Long Idle time, new OCI?

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I've recently started in a new career field in which I drive 50 miles to the location, sit idling 10-12 hours, then drive 50 miles back.

I normally change the oil in my Crown Vic every 3000 miles. I remember reading somewhere that Ford recommends accounting for 25 miles per idle hour. With that being said, each day would be the equivalent of 350-400 miles. 4 work days a week makes an oil change every other week, if I were to try to stick with my normal OCI. I know the modular 4.6 is usually easy on oil, so the 3000 mile OCI isn't a necessity.

Should I factor in the idle time and just go for a 6000 mile equivalent, moving to monthly oil changes? Should I stick with actual mileage and not worry about the idle time? Or, should I just go to a time based oil change (every 3 months, etc) instead?

I'm currently running Castrol Magnatec 5w30 (local DG clearanced for $2 a quart to me) and a Fram Ultra. I've gone 2 weeks of work on it and I'm starting week 3 on Friday.
 
I would say YES. Especially due to idling isn't the best thing for an engine for that long of a time. The 50 mile drive each way will certainly help to burn off any fuel dilution. Your best driving is when you drive home 50 miles and drive 50 miles to work again the next morning.
Are you in law enforcement? 👮‍♂️ If so, thank you.
Yes, I'm a Peace Officer and I'm using the Crown Vic on "extra jobs." Thank you for your support.
 
Would it be worth investing in an oil that’s a little more “high end”, like HPL or Amsoil? I usually don’t suggest boutique oils, but for the right application or someone that wants the ultimate, maybe this would be a worthy investment?

And you’re in a warm climate; to idle like that in some of the temps that you experience?? Wow, that’s a tough task for an oil and cooling system. I’d probably get myself a used oil analysis at 6,000 miles using one of the boutique brands. Just my opinion. I mean, you’d be one of the ultimate customers for those brands. If I owned a company like Amsoil or HPL, I’d give you a free case, and ask you to submit your UOA. Great free advertising. Especially if it did well. IMO. Plus you’re law enforcement. Can’t get any better than that.
 
I'd look into an hour meter, and change oil based on hours not miles. If you go with the 25 mph figure that would put you at about 200 hours for a 5K OCI. Maybe one of our fleet maintenance guys can weigh in with an hourly OCI figure for a passenger car. With an good extended drain oil you could stretch it out a bit more than 200 hours. Combine that with a UOA with TBN or two and you'll have the perfect OCI.
 
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A monthly OCI schedule makes sense, given Ford’s 25 miles per hour idled figure. This would be a good use of an oil analysis to confirm or adjust the monthly OCI, since you can’t really go by the odometer.
 
Not sure of your mechanical ability but you are basically running a cop car assigned to a detail. I understand you don't have a police fleet crown vic but under the circumstances, you can add an hour meter along with an oil cooler. The oil cooler will substantially reduce the negatives of long idle times. Wouldn't know for sure but I'd say you would be a-ok with oil like Mobil 1 EP 5-30 or the same in 40 weight; 5k equivalent OCI using the hour meter.......

Double check me on this as it's been a long time (2000) since I was in a Crown Vic. IIRC the addition of the oil cooler was the only mitigation tool added to deal with long idle times. Times have a changed over the last 2 decades so if I'm wrong others will let us know so and the why behind it.
 
Not sure of your mechanical ability but you are basically running a cop car assigned to a detail. I understand you don't have a police fleet crown vic but under the circumstances, you can add an hour meter along with an oil cooler. The oil cooler will substantially reduce the negatives of long idle times. Wouldn't know for sure but I'd say you would be a-ok with oil like Mobil 1 EP 5-30 or the same in 40 weight; 5k equivalent OCI using the hour meter.......

Double check me on this as it's been a long time (2000) since I was in a Crown Vic. IIRC the addition of the oil cooler was the only mitigation tool added to deal with long idle times. Times have a changed over the last 2 decades so if I'm wrong others will let us know so and the why behind it.

It actually is a P71 Crown Vic so it has an hour meter for idle hours. There isn't one for total hours though. It also basically has a separate cooler for every component as well as running at a slightly higher idle than the civilian CV's, which has a couple benefits including alternator and waterpump output.

The boutique and extended drain oils are a suggestion I'll go with for sure, once I decide which to use. I kept going back and forth trying to decide if I should use that type of oil or just use the cheapest synthetic, considering the time frame of the OCI. It seems the extended drain oils are the consensus for my usage.

Thanks everyone for the advice.
 
I will say this, you have one of the better vehicles to handle what you’re attempting. I mean, it’s been a long time, but I used to work in a law enforcement fleet, and the crown Vic was the best (not even close). The options from GM could not handle the abuse, although the older LS1 Chevy suburbans and tahoes came close. Chrysler had nothing at the time to handle the work. You should have seen the dodge Rams and passenger cars from Chrysler try to stand up to abuse (Chrysler 300, Dodge Intrepid). They were the worst out of the big 3.

The Crown Vic is legend.
 
This is a 2017 Police Utility (Explorer) 3.7L NA, we only use Mobil 1 5W30 5,000 mile OCI, engine runs perfect, sometimes you dont even know its running its so quiet. (no bull)

Look at the Hours on this unit.
 

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Fleet average mileage estimates are 48 miles per hour.

So take that +/- a few.

150 hour OCI leads you to approximately 7200 miles. Which I think is pretty conservative assuming you’re running a full synthetic.

125 hours is approximately 6000 miles.

Assuming your numbers are correct, you should be planning on changing your oil approximately every 10-15 working days depending on your exact idling hours.

Anywhere between the 100 to 150 hour marker gives you some flexibility, as you may not be able to change it on an exact day.

I don’t change my oil on mileage anyhow. I drive a lot for work. I change it between 125 and 150 engine hours.
 
I've recently started in a new career field in which I drive 50 miles to the location, sit idling 10-12 hours, then drive 50 miles back.

I normally change the oil in my Crown Vic every 3000 miles. I remember reading somewhere that Ford recommends accounting for 25 miles per idle hour. With that being said, each day would be the equivalent of 350-400 miles. 4 work days a week makes an oil change every other week, if I were to try to stick with my normal OCI. I know the modular 4.6 is usually easy on oil, so the 3000 mile OCI isn't a necessity.

Should I factor in the idle time and just go for a 6000 mile equivalent, moving to monthly oil changes? Should I stick with actual mileage and not worry about the idle time? Or, should I just go to a time based oil change (every 3 months, etc) instead?

I'm currently running Castrol Magnatec 5w30 (local DG clearanced for $2 a quart to me) and a Fram Ultra. I've gone 2 weeks of work on it and I'm starting week 3 on Friday.
I'd definitely follow Ford's guidance. Long idle time can be hell on cams and valve train and if you e got a Ford modular engine, you've got two cams and their associated bearings, etc sitting at the highest point in the engine.
Those old Panther platform cars can last forever if they're maintained
 
We dont do the OCI by hours, its 3000 to 5000 miles, we have done oil analysis and the numbers are great, the Mobil 1 5W30 holds up. On the example I posted above, that unit may be on a 3000 mile OCI, I would have to look at service history to confirm.
 
I'd definitely follow Ford's guidance. Long idle time can be hell on cams and valve train and if you e got a Ford modular engine, you've got two cams and their associated bearings, etc sitting at the highest point in the engine.
Those old Panther platform cars can last forever if they're maintained
Would this be Ford’s guidance for an assumed heavy duty service? Oil has also improved since the book was written. Also, if the oil analysis shows satisfactory oil characteristics, why would running it longer change the wear rate? If a used lube is doing its job new and all of the additives and oil properties, such as viscosity, flash point and TBN are adequate, why would it need to be changed?

Also, are these roller cams? Is a higher ZDDP mix and shorter drains necessary because it has flat tappets or for some other reason? I mean, an appropriate add pack makes sense for low RPM and flat tappet cams, which may require a shorter interval (miles and hour), but if the OP is driving a lot of highway miles and considering idling at full operating temp is extremely low load and less likely to dilute the fuel compared to a lot of cold starts, should this be the poster child for extended intervals (beyond 3k miles, I mean)?
 
Would this be Ford’s guidance for an assumed heavy duty service? Oil has also improved since the book was written. Also, if the oil analysis shows satisfactory oil characteristics, why would running it longer change the wear rate? If a used lube is doing its job new and all of the additives and oil properties, such as viscosity, flash point and TBN are adequate, why would it need to be changed?

Also, are these roller cams? Is a higher ZDDP mix and shorter drains necessary because it has flat tappets or for some other reason? I mean, an appropriate add pack makes sense for low RPM and flat tappet cams, which may require a shorter interval (miles and hour), but if the OP is driving a lot of highway miles and considering idling at full operating temp is extremely low load and less likely to dilute the fuel compared to a lot of cold starts, should this be the poster child for extended intervals (beyond 3k miles, I mean)?
The modular uses roller followers with hydraulic lash adjusters, I've never heard of cam wear being an issue with them.
 
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