weird oil change questio...

Changed the oil (Mobil 1) 500 miles ago, 10/30, want to drop and save it and refill with heavier oil for the summer. Then throw it back in when the weather cools off.

Is this feasible?!?

Thanks,

sv

?!?

Do you have a lot of engine wear, or is there a problem?

I don't see that 10W30 will be a problem for summer weight, unless you've got a leak or some other issue to handle first. Most new cars are spec'd for 5W30 year-round, or maybe lighter (isn't there a 5W20 out there somewhere, and something getting close to a "0"?)

There also isn't a lot of point to saving oil and pouring it back in later - I've always considered drained oil as "contaminated." Even if the engine is spanking clean, it's going to pick up some crud as it is drained.

I'm sure you could filter it and reuse it if you really want to, but why? If you change oil weights by seasons, the best thing to do is keep track of what season your oil is going to spend the most time working in.

I run 10W40 year-round here in the Bay Area, with no problems. Granted, we don't really have a "winter" - but I drive cross-country quite a bit, and 10W40 is my standard oil. No problems here...

5-90

The whole point of having a 10w30 oil is that it has modifiers that allow it to work well at multiple temperatures. Back when I was a kid, single weight oil was common and people switched to a thinner oil in the cold winters, but with multigrade oils that went away. Especially with synthetic oils, there is no reason to swap. Pick a viscosity and don't worry. Personally, I would run 10w30 in most XJ's. 5w30 would probably be fine, but running hot lugging on the trail leads me to want a thicker oil.

I've been running 10w30 Mobil-1 in my 98 for the past 274,000mi...all year. Both TJ's run the same thing, same filters.

Oil pressure maxes at 43lbs, idles mid day sometimes about 15lbs.

Not much different since new, M1 last 100k, runs better than new now.

Idea popped into my head reading an oil weight thread here lately, just a thought...

Never ran above a 30 weight, curious to see what the gauge says, also heard though that if theres' no appreciable bearing wear, oil pump has to work harder to push heaver oil, even after warm-up. Myth?!?

Thanks...

sv

mikeny59 said:

Oil pressure maxes at 43lbs, idles mid day sometimes about 15lbs.

Not much different since new, M1 last 100k, runs better than new now.

Idea popped into my head reading an oil weight thread here lately, just a thought...

Never ran above a 30 weight, curious to see what the gauge says, also heard though that if theres' no appreciable bearing wear, oil pump has to work harder to push heaver oil, even after warm-up. Myth?!?

Thanks...

sv

Click to expand...

I wouldn't bother with it unless you are getting a lot of lifter tapping noise and have some oil leaks. I ran 20w 50 in my 89 XJ w/ the 4 liter in the summer though because it had some loud lifters and it leaked a little oil from the rear main and a few other spots. The heavier weight oil made it a little quiter and it slowed the oil leaks down.

I really didn't want to tear into the motor and it the 20w 50 was a good band-aid. The motor was getting up there in miles when I started, 180,000 or so. My little sister is still trying to kill it but can't.

My 98 runs just fine on 10w 30 year round. Either way as long as you have oil in your motor your going to be fine. The 4.0 is a beast that keeps on ticking.

10w30 is what I run all year round in my jeep.. No problems.

As for the heaver weight oil, your pump will have to work harder to pump the thicker stuff so you'll actually lose some HP/MPG. Might be miniscule losses, but still not worth changing out. Esp. with synthetic.

mikeny59 said:

Oil pressure maxes at 43lbs, idles mid day sometimes about 15lbs.

Click to expand...

That's within specs. The FSM calls for a minimum of 13 psi at 650 RPM idle, and 37 to 75 psi above 1600 RPM.