4.0 OHV Just Began Using Oil.

[BamakoJon]

I've got a '99 explorer with the 4.0 OHV engine with 252,000 miles. Until I checked the oil two days ago, I've never seen it use any oil. I changed the oil at 250,000, and most of the miles since have been highway. Is there anything that I can do to help it? It's not bad, but if there's anything I can do to keep the 'ole girl kickin' longer I'd like to know.

Should I just count myself lucky to have gotten so far without this happening or what? Is there some kind of additive that can help mitigate the issue? Thanks!

 

[Mbrooks420]

How much oil did you have to add?

 

[96eb96]

I've got a '99 explorer with the 4.0 OHV engine with 252,000 miles. Until I checked the oil two days ago, I've never seen it use any oil. I changed the oil at 250,000, and most of the miles since have been highway. Is there anything that I can do to help it? It's not bad, but if there's anything I can do to keep the 'ole girl kickin' longer I'd like to know.

Should I just count myself lucky to have gotten so far without this happening or what? Is there some kind of additive that can help mitigate the issue? Thanks!

Any external leaks? Valve covers? Crank Seal?
Try a high mileage oil. You could probably goto a 10W30 with no problem on this motor, esp in Texas. I know this motor has a 5W20 Prohibition.

 

[BamakoJon]

I maybe had to add a quart, probably less. It was in a big jug so it was harder to tell exactly how much.

I've never noticed any external leaks or oil. Just general greasiness in some places, but nothing that ever made me think something was up. I've been running 10W40, as that's what had been used before it got it. Right now it's got Mobile1 full synthetic.

 

[974X4BLACKSPORT]

Install new valve stem oil seals. On older high mileage engines, these seals get hard, crack, or completely break and fall off the guide, letting lots of oil go by the valve stem and either down into the intake port (then combustion chamber), or out the exhaust.

 

[fast_dave]

@BamakoJon

Just offering up: Throw a clean sheet of cardboard under your Ex's engine area and watch it a few days - perhaps a new leak has sprung up? The fresh cardboard makes this a lot easier to spot.

On your 252,000 mile OHV Ex, I'd be looking at these areas prone to leak on this particular engine:

* the rear/firewall areas of BOTH valve covers (rear most bottom valve cover bolt on both sides is notorious to loosen up)

* rear engine seal

* and once you approach & break 200,000 miles - the area around the "oil filter adapter" (where you mount the oil filter - initially you'll see oil build up on the engine block around the adapter, then on the adapter body, and eventually oil will drip down the side of the filter).

Link to write-up: How to: - Replace Gaskets On The 4.0 OHV Oil Filter Adapter / Mount

In closing, just asking: How fast are you recently driving on those wide open highways in TX? Are you going over 70 - 75 mph for any distance?

 

[koda2000]

When's the last time you put a new PCV valve in it?

 

[rasouth]

If you don't see any external oil leaks it may be an internal leak, maybe into piston. Any smoke coming from tail pipe? Compression check?