This article is from the Chrysler-Plymouth-Dodge FAQ, by Dr. David Zatz with numerous contributions by others.
On February 7, 1995, a Chrysler engineer said 5W30 was best for
2.0, 2.2, and 2.5 liter non-turbo engines, for winter or
year-round in climates such as that of New Jersey.
All dealers I surveyed incorrectly recommended and used 10W30!
- In 1993 and 1998 Chrysler said 5W30 was best for all its cars.
- Dan Stern says synthetic 10W30 is better than natural 5W30.
- The benefits of 5W30 or synthetics seem greatest in cold
weather when oil is most viscous (before the engine warms).
- Even GM recommends 5W30 on their Vortec V8s.
Use Energy Conserving II and SH grades where possible.
For my car, recommended oil changes are at 6 months / 7,500
miles. I change it at 6 months or 6,000 miles. GM says many owners
do not need to change oil until 10,000 miles! If you are concerned,
use synthetic and change at 6,000.
** CHECK YOUR MANUAL **. Dealers often suggest things like changing
your antifreeze every three months to get easy money. If
you exceed Chrysler's recommendations, do the easy work yourself.
PS> Overheating after a an antifreeze change/radiator flushing
means your mechanic didn't purge the system correctly.
Be careful to thoroughly purge the system of air bubbles -
or invest in head gaskets. This is VERY important.
5W30 is generally recommended for the 2.0 and 2.4 liter engines, too.