in the owners manual

<{POST_SNAPBACK}>

This is a subject of great debate but I would change the oil around 500 miles for the first time but I would not switch to synthetic oil until you get at least 5000 miles or more on it. Becaue the engine will break in quicker and better on regular motor oil. Also regular motor oil is getting pretty good and if you use quality oil and change it every 3000 miles or less, you are not really giving much up to synthetics. The trick to long life is frequent and regualr changes of oil though syn has advantages in extremely hot (above 100F) or extremely cold climates (below 10 or 20 below). Also some swear by it is differentails but again I see no advantage over 75w90 dino oil unless you are dealing with extremes again. Do change your rear axle oil with first oil change if you plan to keep it for a while as it is breaking in too and it has no filter back there.

Bart2500HD · April 14, 2005

I would wait until 1500 miles, change with regular oil, and then switch to synthetic at around 5000 miles if you want to. For me, I can't see spending the extra $$ for synthetic. Especially when my truck takes 6.5 quarts per oil change and I generally have to add a quart between changes.

05_2500HD · April 14, 2005

Funny how Mobil 1's website says it's a myth that you have to wait.....Corvettes come filled with synthetic from the factory.....

snoman · April 14, 2005

Funny how Mobil 1's website says it's a myth that you have to wait.....Corvettes come filled with synthetic from the factory.....

<{POST_SNAPBACK}>

They want to improve sales too. The theory is the synthetic longer chain molecules reduce friction so the reduce wear and increase the time that break in takes and the reason that the vette comes with it is because of very high oil temps in that engine in its tight compartment when you "run" it hard. Regular oil starts to cook out at 275 to 300 degrees and Mobile 1 will take about twice that temp before it cooks out and breaks down. When I rebuild a engine myself I run it but a few hours on first oil then change it to get any grit left over from rebuilt that was not cleaned out and then change it again around 500 to 700 miles

Machine · April 14, 2005

Funny how Mobil 1's website says it's a myth that you have to wait.....Corvettes come filled with synthetic from the factory.....

<{POST_SNAPBACK}>

As does Mercedes, Ferrari, Lambo, Jag, etc. The myth with todays technology is that these motors need a real break-in period , and, for example, dino oil helps the rings seat better/ sooner than synthetic.

snoman · April 14, 2005

Funny how Mobil 1's website says it's a myth that you have to wait.....Corvettes come filled with synthetic from the factory.....

<{POST_SNAPBACK}>

As does Mercedes, Ferrari, Lambo, Jag, etc. The myth with todays technology is that these motors need a real break-in period , and, for example, dino oil helps the rings seat better/ sooner than synthetic.

<{POST_SNAPBACK}>

and those car are a lot more precision built too and some are even pre run in before you even get them too.

Frank S · April 14, 2005

What 05 2500HD and Machine said.

I've been changing to synthetics on the first change for a decade now and never have had a lubrication or "break in" problem such as rings, seals, guides, etc.....

I'll stick with what's been working for me and that's a change to synthetices within 2000 miles.

mmmikkke · April 14, 2005

I'd change to M-1 5W-30 now. Take every step to stop piston slap from developing. Much more important than whether something breaks-in with a ying versus a yang.

snoman · April 15, 2005

I'd change to M-1 5W-30 now. Take every step to stop piston slap from developing. Much more important than whether something breaks-in with a ying versus a yang.

<{POST_SNAPBACK}>

Piston slap is not going to be prevented by the use of mobile one or not because if they are improperly sized from day one, (and that is what causes the slap to begine with) no oil in the world is going to fix that.

496 CUBIC INCHES · April 15, 2005

Change the factory fill at 500 miles and then again at 1000 miles. After that run whatever you want. The M1 5-40 is NOT too thick. GM wants you to run a 5-30 because of CAFE (Corporate average fuel economy). GM (all manufacturers) get hit with a fine for producing vehicles that don't get certain MPG. By running a 5-30 GM is hoping to get every last tenth of a MPG.

There are some that say to use the 5-30 because the engineers at GM designed the engine to run on 5-30. Thats a bunch of BS if you ask me. If the engineers at GM are so brilliant,why did they design an engine with pistons that don't fit,or engines that have intake gasket leaks all the time,or CRAPPY brakes on the OBS trucks.

mmmikkke · April 15, 2005

I'd change to M-1 5W-30 now. Take every step to stop piston slap from developing. Much more important than whether something breaks-in with a ying versus a yang.

<{POST_SNAPBACK}>

Piston slap is not going to be prevented by the use of mobile one or not because if they are improperly sized from day one, (and that is what causes the slap to begine with) no oil in the world is going to fix that.

<{POST_SNAPBACK}>

Piston slap is not happening on day one, to begin with. It happens typically after a few thousand miles.

How is it that it only shows up after a few thousand miles. Could it be...wear? Or scoring, or galling?

I submit that you don't really know why it takes a few thousand miles. Correct me if I'm wrong.

I stand by my comment.

snoman · April 15, 2005

I'd change to M-1 5W-30 now. Take every step to stop piston slap from developing. Much more important than whether something breaks-in with a ying versus a yang.

<{POST_SNAPBACK}>

Piston slap is not going to be prevented by the use of mobile one or not because if they are improperly sized from day one, (and that is what causes the slap to begine with) no oil in the world is going to fix that.

<{POST_SNAPBACK}>

Piston slap is not happening on day one, to begin with. It happens typically after a few thousand miles.

How is it that it only shows up after a few thousand miles. Could it be...wear? Or scoring, or galling?

I submit that you don't really know why it takes a few thousand miles. Correct me if I'm wrong.

I stand by my comment.

<{POST_SNAPBACK}>

When engine is built, a few thousands of wear for breakin is figured in when sizing the engine bores and pistons. It take a surprizing little amout of extra clearance to create piston slap so when the engine is new and the cyclinder is rough and the rings not setting fully it might not slap yet. But the cylinder must wear a bit to seat rings properly and the piston wear a bit too during break in as it polishes it self a bit in the bore. There is no avoiding this as this wear in will take place. If you use SYN oil to delay break in you are not saving anything because the engine wll make its best HP and MPG when fully broken in and running smoothly. Your idea has merit but is based incorrectly. GM has blamed sticky piston rings for then problem and while they can sometime aggrevate piston slap, they will not cause it if the piston is properly sized to begin with. I have seen some real oil burning engines with bad rings that never had a bit of piston slap. I have a old Jeep with a AMC engine and it has had some piston slap for about 15 years now for a few minutes after a cold start but it always goes away when it warms up some.