DIC oil change and ticking noise03 Trailblazer 4.2

Bullethole · April 26, 2005

I have been using the oil change computer to schedule oil changes. No towing, mainly hiway and some in town. Computer tells me about every 10-12k. Can this be true? For 40 years I have been a 3-5k guy. Also following instructions I found in this forum my ticking stops when I remove the plug from the top of the radiator. How long before the fan clutch gives up?

Bullethole · April 28, 2005

I am out of warranty. Can I expect ot be charged for computer updates? My mirrors are acting up too.

Yes, those updates would cost you. The only PCM updates that would be covered by warranty at this point are updates related to emissions. Those would be covered for 8/80 just like the PCM and catalytic converter. The fan update is not an emission related update.

On average, I'd say it'd cost you an hour labor.

<{POST_SNAPBACK}>

Just a short rant here. It would seem that a software update would fix something that was not right to begin with. I know when I buy a product from Microsoft the updates and fixes are free. I understand the labor part in the dealers case but I think GM should eat that.

snoman · April 28, 2005

Computer tells me about every 10-12k. Can this be true?

Yep, that can happen. If you're uncomfortable with that, you can always change it earlier.

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It is generally in GM's (and Ford and Dodges) best interest for you not to change it often because even with very little maintance, the engine will last the life of warranty but how well you maintain it will effect how well it runs several years from now after warranty is gone. If it runs poorly and/or uses oil you are more likely to replace the vehical than keep it. Kinda planned that way to encourage replacements. The last thing they want to do is make a car or truck last 10 years of more on average because that would really hurt sales after a while. 3K to 4K miles is a much more realistic interval if you plan to keep it for a while.

USA1Fan · April 28, 2005

Computer tells me about every 10-12k. Can this be true?

Yep, that can happen. If you're uncomfortable with that, you can always change it earlier.

<{POST_SNAPBACK}>

It is generally in GM's (and Ford and Dodges) best interest for you not to change it often because even with very little maintance, the engine will last the life of warranty but how well you maintain it will effect how well it runs several years from now after warranty is gone. If it runs poorly and/or uses oil you are more likely to replace the vehical than keep it. Kinda planned that way to encourage replacements. The last thing they want to do is make a car or truck last 10 years of more on average because that would really hurt sales after a while. 3K to 4K miles is a much more realistic interval if you plan to keep it for a while.

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Not really. The 4.2 holds 7 quarts of oil (quite a bit more than our truck V8's) and is an inline engine. If you follow the manual's recommendations you should change it at least once a year or whenever the OLS tells you, whichever is earlier.

I let my TB get to about 8k with moderate city / highway driving and no real extreme conditions before I changed it because I was getting ready to move over 1000miles towing our car with all 4 family members and our luggage aboard. I was using Mobil1 for the added sense of security, but the oil itself was still looking fairly clean when I changed it.

GM-Tech · April 28, 2005

I know when I buy a product from Microsoft the updates and fixes are free.

Is this where I post the "If Microsoft built cars" comparison? Ah well, I will anyway...

If Microsoft Built Cars...

1. A particular model year of car wouldn't be available until after that year instead of before it.

2. Every time they repainted the lines on the road, you'd have to buy a new car.

3. Occasionally your car would just die for no reason, and you'd have to restart it. For some strange reason, you'd just accept this.

4. You could only have one person in the car at a time, unless you bought a Car 95 or a Car NT. But then you'd have to buy more seats.

5. Sun Motorsystems would make a car that was powered by the sun, twice as reliable, and five times as fast - but it would only run on 5 percent of the roads.

6. The oil, engine, gas, and alternator warning lights would be replaced with a single "General Car Fault" warning light.

7. People would get excited about the "new" features in Microsoft cars, forgetting completely that they had been available in other cars for years.

8. We'd all have to switch to Microsoft gas.

9. The U.S. government would be GETTING subsidies from an automaker, instead of giving them.

10. New seats would force everyone to have the same-size butt.

GM-Tech · April 26, 2005

Computer tells me about every 10-12k. Can this be true?

Yep, that can happen. If you're uncomfortable with that, you can always change it earlier.

As for the fan clutch... I assume you mean you disconnect the electrical connector and the clicking stops? There's an updated PCM calibration that corrects this. Here's the details on the cause...

This condition may be caused by the electro-viscous fan clutch control function of the Powertrain Control Module (PCM) attempting to keep the fan speed between 300-600 revolutions per minute (RPM). At idle, the cooling fan speed will drag to approximately 500 RPM then oscillate between 300 and 600 RPM. When the fan speed drops below 500 RPM, the PCM will pulse the fan control solenoid. The pulsing of the solenoid is the cause of the ticking noise.

GM-Tech · April 26, 2005

And by the way, if your dealer is not familiar with this fix yet, since it just came out at the beginning of this month, refer them to TSB# 05-06-02-004.

Bullethole · April 26, 2005

I am out of warranty. Can I expect ot be charged for computer updates? My mirrors are acting up too.

GM-Tech · April 27, 2005

I am out of warranty. Can I expect ot be charged for computer updates? My mirrors are acting up too.

Yes, those updates would cost you. The only PCM updates that would be covered by warranty at this point are updates related to emissions. Those would be covered for 8/80 just like the PCM and catalytic converter. The fan update is not an emission related update.

On average, I'd say it'd cost you an hour labor.

Bullethole · April 28, 2005

All of that is true about MS. Even though I am using one at this moment I believe the computer is the right and left hand of the devil. I have this fear that I will get in my TB one day and the computer will lock the doors, turn on the heat, run my seat all the forward into the steering wheel, crank up the Bose on arap station and then fire the air bag. By the way I am using Mobil1 and Wix filters.

USA1Fan · April 28, 2005

I work with computers, and have several at home (only 1 is hooked up since my last move, since the local broadband connections miss the final mile to my house at the moment and that was my only real motivation for multiple compluters, aka "online games" ). So I've seen that before, but it's just as funny this go around as it was the first.