Mechanic says change oil

[DavidJones]

Thermostat? Was it bad? Could be the injection has been on the rich side for 2200 miles? He could have a point.

 

[JavierH19]

Oil turns slightly dark after just 2k miles "you gotta change it"

I'd ignore that.

 

[nomas]

Mechanic isn't asking to change it, he knows I do my own oil changes (that and tire rotations is about all I do myself)..... He's advising me to change it due to the color.

 

[JohnnyG]

The real question here is why is the thermostat being changed.

If you are experiencing overheat problems, it's likely NOT the thermostat.
Northstar engines were susceptible to head gasket failure, but RARELY did they fail in a way that would allow water into the oil. The common failure showed up as engine overheat due to exhaust gasses accumulating in the cooling system.

If you are having overheat issues, make sure there is full flow from the small rubber hose that comes from the top of the throttle body, and goes to the coolant reservoir. This was there to insure no air is in the cooling system.
If it is plugged, REMOVE the hollow bolt at the throttle body and clean it out. DO NOT use air to blow the stoppage back into the engine, it must be removed.

If you have full flow, and it spurts air periodically while the engine is running, you have a head gasket leak.

 

[JohnnyG]

By the way, use Dexcool with Bar's Stop Leak when you refill the cooling system. Do NOT put the stop leak in the reservoir, but in the lower radiator hose only.

 

[doublebase]

I don't get the calls for you to change mechanics . You said he's not trying to create business for himself so just be happy that he's trying to look out for you .

Yeah, I don't get it either. First off, a tech is only going to make a few bucks doing an oil change. I think the most I've ever seen a flat rate tech make on an oil change was .5 hours...and usually it was .3...and that included getting the car out in the parking lot, finding the keys, finding where it is parked, pulling it in, setting the lift up, going to the parts counter for a filter and plug gasket, doing the oil change, pulling the car out and parking it. That's not including checking tire pressures, and topping off fluids. By the time you're done you just lost out on three other jobs that you could have possibly made money on.

 

[fortyeightjake]

Like what? Beware upselling to an Oil-Karen who is willing to flex their lexicon and has nothing better to do?

He may learn that the color doesn't necessarily mean the oil is bad or over-contaminated and that it is still performing just fine. People learn new things every day.

 

[2strokeNorthstar]

I agree with Pontiac HO. Northstars have had issues with coolant in the oil, and with head bolts pulling out of their threads. He may have also made this recommendation NOT KNOWING how many miles are on the oil in question.

Mostly pre-2000 Northstars and those are mostly all dead by now. I'm surprised it's not leaking and burning oil fast enough to stay clean.

 

[ATex7239]

He may learn that the color doesn't necessarily mean the oil is bad or over-contaminated and that it is still performing just fine. People learn new things every day.

What makes you think he doesn’t already knows or would even care… If he get 5 of 10 people do an oil change with statements like that why would he want to change and potentially lose that low hanging revenue?

 

[nomas]

Reading comprehension ...

 

[fortyeightjake]

What makes you think he doesn’t already knows or would even care… If he get 5 of 10 people do an oil change with statements like that why would he want to change and potentially lose that low hanging revenue?

You're quite the optimist, so sorry for offending you.

 

[Lapham3]

What year Northstar? The later engines were much improved.

 

[ATex7239]

You're quite the optimist, so sorry for offending you.

Realist. None taken

 

[Bill7]

Cadillac Deville (4.6 Northstar 104k) is in the shop for a look over, fuel filter change, coolant flush, new thermostat. Mechanic says oil needs to be.changed because it's dark. OLM says 63% remaining life....oil was changed 2200 miles ago in January. Mobil 1 Extended Protection High Mileage, Mobil 1 EP filter.
Mechanic isn't asking to change it, he knows I do my own oil changes (that and tire rotations is about all I do myself)..... He's advising me to change it due to the color. Should I? Does color matter?

My normal OCIs are every 6 months unless i hit 5-7 k then I'll do it sooner.

The oil might be dirty / contaminated. If it looks dirty, I would change it.
You may wish to do an engine flush, and then check the new oil after the oil change how many miles it takes to get dirty looking.

 

[Dehaka]

Northstars have had a history of coolant showing up in the oil. Wondering if he’s seeing signs of that and he’s buying some time. Is the thermostat change due to an overheating issue?

No totally a preventive maintenance thing.

 

[Dehaka]

Thermostat change? So has the engine been running cold a lot on this oil change? That can certainly cause premature breakdown of the oil, with extra fuel making it past the rings and excessive water in the crankcase.

It's not unreasonable to think the oil got a beating. And the previous oil fill might have aswell, depending how long the thermostat was faulty and how bad it was. If so, that previous fill left nasties in the engine that this fill has to deal with aswell.

Nodthing wrong with thermostat. I swap em out on all my cars after 4 years no matter what. Not a necessary nepair..... Just preventive maintenance i do.

 

[Dehaka]

Why the T- stat change? Just PM? OEM T-stat?

If car has been running well, leave the oil in.

It's M1 EP - leave it and continue with the regimen you explained in post #1

You would be doing the car and yourself NO FAVOUR AT ALL by changing the oil quite early.

- Ken

Yes PM. **** thing was $45. Over double price of my other 4 t stats i replace annually. Genuine GM.

 

[Dehaka]

The oil might be dirty / contaminated. If it looks dirty, I would change it.
You may wish to do an engine flush, and then check the new oil after the oil change how many miles it takes to get dirty looking.

OK not a bad idea. Recommendation for good flush product?

 

[350Rocket]

Cadillac Deville (4.6 Northstar 104k) is in the shop for a look over, fuel filter change, coolant flush, new thermostat. Mechanic says oil needs to be.changed because it's dark. OLM says 63% remaining life....oil was changed 2200 miles ago in January. Mobil 1 Extended Protection High Mileage, Mobil 1 EP filter.
Mechanic isn't asking to change it, he knows I do my own oil changes (that and tire rotations is about all I do myself)..... He's advising me to change it due to the color. Should I? Does color matter?

My normal OCIs are every 6 months unless i hit 5-7 k then I'll do it sooner.

My oil is still a nice light gold, still transparent when I'm down to 7% oil life....4100 miles in 3 months. Lots of starts and lots of idle time, but also lots of highway.
If it's getting dark by 63% it's probably either cleaning out deposits, or has blowby.

 

[Deleted member 89374]

Should I? Does color matter?

Did the jug say "Triple Action" on it? What was the previous oil you used before this?