What oil at 190k miles 4.0L 6cyl?

[Joe E]

Just got a nice '95 Explorer. Great condition but I'd like to change the oil and the book says 5W-30 or 10W-30. But this engine has over 190k miles. Runs good. No smoke. No leaks. Should I stick with those or maybe 10W-40 or straight 30 or 40 weight?
Joe in NJ

 

[97BlackX5.0]

i would stick with whatever you have been using... no reasont to change it now.... if it starts using oil a little or leaking you can try the heavier stuff..... i use 5w30 synthetic in my 97 v8 and it has 127k on it.... no reason to change

 

[Joe E]

OK, thanks. Was just having the u-joints changed by a mechanic friend of mine tonight which completely eliminated a bad vibration upon accelleration. I asked him the same question and he said the same thing as you. I notice you use the synthetic. What is the advantage of that?

 

[Dakota1358]

From what I hear synthetics have a way of finding leaks.So I'd stick with just regular oil if you have no leaks now.Of course thats just personal opinion

 

[JDraper]

I'd run 10w30 conventional. Synth can have a nasty habit of "finding" leaks in older motors. The synth cleans out the motors, removing the gunk that keeps leaks from happening.

 

[Joe E]

OK, I'm convinced. I'm sticking with the 10W30. I didn't know that about the synthetics--that they "clean out" the engine. Yeah, that will find leaks. I remember an old timer told me that a long , long time ago about engines with high mileage. Not synthetic oil in his case, don't think it was invented yet. He meant other products that clean. I was messing with an old sport car at the time and that's exactly what he warned me against.

 

[97BlackX5.0]

yeah synthetic particles are smaller and will clean out areas and find leaks.... there are advantages and disadvantages to synthetic oil.... ask 100 people and you will get 100 different answers... some love it some hate it.... some dont know enough about it.... i have been running it for about 50k miles now and have not had any leaks and have had good results with it so im sticking with it.

Some advantages.
Biggest in my book is the way the oil does not get thicker in the winter like regular "dino" oil....and results in faster pumping during cold starts and faster cranking....
Most people report a increase in mileage
Will not break down in high temperatures
Can be used for extended drain intervals with special care taken for filters
Reduced engine wear by providing superior lubrication on cold starts.


Some disadvantages

Its fairly expensive compared to regular dino oil.... mobil 1 is about 20 bucks for 5 quarts whereas conventional oil can be had for about a buck a quart depending on your brand.

It will leak through an engine that already has leaks faster than conventional

It can find leaks that conventional oil would not leak through normally because of its smaller particles


So if you plan on keeping your vehicle till it goes to the great junkyard in the sky i'd use synthetic....unless its leaking conventional oil already ... otherwise the short term benefits are a little better mileage ... and while we can all use that i dont know if it would offset the higher cost of synthetic enough to make it worth it.....