I have my 2001 F150 with the 4.2 and I use Castrol Edge Syntetic oil. I was told that I can go up to 8,000 miles before changing it. Any truth behind this?? Thanks guys.

 

What really has a lot to do with how long you can go is the filter. If you are using say a Fram Extra Guard or Puralator Classic filter I would stick to around 5,000 miles. But if you are using a high capacity, high performance filter like K&N, Mobil 1, Amsoil, etc. I would say you could definitely go 7,500 or so.

I know guys that use synthetic oil at 5,000 miles will change the oil filter but not the oil and will top off what oil was loss with the filter change, and then at 10,000 miles the change the oil and oil filter and then start the process over. They have been doing that for years with no problems, however I don't think I would do that.

 

better to be safe than sorry imo, i do every 5k on the truck and every 3k on the car both full synth royal purp with k&n filter with lucas synth oil additive and if either sit for more than 60 days ill change just the oil before running.. just what i do.. 8000 miles seems ridiculous to me.. especially when im comparing in kms

 

I have a personal thinking on this.

I agree that you could go the extra miles on syntetic oil. Thats what it is designed for.

However the carbon which makes the oil black is still there. I use dyno oil and change it often, every 3000 miles, that way there is always fresh oil in the crankcase. I have 190,000 on my truck with no internal engine problems.

 

Problem is that almost all "synthetic" oil is group III dino oil. Amsoil, Royal Purple, and Redline may be the only exceptions. I don't know if the real synthetic is actually better.

 

You will get many opinions on this, too many.

Most real evidence would say 8K on synthetic would be just fine, assuming normal driving.

The people changing every 5K are just wasting money, but that's their right. Certainly better than following some of the current manufacturer's recommendations.

 

I use Mobil 1 EP and a Mobil 1 filter, and I go 10k between changes.

 

Im about change my oil with royal purple and a k&n filter. Supposedly with the royal purple you can go 20k with just a filter change at 10k. But I dont know if I would want to try that.

 

Better off without the Fram. Though, I'm sure the extra guard has to be at least 0.1% better than their regular filters.

 

Oh believe me I don't use Fram, or recommend them for that matter. Just using them as an example of a lesser, or standard oil filter. I only use Mobil 1 or K&N and occasionally STP when they are on sale

 

i use castrol high mileage, im sure my modular is different than the pushrod motor, but i could probably squeeze another 2k out of it, (i run 3k intervals). with the motorcraft Fl-820s filter.

 

Thanks for all the input and advice fellas. I'm at like 3,500 miles since I last changed my oil and I think I'll change it at 5k and for the oil filter I use K&N. Now the joy of changing the oil in my 2004 F250...fml lol

 

Amsoil is GUARANTEED 25,000 miles. I've been using it for years, around 75k in my 1987 blazer and close to 12k in my f150 right now. We've had truckers report upwards of 200k with no issues.

Amsoil is the only true synthetic, built from the ground up, while other "synthetics" start with a petroleum base.

Just sayin, if you wanna do it right, use the best. If you want more info feel free to ask or PM me. (O, and I can get it for you at a discounted rate)

 

I used to be an Amsoil dealer - and let me tell you, I would not try to run it 25k without a bypass filtration system and an analysis program.

Not all Amsoil is a true synthetic any more. I believe the only one that is still a pure PAO synthetic is the Signature. The base stocks are just getting too expensive.

To the OP: If you are going to be changing your oil every 5k, there's no reason to use anything other than the Motorcraft synthetic blend and Motorcraft filter.