3 odd little questions about my new truck w/6.7 CTD with 3000 miles

[Jeff400650]

1. When I check the oil on the dipstick, it looks very black. On other vehicles the oil always still looks amber when it is just a thin film on the dipstick, even if it is old and black when drained. Is this a diesel thing? Or?

2. I've noticed when highway cruising on level ground, with 80 degree air, at 75 mph, that the coolant and oil temps constantly cycle from a low of 185 degrees to a high of 199 degrees. They stay about 186 for 2 or 3 minutes, then ramp up close to 200 for a minute or two, then back dow, over and over. AC on or off does not matter. I'm curious what is going on there.

3. What are these little square things in the headliner? There are 6 of them. They look like tweeter speakers, but I can't detect any sound from them, and I don't think the Tradesman trim level would have such a fancy sound system.

 

[Burla]

Diesels make oil black super fast, but the oil is still good. You can always do a uoa from blackstone to learn about oil life. This is why bypass setups are so popular on diesels.

t stat lets coolant get so hot before opening. It opens and closes to keep your coolant in the correct range.

 

[Travelin Ram]

Those are microphones for active noise cancellation or ANC.

And possibly monitoring devices for the NSA.

 

[MADDOG]

Black oil is a diesel thing.

My coolant & oil temps swing a bit too but not quite that much. I suspect it's a combination of the thermostat opening and closing plus cooling fans operating.

Those are headliner vents in your Tradesman. For upper level trims some have rear tweeter speakers and a smaller grill in front for a microphone.

 

[Jeff400650]

Thanks for the feedback.

Now for another question... I hear a frequent seemingly random extra motor noise. Often when the driving before the motor is fully warmed up, but at other time too, usually in lower gears when getting up to speed. It almost sounds the the motor is over revving, but the tac does not surge. It could be an electric cooling fan turning on and off?

I love the truck, but it has some new-to-me little quirks.

 

[Darron]

I just purchased my 2020 Ram 2500 6.7 L CTD 6-8 weeks ago. Checked oil today... not quite 1300 miles on it. This is how it looked. Quite black for such limited miles. I had to do some research to determine that's normal for diesels.

Still makes me want to change it. Also thinking about installing a bypass filter.



And watch what you say while in the cab... they are listening.

 

[OLEJOE]

That oil is clean compared to mine. It’ll get darker. Trust me.

 

[Darron]

Oh, I know. The point is that I wasn't even to 1300 miles yet. No way I'm waiting until ~15k miles to change that oil.

 

[jejb]

You'll get used to it. When I change the oil in the 8.3 Cummins in our diesel pusher (over 20 quarts), it looks like that pretty much right away.

The looks of an oil, especially in a diesel, has nothing to do with its ability to perform at spec.

 

[HDGoose]

One thing California got right was to sue the quickie lube places for telling folk to change their oils at 3000 miles. 40 years ago with the oils of the day and carburetors, maybe. But not with modern oils, filters and fuel injection.

My 2013 RAM 2500 diesel got changed at 75% according to the EVIC. At 100,000 miles I sent off an oil sample for testing and everything was great.

I do the same with my 2020 RAM 3500 diesel.

 

[mtnrider]

Oh, I know. The point is that I wasn't even to 1300 miles yet. No way I'm waiting until ~15k miles to change that oil.

That oil is perfectly fine. Just because it is black means nothing. If you had an oil analysis done on it you would see it is fine. Been doing 15K oil changes on mine since day one and even at 15K the oil has plenty of life left in it (verified via oil analysis)

In diesels the oil will go black as soon as you run it. Don't worry about it , Completely Normal!


.

 

[chri5k]

I change the oil & filter in my 2016 every 7500 miles.

Since you have a 2020 with the CP4 high pressure pump, you may want to consider a fuel lubricity improvement additive. There have been some catastrophic failures of those pumps across multiple brands of engines. There is a school of thought that the poor lubricity of the newer ULSD is a contributing factor. Something like Opti-Lube XPD improves the lubricity of the fuel and can help save the pump.

Here is a thread on one of these failures.
https://www.ramforum.com/threads/2020-ram-2500-cp-4-failure.161696/

 

[Gr8bawana]

I change the oil & filter in my 2016 every 7500 miles.

Since you have a 2020 with the CP4 high pressure pump, you may want to consider a fuel lubricity improvement additive. There have been some catastrophic failures of those pumps across multiple brands of engines. There is a school of thought that the poor lubricity of the newer ULSD is a contributing factor. Something like Opti-Lube XPD improves the lubricity of the fuel and can help save the pump.

Here is a thread on one of these failures.

Changing the oil at 7500 miles is a complete waste of $$. Just follow the owners manual recommendations.
Additives are also a complete waste of $$ as well. There is no independent scientific proof that they help in any way. Only the outrageous claims made by the additive makers and their own "testing".
There is a reason the owners manual does not say any additives are needed.

 

[chri5k]

Changing the oil at 7500 miles is a complete waste of $$. Just follow the owners manual recommendations.
Additives are also a complete waste of $$ as well. There is no independent scientific proof that they help in any way. Only the outrageous claims made by the additive makers and their own "testing".
There is a reason the owners manual does not say any additives are needed.

Actually, there is scientific evidence that Opti-Lube and other diesel fuel additives improves fuel lubricity and reduces wear. https://www.jatonkam35s.com/DeuceTechnicalManuals/Diesel_fuel_additive_test.pdf

As far as oil change intervals, that turns into a near-religious debate. All I'll say is that it my money to waste thank you.

 

[Gr8bawana]

I'll keep saying additives are not needed because from the info you provided you are wasting $$ on a product to use because the fuel at the pump MIGHT not have sufficient "lubricity" from the manufacturer.
That must be why there are million upon millions of diesels out there using ZERO additives going strong after hundreds of thousands of miles with no problems.
Feel free to keep wasting your $$.

 

[tjfdesmo]

I'll keep saying additives are not needed because from the info you provided you are wasting $$ on a product to use because the fuel at the pump MIGHT not have sufficient "lubricity" from the manufacturer.
That must be why there are million upon millions of diesels out there using ZERO additives going strong after hundreds of thousands of miles with no problems.
Feel free to keep wasting your $$.

I am not advocating for additives, but you have a truck with the old reliable CP3, not the notorious POS CP4.

 

[Greyhound240]

Thanks for the feedback.

Now for another question... I hear a frequent seemingly random extra motor noise. Often when the driving before the motor is fully warmed up, but at other time too, usually in lower gears when getting up to speed. It almost sounds the the motor is over revving, but the tac does not surge. It could be an electric cooling fan turning on and off?

I love the truck, but it has some new-to-me little quirks.

 

[Greyhound240]

Thanks for the feedback.

Now for another question... I hear a frequent seemingly random extra motor noise. Often when the driving before the motor is fully warmed up, but at other time too, usually in lower gears when getting up to speed. It almost sounds the the motor is over revving, but the tac does not surge. It could be an electric cooling fan turning on and off?

I love the truck, but it has some new-to-me little quirks.

That is your clutch fan you are hearing.
After your engine warms up a bit, you won’t hear it.