When should I have my oil changed?

[TCurray]

I have a 2004 1500LD Sierra Crew Cab 4x4. Is it safe to follow the owner's manual and not change the oil until the Driver Information Center (DIC) on the dash tells you to? I've been drilled all my life being told to change my oil every 3,000 miles. I just went over 4,500 and nothing from the DIC yet. I'm getting a little nervous. The dealer is also sending me notices stating that "they (not the manufacturer) recommend comming in for an oil change." Is the dealer just wanting my money? Is it better to be "safe than sorry", or save a lot of money over the life of the truck hoping GM knows what they're doing with the DIC?

[TweakedGM]

I change my oil every 3000 miles the date which ever comes first.

[GMCTech]

GM says you can wait to change your oil until the change engine oil light comes on.

It is a very detailed system, and we have a few customers that wait until then, in pick-ups that's just about 6000 miles or so in most cases depending on your driving habits.

The only thing that isn't happening is that your grease fittings aren't getting any grease.

We still suggest to customers that they change their oil every 3000-4500 miles (we put a 3000mile lube sticker in the window) because your motor may live 200k miles changing your oil twice a year but your ball joints wont.

In most cases, our customers dont choose to grease their own vehicles between services.

Hope this helps.

[TCurray]

Thanks GMCTech...

Can you give any insight into some other issues I am seeing?

1. There is a "clunk" that is happening in what seems to be the rear end when shifting from 2nd to 3rd or from drive to reverse (automatic). I can even get under the truck and grap the driveshaft with my hands and rotate it just as the drive to reverse and the clunk will occur.

2. I have had two experiences where I have stopped at an intersection and stepped on the gas to go. The truck RPMs went up, but the truck did not go. After about 2-3 seconds, the truck "grabbed" and took off. This happened within the first two weeks I owned the truck and has not happened since.

3. There is some type of strain vibration noise that occurs when trying to maintain speed in overdrive between 40 and 50 mph. I can make it happen most consistantly if I put the truck on cruise at approximately 43 mph and let it maintain the speed on a slight uphill grade.

4. The air compressor makes a rather loud "swishing" noise constantly while the AC is on. Very annoying.

5. There are black plastic sheets that keep slipping out from under the door panels. Improperly installed, or forgotten to be removed?

As requested, any insight would be greatly appreciated.
Thanks...

[AtleyJackson]

I have to agree with GMTech on this one. You can wait for the light. The only thing you have to grease the ball joints. I will tell you I run 5w30 fully synthetic Mobil one. I change it every 3000 to 6000 (when the light comes on) try to do every 3000. I grease every thing possible. The truck is a 2001 with 140k and running strong. If you maintain it will run.