[harcosparky]

So I took the YJ out for our first extended ride since buying her.

When hot I noticed a drop in oil pressure at idle .... too low for my liking.

Realizing I bought this in the dead of winter and the PO just did an oil change I figured he might not have put in the correct oil. Pressure was dropping to below 10 at idle and going up to almost 30 at 2000 RPM.

So I took her home, drained all the oil and installed a fresh filter as well as some 10W30. Went for a run and things looked much better. Hot idle was now hovering at just below 20 PSI and at 2000 RPM peaking to almost 40 PSI.

I'm happier, but not static.

Ok so she is old and probably tired ...... 1995 YJ ..... 245,000 miles ...... 2.5 L

My question is this ......

Would it hurt to run say, 10W40 or even 15W40 in the 2.5L for the summer time.

I know in our Cherokees with the 4.0 I6 we run Rotella T 15W40 and they seem to love it.

Any reasons to not run the Rotella in the 2.5L.

Sure would make it easier having to only keep one type of oil on hand for the Jeeps.


Our road trip exposed some other issues, but those will be addressed with an alignment and inspection of all U-Joints.

 

[kik]

The oil pressure gauges aren't that accurate on YJ's due to either the sending unit, gauge, or both. If you're going by the stock gauge I wouldn't be concerned about it. If you want to know exactly what your true oil pressure is you have to connect a quality mechanical gauge.

 

[harcosparky]

I realize they are not accurate, but even so they do tell a story.

At temp, while idling the stock gauge showed

Before New Oil - below 10 PSI ( went up to 30 PSI at 2K RPM )

After New Oil - below 20 PSI ( went up to almost 40 PSI at 2K RPM )

So even though they are not accurate, it did indicate to me that the oil change had in fact made a difference. Now just to be clear ..... all reading were take while the motor was in fact at temp ..... 210 degrees indicated on temp gauge and after 45 minutes of run time. Here again the stock temp gauge may not be accurate but I know how to tell when a few thermostat openings and closing have occurred by watching that gauge.

Yeah the mechanical gauges are on the list.



Having said all of that, my one question remains unanswered ........

Is it OK to run Rotella T 15W40 in the 2.5l motor?

If not, why not, exactly?

 

[Ov yj]

Yep its fine, I run Rotella in everything.

 

[Nanookofthenorth]

How the hell did you get 245k on the 4cyl. That's gotta be a record.

 

[harcosparky]

How the hell did you get 245k on the 4cyl. That's gotta be a record.

I am not the original owner, however the more I dig into this vehicle to take care of age related issues ( soft parts gone bad ) I am realizing that this YJ was extremely well taken care of for the most part.

I am the third owner, the first owned it for 18 years, the second had it for 2 years. The last owner is the one who messed up the things that are messed up on it ..... neglected some routine maintenance, failed attempt at a lift, and other things that inexperienced " I know what I am doing 'cause I seen it on YouTube " owners do to their Jeeps.

I hope to bring it back to it's original glory as much as possible and push that motor a little farther.