I have a 03 Crown Vic P71 which just turned over 117k. Since I bought it with 95k I have been doing regular oil changes at 4k and have been using Motorcraft semi 5w20 and Motorcraft filters. Yesterday I decided to switch it up and use Mobil 1 5w20 and a Bosch Distance Plus filter. My question is since I am now running a full synthetic oil and a higher capacity filter how much farther can I stretch out my change intervals? I was thinking maybe just go to 7k and change but I hear everything from 5k to over 12k miles. I drive a 50/50 mix of city and highway driving and I live in So. Cal so the car never sees freezing temps but will be seeing many 100 plus degree days. And sorry if this question has been asked a million times on here but it's my first post so don't bash me too hard
Crown Vic owners (OCI question)
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In my '95 Grand Marquis with about 165,000 I've been running 6-month OCIs for the last couple of years, varying from about 7-10K miles, using M1 HM 5W-30 and/or Formula Shell 5W-30. I like to change in the spring to get winter moisture out of there, and in the fall to make sure I don't have to do a change over the winter. I've cut open the filters and they look fine, either the Motorcraft, the P1, or now I'm going with the FRAM Ultra. The engine seems to be running better than ever, and the oil looks pretty clean when it comes out. Since I switched to synthetic oil consumption has decreased.
Good choice with the filter, I'm using the Bosch D+ D3410 as well.
Your OCI depends on many different factors. I would suggest going 6,000 miles and getting a UOA to see how it's been holding up, and take it from there. If you want to go one step further, you can get a virgin oil analysis from the same lab and compare the results.
Your OCI depends on many different factors. I would suggest going 6,000 miles and getting a UOA to see how it's been holding up, and take it from there. If you want to go one step further, you can get a virgin oil analysis from the same lab and compare the results.
I agree anything from 8-10K would be a reasonable OCI given that the engine is in good proper running order.
It's an ex cop car so I am sure it idled and screamed for most of it's life but it was the best running one out of the lot. You can barely feel it idling and no unusual noises. With Motorcraft it would burn a quart every 4k miles or so. I think after 6k ill try the UOA.
The police department here has a load of high mileage Crown Vics (many well over 200k) that have run nothing but Castrol dino 5w20 at 5k intervals, and that is under hard police use. I would think your Mobil 1 should do 7.5 k with relative ease, then do a UOA at 7,500 to get an idea of how far you're able to extend.
One year or 10k worked well for me with synthetic oil and a Motorcraft filter.
My 4.6 2005 CVLX [125K] miles gets 5W20 Motorcraft Full Synthetic [sometimes 5W20 Mobil 1] every 7-7500 miles which is generally 4-5 months..I probably can go longer but I am in A LOT of gridlock in Miami Beach and sometimes I let it idle here and there with the a/c on.
If I use the 5W20 Motorcraft Blend [which every once in awhile] I change it out every 4500-5K miles.
The 07 4.6 Grand Marquis gets Motorcraft 5W20 Full Synthetic every 6-8 months..Mileage is around 4K miles but is mostly stop and go and short trips.
The police agencies that do not have fleet service down here take their P71'S to Ford and change their oil every 4-5K miles using 5W20 Motorcraft Full Synthetic..Most of those cars do not see the highway.
The larger agencies that do have fleet service generally change their oil out every 3K miles using whatever bulk oil they get the best deal on..From what I hear it is generally 5W30.
If I use the 5W20 Motorcraft Blend [which every once in awhile] I change it out every 4500-5K miles.
The 07 4.6 Grand Marquis gets Motorcraft 5W20 Full Synthetic every 6-8 months..Mileage is around 4K miles but is mostly stop and go and short trips.
The police agencies that do not have fleet service down here take their P71'S to Ford and change their oil every 4-5K miles using 5W20 Motorcraft Full Synthetic..Most of those cars do not see the highway.
The larger agencies that do have fleet service generally change their oil out every 3K miles using whatever bulk oil they get the best deal on..From what I hear it is generally 5W30.
One year or 15k miles. Blackstone. Work your way back if necessary. It won't be.
Just pick a reasonable number and start there. Nothing wrong with doing something around 7k and doing a UOA to see how much farther you can push it.
Well here is an update: I have gone 5,000 miles on the M1 and Bosch filter. The car has used I believe a little over 1 quart's worth and the oil is medium tan in color. I noticed the oil is cleaner then when I used Motorcraft oil and filters at the 4k mark. I feel confident I can go 8k without an issue. We have had an unusually longer then expected summer here in SoCal (over 30 days of 100+ degree days) so the oil has taken a beating.
Did 8,900 miles on the Mobil1 and Bosch filter. However my [censored] drained it all into a bucket that had oil already in it, so no UOA this time... I figure a solid 8.5-9k on the oci isn't pushing it. Ill do a UOA next time... (used M1 5w20 and a Motorcraft filter this time)
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My 98 has about 230K on it. About a year ago I started doing between 5 and 6K oil changes. All of its life prior to this it has seen 3K intervals. Motor internals have always been spotless. The motor in the last few years or so has developed an appetite for oil. About 1 qt every 1000 miles. Even a rigorous oil changing schedule didn't prevent it from consuming it. Oh well...
Sometimes going an oil grade thicker will curb consumption.
If the body of the car is in good shape, and the rest of the car is also in good shape, save the money you would spend on synthetic and do the timing chain tensioners now. Then use your regular favorite dino oil every 5k and your engine will still make 300k no problem.
4.6L's die from two things, back timing chain tensioners, and poor coolant maint leading to electrolysis and overheating.
4.6L's die from two things, back timing chain tensioners, and poor coolant maint leading to electrolysis and overheating.
Originally Posted By: Fordiesel69
If the body of the car is in good shape, and the rest of the car is also in good shape, save the money you would spend on synthetic and do the timing chain tensioners now. Then use your regular favorite dino oil every 5k and your engine will still make 300k no problem.
4.6L's die from two things, back timing chain tensioners, and poor coolant maint leading to electrolysis and overheating.
The tensioners were replaced under the recall (it has the x... on the valve covers) and had the coolant flushed about 35k ago. It has a marginal paint job, but runs real strong and looks good from far. I did the math and changing out the synthetic oil at 9k is cheaper in the long run then doing 5k changes with dino. My father-in-law unfortunately just got the valve train rattle in his 4.6 and i'm afraid he broke a tensioner...
If the body of the car is in good shape, and the rest of the car is also in good shape, save the money you would spend on synthetic and do the timing chain tensioners now. Then use your regular favorite dino oil every 5k and your engine will still make 300k no problem.
4.6L's die from two things, back timing chain tensioners, and poor coolant maint leading to electrolysis and overheating.
The tensioners were replaced under the recall (it has the x... on the valve covers) and had the coolant flushed about 35k ago. It has a marginal paint job, but runs real strong and looks good from far. I did the math and changing out the synthetic oil at 9k is cheaper in the long run then doing 5k changes with dino. My father-in-law unfortunately just got the valve train rattle in his 4.6 and i'm afraid he broke a tensioner...
Originally Posted By: Fordiesel69
4.6L's die from two things, back timing chain tensioners, and poor coolant maint leading to electrolysis and overheating.
Speaking of overheating, have any of you guys ever had the "failsafe" engine mode kick-in whilst driving? For those of you who don't know what I speak of, here is a brief description:
When a ford engine(mine is a 98 4.6L) experiences an overheating condition(ex coolant loss), it goes into a "failsafe mode". This failsafe mode turns the V-8 into a 4 Cyl, that alternates the cylinders periodically to help manage heat build-up. So at any given time, 4 cyls act as air pumps to theoretically cool the engine. Ford says you can operate the vehicle up to 50 miles.
So...., about 2 or 3 summers ago, I'm driving home on a pleasant country road, minding my own business. I'm at least 10 miles from home. Suddenly, the steering becomes hard, the air-conditioned air caressing my skin suddenly becomes warm, voltage gauge and charge light start to complain, and in no time the temp gauge starts to climb like it's nobody's business. Oh,... and all the while under the hood I hear something getting whipped mercilessly.
So, it takes me all of one moment to realize that I shredded the serpentine belt. I had remembered too that this car has the nice failsafe mode that I briefly described above. As the temp gauge settled on the top-most extreme marker, the temp light started to blink, and then the motor started to suffer performance wise. AH!!!...it's the 4 cyl mode!! As I'm experiencing this I had to stop at two traffic lights. As one would expect acceleration and climbing back to 45 mph was difficult. So... I make it back home safely. I immediately pop the hood and start to inspect. Coolant? - gone... Serpentine belt? - some remanants remained wrapped around the water pump. Oh!!... and one more thing, the belt tensioner pulley was gone....
Belt tensioner was original
and just disintegrated. So I call up my Pops, and had him buy one for me, and in two hours time I'm back on the road again.
I really can't say enough about this really good feature that Ford utilizes. Saved me the time, expense, and inconvenience of waiting for a flatbed, that's for sure.
Any of you folks experience something similar? Do other manufactures do anything like it?
4.6L's die from two things, back timing chain tensioners, and poor coolant maint leading to electrolysis and overheating.
Speaking of overheating, have any of you guys ever had the "failsafe" engine mode kick-in whilst driving? For those of you who don't know what I speak of, here is a brief description:
When a ford engine(mine is a 98 4.6L) experiences an overheating condition(ex coolant loss), it goes into a "failsafe mode". This failsafe mode turns the V-8 into a 4 Cyl, that alternates the cylinders periodically to help manage heat build-up. So at any given time, 4 cyls act as air pumps to theoretically cool the engine. Ford says you can operate the vehicle up to 50 miles.
So...., about 2 or 3 summers ago, I'm driving home on a pleasant country road, minding my own business. I'm at least 10 miles from home. Suddenly, the steering becomes hard, the air-conditioned air caressing my skin suddenly becomes warm, voltage gauge and charge light start to complain, and in no time the temp gauge starts to climb like it's nobody's business. Oh,... and all the while under the hood I hear something getting whipped mercilessly.
So, it takes me all of one moment to realize that I shredded the serpentine belt. I had remembered too that this car has the nice failsafe mode that I briefly described above. As the temp gauge settled on the top-most extreme marker, the temp light started to blink, and then the motor started to suffer performance wise. AH!!!...it's the 4 cyl mode!! As I'm experiencing this I had to stop at two traffic lights. As one would expect acceleration and climbing back to 45 mph was difficult. So... I make it back home safely. I immediately pop the hood and start to inspect. Coolant? - gone... Serpentine belt? - some remanants remained wrapped around the water pump. Oh!!... and one more thing, the belt tensioner pulley was gone....
Belt tensioner was original
I really can't say enough about this really good feature that Ford utilizes. Saved me the time, expense, and inconvenience of waiting for a flatbed, that's for sure.
Any of you folks experience something similar? Do other manufactures do anything like it?
Originally Posted By: DinoOil
Originally Posted By: Fordiesel69
4.6L's die from two things, back timing chain tensioners, and poor coolant maint leading to electrolysis and overheating.
Speaking of overheating, have any of you guys ever had the "failsafe" engine mode kick-in whilst driving? For those of you who don't know what I speak of, here is a brief description:
When a ford engine(mine is a 98 4.6L) experiences an overheating condition(ex coolant loss), it goes into a "failsafe mode". This failsafe mode turns the V-8 into a 4 Cyl, that alternates the cylinders periodically to help manage heat build-up. So at any given time, 4 cyls act as air pumps to theoretically cool the engine. Ford says you can operate the vehicle up to 50 miles.
So...., about 2 or 3 summers ago, I'm driving home on a pleasant country road, minding my own business. I'm at least 10 miles from home. Suddenly, the steering becomes hard, the air-conditioned air caressing my skin suddenly becomes warm, voltage gauge and charge light start to complain, and in no time the temp gauge starts to climb like it's nobody's business. Oh,... and all the while under the hood I hear something getting whipped mercilessly.
So, it takes me all of one moment to realize that I shredded the serpentine belt. I had remembered too that this car has the nice failsafe mode that I briefly described above. As the temp gauge settled on the top-most extreme marker, the temp light started to blink, and then the motor started to suffer performance wise. AH!!!...it's the 4 cyl mode!! As I'm experiencing this I had to stop at two traffic lights. As one would expect acceleration and climbing back to 45 mph was difficult. So... I make it back home safely. I immediately pop the hood and start to inspect. Coolant? - gone... Serpentine belt? - some remanants remained wrapped around the water pump. Oh!!... and one more thing, the belt tensioner pulley was gone....
Belt tensioner was original
and just disintegrated. So I call up my Pops, and had him buy one for me, and in two hours time I'm back on the road again.
I really can't say enough about this really good feature that Ford utilizes. Saved me the time, expense, and inconvenience of waiting for a flatbed, that's for sure.
Any of you folks experience something similar? Do other manufactures do anything like it?
That's really a pretty cool system. Made a terrible situation very manageable for you. Which is great to hear. I have a 96 Town Car with the 4.6. Do you happen to know if my car has that capability?
Originally Posted By: Fordiesel69
4.6L's die from two things, back timing chain tensioners, and poor coolant maint leading to electrolysis and overheating.
Speaking of overheating, have any of you guys ever had the "failsafe" engine mode kick-in whilst driving? For those of you who don't know what I speak of, here is a brief description:
When a ford engine(mine is a 98 4.6L) experiences an overheating condition(ex coolant loss), it goes into a "failsafe mode". This failsafe mode turns the V-8 into a 4 Cyl, that alternates the cylinders periodically to help manage heat build-up. So at any given time, 4 cyls act as air pumps to theoretically cool the engine. Ford says you can operate the vehicle up to 50 miles.
So...., about 2 or 3 summers ago, I'm driving home on a pleasant country road, minding my own business. I'm at least 10 miles from home. Suddenly, the steering becomes hard, the air-conditioned air caressing my skin suddenly becomes warm, voltage gauge and charge light start to complain, and in no time the temp gauge starts to climb like it's nobody's business. Oh,... and all the while under the hood I hear something getting whipped mercilessly.
So, it takes me all of one moment to realize that I shredded the serpentine belt. I had remembered too that this car has the nice failsafe mode that I briefly described above. As the temp gauge settled on the top-most extreme marker, the temp light started to blink, and then the motor started to suffer performance wise. AH!!!...it's the 4 cyl mode!! As I'm experiencing this I had to stop at two traffic lights. As one would expect acceleration and climbing back to 45 mph was difficult. So... I make it back home safely. I immediately pop the hood and start to inspect. Coolant? - gone... Serpentine belt? - some remanants remained wrapped around the water pump. Oh!!... and one more thing, the belt tensioner pulley was gone....
Belt tensioner was original
I really can't say enough about this really good feature that Ford utilizes. Saved me the time, expense, and inconvenience of waiting for a flatbed, that's for sure.
Any of you folks experience something similar? Do other manufactures do anything like it?
That's really a pretty cool system. Made a terrible situation very manageable for you. Which is great to hear. I have a 96 Town Car with the 4.6. Do you happen to know if my car has that capability?
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