2002 Merc Mountaineer 4.6 is due for an oil change in about 700 miles. Is it worth going with synthetic? I've been using regular pennzoil 5w20 since I got it last summer.

 

they will run forever on regular oil and 5000 mile oil changes. there is only an advantage to synthetic if you drive several thousand miles in a couple months and want to try to go to extended oil changes...example--- if i drove 5000 miles per month, i would not use standard oil and changed it every 30 days.. i would go with synthetic and change every 60 days.

 

Depends on how many miles on the vehicle and how long you plan to drive it [miles]. I am currently only running synthetic in my diesel truck for soot control on the turbo veins.

 

Thats what I was thinking. I change the oil pretty regular 3-4k miles, usually only put 6-10k miles on a year.

My diesels I've been running regular rotella 15-40 on 5k/yearly (which ever comes first)

 

Your engine will be cleaner internally, run better, give better economy (by 2 to 5 mpg), extend the miles between changes, last longer before an overhaul is needed and be happier with a full synthetic oil. I have been running Mobil 1 in my Mark VIII since buying it used with 85,000 miles and it runs flawlessly at 198,000 now and it has not been babied. Inside of the valve covers appears nearly new and clean. AMS oil says that if you use AMS oil filters you can change the filter at about 7,500 miles and the oil and filter at 15,000 miles.

 

---your motor will not run better on synthetic
--you will not get 5 mpg better milage
--if you run 6000 miles per year and change the oil at 15k miles, your hurting the motor not helping.
---again, if you drive 6,000 miles a month and want to change oil every 60 days, that makes sence.. if you drive 6000 miles a year, change every 6 -8 months and use std oil.

 

I'm with Steve. I did switch my 4.6 van (an '02 E150, so same engine as yours except iron block) to full syn at around 60k miles. The motor runs no better nor worse. I do not get even ONE more mpg--the statement of 2-5 mpg more is completely unbelievable and unfounded.

I switched to syn because I got 24 quarts (QS Torquepower 5W20) for a buck each, and my van does like it. I feel no guilt running the oil out to 7000-7500 miles, whereas I used to do 4-5k changes on Motorcraft syn blend.

I have no more of the syn oil stashed, so I will either buy full syn if I can get it on sale or if not, go back to Motorcraft syn blend.

Amsoil marketing seems to convince a lot of folks that their products are magical--they are not, and I don't believe in 15k mile changes unless you drive 5k miles a month or something. Their filters are good, made by Champion I think, same as Mobil 1 filters. For a lot less money, Motorcraft filters are great, as are Purolator Pure Ones.

George

 

I can only tell you for certain what I have experienced.
I first started using a cheapo synthetic from Discount Auto Parts about 1991 in my son's 3.0 Probe and gained an average of about 4 mpg I then used it in a 305 Firebird and got the same results. I then bought a Mark VIII and after using the dino oil for the first 3000 miles switched to the same DAP synthetic oil and the combined city/highway mpg gain was about 5 mpg, I've been using Mobil 1 ever since in all of our vehicles with great results. My local Ford dealer does oil and filter changes for $10.00 and I did change to dino oil for one oil change and at less than 3000 miles the oil looked dirty, which I attribute to ash which normally occurs in gas engines but I have never had that color oil before using synthetic oil and my mpg has gone down. However my combined city/highway mpg is 20/22 and all highway was 28 mpg recently and thats with 198,000 miles on the clock. Also there is less than 1 pint consumed between changes using 5W20 wt.
I'm happy with my Mobil 1 and intend to continue using it. I hope you have as good results using your dino oil.

 

I wouldn't say that I've noticed a difference in the appearance at my change intervals of the Mobil 1 synthetic oil that I now use versus the dino oil that I've used in the past, but I would say that the engines seem to crank over better in the winter with the synthetic and my fuel economy is slightly better with synthetic. On my 2004 Mountaineer V8 that I currently have, and the 2000 Mountaineer V8 that was its predecessor, my highway fuel economy was consistently higher than EPA ratings and what's listed at fueleconomy.gov. Included in my "higher than EPA ratings" travels are fully loaded 600 mile trips during the summer with 2 adults, 2 kids, 2 weeks worth of luggage, and 2 mountain bikes hanging off the rear. The trips were not all in one compass heading so a tail wind the entire way is not really a factor. I've experienced similar results on short trips with 4 adults and 4 bikes on the back. All these summer trips also included air conditioning being used.

My real test will be with my car. I've owned it since new and the recommendation is to run it for 15k miles before switching from dino oil to synthetic. It's taken me 3 years to get to 11,500 miles though so I won't have results for awhile. I can say the ONLY time I've yielded the EPA rated fuel economy was the 100 mile drive home from the dealership, trying hard to keep it below 4500 rpms for the break-in period. Every highway trip since then has been 1-2 mpg lower than EPA rating.

My city driving is too inconsistent for me to attempt to use that for any sort of comparisons.

I should also add that on the Mountaineers I changed the oil (regardless of chemistry) based on what the computer suggests since I don't know what it uses for an algorithm (mileage or actual chemical/physical analysis). On my car I will likely go off the recommended 3750 mile interval since that ends up being about an 8 month interval. My wife's 2010 MKZ has a recommended 7500 mile interval using synthetic. Neither of the cars mention a time interval (3 months, 6 months, etc.).

-Rod

 

I have tracked mileage on my van since it was brand new in a spreadsheet and it now has 81k miles on it.

At 60k miles, before I switched to synthetic oil, overall mileage was 16.32 mpg. That is every tank of gas and every single mile for all that time. And that was entirely Motorcraft 5W20 syn blend. I'm guessing that this oil may be superior to many plain old dino oils for mileage.

At 81k now, overall mileage is 16.18 mpg, meaning that overall averaqe mileage has been lower over the last 20k miles--during which I have used full syn oil. Part of this may be reformulated gas, but it's clear that syn is not giving me a mileage increase that is measurable.

I'm guessing your mileage readings have not been over the long term, but possibly single tank or single trip readings, which are usually misleading.

Trip mileage has been as high as 17.5-18.5 mpg, both before and after the switch to full synthetic. Same make, size, and brand of tires as OEM (Michelin LTX M/S), no other changes in equipment or driving habits.

Being in Michigan, I do like the idea of full syn better in the cold winter months, and I do have to say that oil consumption seems to be a bit better on full syn (maybe 1/3 quart down over 6k miles). So if I can find full syn on sale for $3 per quart or something I'll probably continue using it in the van. This has been my first use of full syn (I had a lifetime habit of 3-4k changes, since 1970, and decided to move to full syn and stretch changes out a bit when I got my buck a quart stuff.)

I don't believe that the color of oil tells you very much about its condition. A darker color might indicate that it's cleaning better, actually.

George

 

I must admit that I am not nearly as methodical as you in keeping track of my mileage but, I calculate my mileage at every tankfull and only use the onboard reaqdings as a guide, not gospel.
My son's 04 Mountaineer normally gives him about 17 mpg city/highway on his daily 66 mile commute and a few short errands. I used his Mounti for a trip of about 750 miles and had a peak of 24.2 mpg in one segment and an overall of just under 22 mpg for the trip. My driving style is a good bit different than his as I use cruise as often as possible.
The color of the oil between changes is only an indicator of what is going on in the engine and to me a clean engine is a happy engine. The best way of knowing the condition of any engine is to send a sample of the oil removed from the engine out for an analysis of it's condition. I have not done this as yet.
With the mandated use of alcohol in our gas I have found that my mpg is down a bit and I wonder if it really helps the environment. That could be a whole 'nother thread though.

 

I use full synthetics, but I do also run 30K per year or more. I change my oil and filter at ~15K intervals. But I do a lot of driving and the type of driving I do supports the intervals. If you drive 10K per year or less, synthetic probably won't help you. For one, you don't want to leave any accumulated gunk in the engine for very long. For me, the oil changes are still at least 2 per year. But for yours, the acids and gunk would sit i the engine for over a year. Short infrequent trips will not clear it out.

 

My vehicles all use Mobil 1 oil. On the two that get 10-12,000 miles a year I change it
every 5000 miles. On the ones that get only 2-3,000 miles a year, I chage it once a year. All of them are in good shape and run well, even the one that has 140,000+ miles
on it.

 

140,000 is practically new. You are not going to notice whether regular or synthetic wear better within that period. When you roll past 200k, then the engine starts to talk.

 

after 200k you might have problems with water lines, water pump, gaskets, electronics, etc.... you should not have OIL related problems till 300k or later... with good dyno oil or synthetic.