Higher weights = for hotter weather.
Use lower weights in winter, higher in summer.

I've been told (but haven't researched it myself), that manufacturers are recommending 5w-20 as part of some energy conservation program... lower viscosity oil in millions of vehicles = substantial reduction in fuel/oil consumption??

From the manual:
"Engine Oil Selection
For best performance and maximum protection for all
engines under all types of operating conditions, the
manufacturer recommends engine oils that are API Certified
and meet the requirements of DaimlerChrysler
Material Standard MS-6395."

There are many oils that will meet the two certs required my Chrysler, ( API amd MS-6395) 5w20 is a general use nut if you are going to run in hotter than normal you will not ruin your warranty by running a 5w30 that meets the requiremnets. Here are a few examples from AmsOil Specs, Just check the specs for what ever brand you desire.
AMSOIL Signature Series 0W-30 Synthetic Motor Oil is recommended for use in gasoline engines, diesel engines (API CF, ACEA B5) •Meets Daimler Chrysler MS-6395N
AMSOIL Synthetic 0W-20 Motor Oil is recommended for Honda, Acura, DaimlerChrysler, Toyota, Ford and all other applications where SAE 0W-20 or 5W-20 is required with the following specifications:

* API SM/CF, SL, SJ. . .
* ILSAC GF-4, 3. . .
* ACEA A1/B1
* Ford WSS-M2C930-A
* DaimlerChrysler MS-6395N

AMSOIL Synthetic 5W-30 Motor Oil is recommended for gasoline engines, diesel engines (API CF, ACEA B5) and other applications requiring any of the listed worldwide specifications:

* API SM/CF, SL, SJ ...
* ILSAC GF-4, 3 ...
* ACEA A5/B5-04
* JASO VTW
* GM 4718M, 6094M
* Ford WSS M2C929-A
* Daimler Chrysler MS-6395N
* VW 503.00

But the 5w40 oils meet API but also meet a stricter DaimlerChrysler MS-10725
That is the same requirement that
# BMW LL-04
# Mercedes Benz 229.31, 229.51
# Porsche
# Saab
# Volvo
# Volkswagen 502.00, 505.00, 505.01
All require.
Run it it will not hurt your engine, They would have to send a sample to a lab and any lab would tell them that the oil would meet the requirements.

Zak,
My friend in Queensland wrote:

Never seen Amsoil or Royal Purple but most Repco stores, Autobarns and Supercheap stores have Mobil One.
I used Castrol Edge in my Landie, 5W30. Good stuff.
Trev.

Cheers

This is the same 3.8 liter that's been around forever. I'm sure if you go back a few years that you'll find a 5w30 and maybe even a 10w30 recommendation for this engine in previous generation vehicles.

The recent 5w20 oil recommendation for many engines is an EPA mandate I believe. So I wouldn't hesitate to run 5w30 if that's all that is available.

That being said, the guys over at www.bobistheoilguy.com seem to currently believe that due to the very high quality of the current 5w20 and 0w20 oils that they out perform the 5w30 oils. My understanding is that the smaller the viscosity spread, generally the better the oil.

I've done a little reading on this lately. The concensus is that modern vehichles have much superior cooling systems that hold the engine temps in a very tight range for 99% of normally experienced ambient temps. The 5w20s provide good protection at those normal operating temperatures. They provide performance that is superior to 5w30 and 10w30 during cold starts and warm up. There is also a slight fuel economy improvement with 5w20.

Personally I'm undecided. My gut feeling is that any good 5w20, 5w30 or even 10w30 at reasonable drain intervals with a good filter will serve you well.

I'm thinkin whatever the owner's manual says is probably right. Mine also says 5/w20

Cheers Everyone for GREAT help :thumbsup:
I finally bought Mopar 5W 20 from the Chrysler Dealer for peace of mind. Now I will go ahead and install Oil Temp/ Oil Pressure / and Volt Meter ;)

Hey Zak,
Trev tracked down an Aussie Amsoil distributor; he doesn't have 5w-20 listed on his site, but he must be able to import it also.
http://www.alphalube.com.au/motor_oils.htm

Happy wheelin', mate.

Great information in this thread about the breakdown of what 5W-20 actually means. But I have looked up all new cars and they are all running 5W-20, even my wifes Hyundai V6 3.3L Sonata. :what?: There are people running this in Alaska all the way down to Austrailia. I dont think the weight matters as much as everyone is making it to be.

Hotter? Use the hiher number viscosity
Colder? Use the lower.

You can safely go up or down one number. :rollingeyes:

Good luck in the down under! Austrailia is loved here in America!

Hillsong anyone?

I have 40 weight Royal Purple in mine and I have no issues yet!:bleh: