Hemi with MDS oil weight

[Dually]

Chrysler states that with the 5.7 liter Hemi with MDS you must use 5W-20 weight oil.Mobil states that any car that specs 5W-20 can use 0W-20The oil has Chryslers MS-6395 number of approval.Joe

 

[Curious Kid]

Why not?

 

[Reg# 43897]

Uh huh. And your point is? Not being snarky at all, just wondering where you are going with this. I have one, too.

John.

 

[Ken2]

The latest copy of "Lubes & Greases," a trade publication, tells of a 100,000 mile test with Las Vegas taxis. They used 5W-20 in half the Ford Windstar taxis and mixed up a conventional, non synthetic, 0W-20 for the other Windstar taxis. Changed the oil every 10,000 miles. Both oils performed excellently.

Use the 0W-20 with no concerns. You will get slightly easier starts when very cold, and slightly better gas mileage before the engine is up to temperature.


Ken


Ken

 

[Dually]

My point was that Daimler/Chrysler may not honor a oil related warrenty concern when using 0W-20.Also I think many people in Europe are using the 5w30 weight of oil.If you use the 0W-20 oil your covered(warrenty)by Mobil but Daimler/Chrysler may not even thoughtthe oil spec has a Daimler/Chrysler approval.Joe

 

[Lonnie]

Can you tell me, in a failed engine, how one would tell the difference between a 0w-20 and a 5w-20 oil? Could the exact viscosity of a contaminated oil be a bit difficult to pin down? Might there be a range within the accepted definition of viscosities that would cloud the issue? And would it take some real doing to prove that the 0w-20 was the cause of the failure and did something that a 5w-20 would not do. If they wanted to put it on you they'd just claim you didn't change the oil often enough, ignore your receipts and stick you with the bill.

 

[Rand]

Technically speaking.. since a 0w20 exceeds a 5w20 it could
also be considered a 5w20...
And I dont know how they would prove otherwise..

"oh it flows better than spec at -42 degrees..
we gotta deny the claim here joe!."

 

[2006_Charger_R/T]

I purchased a Charger R/T earlier this year and muttled the same question about the HEMI's MDS feature regarding oil weight. My car's owners manual states that 5w-20 is required for the HEMI's MDS feature to operate properly.

From all the reading I have done, I have came a few conclusions but I can't back them up with proof.

1. The 5.7L HEMI w/ MDS runs fine on 5w30 or 10w30 oil. People have claimed that the HEMI's gas saving MDS feature still works fine, but I have yet to see the proof.
2. Using 5w-20 is the recommended weight according to DC, but people speculate that reasons for using 5w-20 seems to point more to EPA ratings and not the MDS system.

I use 5w-20 and I have been doing used oil analysis at every OC. The used oil analysis have came back good. 5w-20 works fine. I'm sure using 5w30 will work fine too.

 

[Lonnie]

Do you think that DC knows something about oil viscosity? If so you might want to consider following their requirements. Or you could ask the lot boy that became a mechanic.

 

[Ramjet Roger]

My understanding of the MDS implementation relies upon turning on/off oil to the lifters on 4 cylinders. The key to the smoothness of this toggling--supposedly 40 msec or less--is precise hydraulic pressure. Changing the viscosity of the oil would impact the pressure at operating temperature. I suspect that, depending on the specific oils in question--there may be some overlap between the 5W20 and 5W30 viscosities. Some of the used oil analysis on this forum indicate that many 5W30 shear down to 5W20 range pretty quickly. All things considered, I see no reason to vary from DC recommendation. I've seen no difference in used oil analysis on my Hemi with 5W20 and 5W30.

Roger...