Rotella sounds like a good choice. They mention better flowability during cold temperatures, wonder what they add different to accomplish that considering it's not a synthetic.
Features/Benefits
• Exceeds requirements of today’s high-performance, low-emission diesel and gasoline engines while providing excellent performance in older engines allowing operator use of one oil for many engines
• Product is warranted against defect and meets virtually all US and European equipment manufacturer’s warranty requirements minimizing operators risk
• Outstanding protection against engine wear due to soot - helps extend engine life
• Exceptional protection and durability demonstrated in control of valve train wear - maximizes engine life
• Unique additive chemistry minimizes viscosity loss due to shear and viscosity thickening due to soot – this helps the oil stay in grade for better engine operation
• Exceptional low-temperature flow properties helps speed cold starts
• Reduced fuel consumption compared to single-grade oils can help lower operating costs
• Improved deposit and oil consumption control, and better oxidation stability -- for the operator this could mean lower oil cost and extended overhaul life expectancy and increased flexibility
Leaks: If you have leaks already, a more flowable oil, like a synthetic, may leak more. You should be okay.
Cleaning the engine: If you are anticipating the engine is somewhat dirty and will be cleaned heavily by the new oil, then you might want to consider an oil / filter change at 2000 miles, then 3000 miles for the first couple of oil changes. Mobil 1 recommends this "
here" when when changing to synthetic. You will find that site interesting and this
one (tests on Major brands) interesting as well.
Filters: The Ford FL-1A filter is economical (at Wal-Mart in US), used by many (not me per say), is large sized, and made by Purolator (string attached to cartridge is the sign). The Mopar equivalent to that filter is also the same size although not listed for your Jeep. I use that Mopar filter. It's 5" long versus 3.5" standard, 3.5"+ diameter. For a more premium filter I would go to a Fram Tough Guard 8A high efficiency filter with silicone (orange) versus nitrile (black) anti drainback valve.
Oil choice: As for oil choice, I would consider the following:
- run diesel motor oil for 500 miles and then change oil and filter. Motor oils for diesel engines are high in detergents. Perhaps your Rotella will do the equivalent.
or
- run synthetic oil for 1000 miles and then change oil and filter. (You may want to cut your filter apart to see what it looks like inside, lay out the filter media and test for metals with a magnet. That should give you some degree of comfort with your engine. Alternately get an oil analysis done.)
or
- just run a major brand 10W-30 oil (whatever is on sale is my decision maker) meeting API SM standard and Chrysler MS6395 standard plus an oversize filter and not worry, be happy.
In the US, the Mopar filters are made by Purolator and in Canada by Wix. Both have the bypass valve at the base (versus the cap) which I like. I'm attaching a picture of a Fram TG-8A which I cut apart.
