AmericanMuscle4.6GT

For a higher mileage (87k) 2005 Mustang GT, what should my oil change interval be for full synthetic?

3k? 5k? 7k?

My research suggests that Ford recommends 7500 for 2007 and newer vehicles. What has been your experience?

flash_xx

I do 3000 miles using motorcraft semi-synthetic 5w20. Some manufacturers claim you can go much longer if you use their filters and oil but honestly the Motorcraft oil is pretty good. I track my car all the time and compression is high and even on all 8 cylinders with 50k miles on the odometer. If you don't race I guess you could get away with 5k on full synthetic and a good filter. I wouldn't go past that.

SCCAGT

All manufacturers have stated higher than what is considered normal for many years. Obviously, you can use their 7500mi recommendation, but, how long due you want to run your car trouble free is probably the question you want to ask yourself. There is a reason why oil gets changed earlier than that recommendation. Junk has a tendency to accumulate in certain spots if left unchecked. Whereas, if it were changed out sooner it wont. Its cheap insurance by far.

I have a lady with an 06 Fusion 4cyl that comes in to the shop RELIGIOUSLY at 3000mi. Every oil change looks nice and clean. She could easily go longer if she so desired. I have told her that. Her response is what I always say to others anyway, and I didn't coach it out of her. She said, "Well these 3000mi oil changes are why it looks good, and will continue to look good." By the way, she hit 190,000mi last month with only brakes, tires, and a battery change since she bought it. Pretty good track record with that car.

Its that phrase "an ounce of protection......"

With all that said, Amsoil touts 25,000mi oils changes. I am a firm believer and user of Amsoil. But I don't feel comfortable going that long UNLESS the double filter system they sell is used. And even then, it is still dependant upon the vehicle and how its used.

Goldenpony

I do 5K with full synthetic

algregory

I use Amsoil 0w20 and 6 ounces Tufoil in my '05 GT with 75k on the engine. The operative question is do you drive it a lot and do you get quite a few highway miles on it? Short trips, change more often, lots of highway, change less often with Amsoil. If you do a lot of short distance driving, changing once a year not a bad idea at all.

I use the Amsoil filter, and I've been using "Tufoil" for near 20 years, likely more. I had a BMW set up for road racing and the machinist that built the engine recommended Tufoil. He was renown in the BMW world.

movielover40

I live close to work so I do a lot of short drives so I change twice a year with Mobil 1 and Mobil 1 filter.

JimC

First, if you want to know how your oil is doing get a sample tested at an oil change. I use Blackstone Labs. They have no vested interest in selling me more oil, like the oil change places that say "change it at 3,000 miles regardless of what the manufacturer says." Remember that they are in the business of selling you more product.

And as far as the woman with the Fusion changing every 3,000 miles and the drops look clean. My 2006 V6 Mustang had 203,000 miles on it, was running nitrous for two race seasons, then at 90,000 I pulled the nitrous and put the Xcharger Xtreme on it. The car made many 1/4 mile passes on that set up. I started out following Ford's recommendation at that time for 5,000 miles. After testing with Blackstone I was going 8,000 miles and the tests were saying to stretch it more. No problems in 203,000 miles and the new owner has been keeping up the 8-9,000 mile oil changes, and now has 220,000 miles on it, and no problems.

jz

I also use Blackstone. They provide great detailed information, not guess work and assumptions. There's really no logic in changing oil at 3,000 miles any more. We have long since passed that point of 3,000 mile oil changes.

I have been running synthetic for years, and never change at less than 5,000 on any of my vehicles. Depending on the vehicle I will go to 10,000 miles on an oil change.

It you want the best possible answer to youf question, go to Blackstone's website and request a free UOA kit. Pull the sample with the engine warm (20 minute drive), and from the middle of the quantity drained. Spend $28, and you'll quickly have an answer based off your car/driving style/oil.

Norm Peterson

Depends on your usage - Ford also defines a few circumstances that can define "severe service", which specifically invokes a 5000 mile OCI recommendation.


Since I do road course track days a few times a year in my 2008 GT, I don't let my oil go nearly as far as 5000 miles in between changes and wouldn't regardless of oil brand or type. If I was a drag racer instead, I still wouldn't go a whole season without at least one mid-season change no matter how few miles were added to the odometer.


Norm

Goldenpony

I use Pennzoil Ultra 5W20. My '06 GT has 142K miles on it and doesn't use a drop between 5K mile changes.