I did my own oil service at 1000K today and installed Mobil 1 5w/20.

Do you let yours go the full 10,000 for a oil service?

I was thinking 5k is a much better mileage.

Mark

 

I didn't for the first change, but thereafter I always have. Coming up on 130k mi now.

 

Depends on what you want from the FEH. Are you in it for the long haul or will you trade it or replace it in 3-7 years?

 

I'm going to have this truck for at least 10 years, 150,000. Unless it blows up.

 

Next question: Are you interested in modifying the lubrication system in your FEH for longer life?

If the answer above is no then shift to a full synthetic and change oil at a comfortable interval for you (I'll elaborate.) Shift now.

Note that there are very few full synthetic engine oils on the market although the word is used across the market. The friction inside the engine is driven by the bulk oil, not an additive package.

There are two reasons to change oil: depletion of the additive package (ie the chemistry) & saturation of the ability of the oil to hold ash (eg wear products) in suspension.

So what's a comfortable interval? I changed the oil (yeah Mobil One) & filter on my Suburban every 3k miles until I installed a bypass filter later in life (its at 384k miles & gets 5k per quart nowadays). I installed an electric prelube oil pump at about 40k miles.

That's probably a bit frequent today. Your 5k miles mark is good in my observation and may itself be a bit frequent. Buy the best filter with the smallest particle size you can find.

Let me know if you're interested in some changes to your FEH's oil system. I have some thoughts.