EfJuanFiddy

i havent decided on brand but searching i found this (to answer the switching question) id still like to find more info.....
http://www.mobiloil.com/USA-English/...o_Mobil_1.aspx

McLubben

What qualifies as a "high-mileage" engine. I am contemplating switching to synthetic on my next oil change and have been running conventional 5-20 and 5-30 oils every 3k miles since I have owned the truck (1 year now). Would I be perfectly fine making the switch to synthetic and riding it out for the 5-7k or should I make the switch and change it at earlier intervals for the first few runs?

hm12460

The only way to tell for sure is to take a sample and send it in for a used oil analysis. You guy's changing out your synthetic oil every 5,000 miles or so are throwing money away. Today's oils have a much better tbn retention than even a decade ago. On a further note, it is tough to beat Motorcraft oil and filters. It is packaged for Ford by Conoco, and is a very good product. If you follow the manufacture's recommendation, you can't go wrong, as pertaining to brand used, interval, and viscosity.

EfJuanFiddy

in the event the previous owner used regular oil, is it safe for me to just start putting in full synthetic ??

Brandmaner

I'm with same question as the poster before me i like synthetics more

dereku

I did on all my vehicles i ever owned with no issues. Bought my wifes explorer with 40k and second i got it i put in full synthetics. Now had 82k and no oil related issues.

EfJuanFiddy

may i ask what oil you are using?? ive been looking at mobil and castrol ...

dereku

Always use penzoil platinum in my gas engines.

Decent price, good brand history, and it comes out pretty clean. All the oil testing rates it fairly high too.

Btw shell rotella T5 for my diesel engines.

EfJuanFiddy

Ok cool! My dad uses shell rotella for his as well

dereku

Really isnt anything else to put in a diesel thats worth a crap compared to it. But do your own homework on oils and see what sounds good to you.