Hemi info galore here, but of particular interest to this audience is the following: Oil Grades and Use. If you have the MDS system, be sure to use 5W20 oil - note that many dealers will use bulk 10W30 or even 10W40, partly out of ignorance (“they really mean 10W40, 10W30 is too light!”) and partly because it’s cheaper - and some dealers know few limits in cheating a few more pennies from a customer. In order for the MDS system to work properly, which is to say to switch from four-cylinder to V8 mode instantly, you need to use 5W20 oil. Of course if the owner’s manual says something else, follow its advice - but don’t be convinced by a mechanic or oil-change place. Insist on the right grade and if they don’t use it...get a refund and go somewhere else. A technical service bulletin (TSB) - 09-015-04 and 09-013-04 - says: “Vehicles with the Multiple Displacement System must use SAE 5W-20 oil. Failure to do so may result in improper operation of the MDS.”
Multiple Displacement System Hemi Must Use 5W-20 Oil
- Thread starter XB70
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if i had a hemi with the mds and got the oil changed at the dealer and then the mds didnt work right. and then i found out it was because they used 10w30 to save a few cents that dealer would have a seriously po'ed person on their hands. another good reason to do it your self.
I would use 15w40. It's a Dodge no matter what you call the engine.
Question. In hydraulicly actuated sytems what does the actuating?
Pressure or viscosity?
Could "Improper operation of the MDS" be slightly less fuel economy on short trips?
uh huh..
What's important to DMC?? Let's see..
According to Chrysler, owners can maximize the effectiveness of the MDS (and increase gas mileage) by:
Keeping to 65 mph or less
Using cruise control to maintain a steady speed
Accelerate more gradually
Using a steady foot on the throttle
That's right. Fuel economy.
Question. In hydraulicly actuated sytems what does the actuating?
Pressure or viscosity?
Could "Improper operation of the MDS" be slightly less fuel economy on short trips?
uh huh..
What's important to DMC?? Let's see..
According to Chrysler, owners can maximize the effectiveness of the MDS (and increase gas mileage) by:
Keeping to 65 mph or less
Using cruise control to maintain a steady speed
Accelerate more gradually
Using a steady foot on the throttle
That's right. Fuel economy.
What about the Mustang GT with the 4.6 3v alum heads and block. Ford says to use 5w-20 like the other 4.6s, but if I take the car out and beat it, and I will, would a thicker oil be better. I am using M1 5w-20 since 1000 miles on the car and I have 5500 miles on the car now. My wife drives it to work during the week and I get it on the weekends.
I saw this today in Motor magazine we get at the shop.
There has to be some leeway I would think. I doubt if a 5w-20 or 10w-30 would set a code.
SAE-40 or 20w-50 might.
I might be wrong though (again).
There has to be some leeway I would think. I doubt if a 5w-20 or 10w-30 would set a code.
SAE-40 or 20w-50 might.
I might be wrong though (again).
Why listen to Chrysler? What do the designers know about engine oil? I'd recommend that you check with an AutoZone or Pep Boys salesperson. You might as well go straight to the source for the real answer on engine oil, viscosity and the right choice for your situation. The truth is that if you don't want to run what the factory recommends, you might want to consider buying a different car.
i don't understand the point of a V8 running on 4-cylinders.
If you want extremely good mileage don't get a V8.
if you want nice power don't buy a 4 cylinder.
Its that simple.
If you want extremely good mileage don't get a V8.
if you want nice power don't buy a 4 cylinder.
Its that simple.
certainly sets you to empty the wallet more and more.
I have a car that has one of these engines, and yes, 5w-20 is important. I cannot recall why, but the link provided by the initial thread explains it in detail. The MDS works really well, I do get 26 MPG just like the sticker said I would (that is of course, at highway crusing speeds, no load on the engine, car not packed full, etc).
As far as technology and gadgets, hey, cars are just getting more complicated, for better or worse. I love all of the technology in my LX platform car, but I do miss being able to actually work on a car. That's just the way it goes.
As far as technology and gadgets, hey, cars are just getting more complicated, for better or worse. I love all of the technology in my LX platform car, but I do miss being able to actually work on a car. That's just the way it goes.
Look at my signature for what weight I use. MDS works just fine and just got back from Houston averaging 20.5 mpg round trip. I doubt the MDS is really not working since I'm not using 5w20. My truck has only seen 5w20 from the factory. 56k and runs like the day I bought it with 123 miles.
Originally Posted By: XB70
Hemi info galore here, but of particular interest to this audience is the following: Oil Grades and Use. If you have the MDS system, be sure to use 5W20 oil - note that many dealers will use bulk 10W30 or even 10W40, partly out of ignorance (“they really mean 10W40, 10W30 is too light!”) and partly because it’s cheaper - and some dealers know few limits in cheating a few more pennies from a customer. In order for the MDS system to work properly, which is to say to switch from four-cylinder to V8 mode instantly, you need to use 5W20 oil. Of course if the owner’s manual says something else, follow its advice - but don’t be convinced by a mechanic or oil-change place. Insist on the right grade and if they don’t use it...get a refund and go somewhere else. A technical service bulletin (TSB) - 09-015-04 and 09-013-04 - says: “Vehicles with the Multiple Displacement System must use SAE 5W-20 oil. Failure to do so may result in improper operation of the MDS.”
I personally mod at a forum with a lot of Hemis. Since 2004 we have been arguing this one out. Here's the real deal:
New gen Hemis run great on almost any oil. If you're under warranty sure you should use the recommended oil. People run these to ridiculous mileages with 20w. So nothing wrong there.
But it will also run just fine on 30w or even 40w/50w. MDS functions are simply ALTERED, not damaged. No harm to anything but your mileage.
So run whatever you want and that Hemi will still be just fine...
Hemi info galore here, but of particular interest to this audience is the following: Oil Grades and Use. If you have the MDS system, be sure to use 5W20 oil - note that many dealers will use bulk 10W30 or even 10W40, partly out of ignorance (“they really mean 10W40, 10W30 is too light!”) and partly because it’s cheaper - and some dealers know few limits in cheating a few more pennies from a customer. In order for the MDS system to work properly, which is to say to switch from four-cylinder to V8 mode instantly, you need to use 5W20 oil. Of course if the owner’s manual says something else, follow its advice - but don’t be convinced by a mechanic or oil-change place. Insist on the right grade and if they don’t use it...get a refund and go somewhere else. A technical service bulletin (TSB) - 09-015-04 and 09-013-04 - says: “Vehicles with the Multiple Displacement System must use SAE 5W-20 oil. Failure to do so may result in improper operation of the MDS.”
I personally mod at a forum with a lot of Hemis. Since 2004 we have been arguing this one out. Here's the real deal:
New gen Hemis run great on almost any oil. If you're under warranty sure you should use the recommended oil. People run these to ridiculous mileages with 20w. So nothing wrong there.
But it will also run just fine on 30w or even 40w/50w. MDS functions are simply ALTERED, not damaged. No harm to anything but your mileage.
So run whatever you want and that Hemi will still be just fine...
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I think MDS is a great technology. you can have your power and get a little help with your mileage. it's no more complicated than the myriads of V-TECH and VVT and VVT-i and whatever.
Nothing wrong with X-20 weight oils. If the engine is designed to use it, then use it. I've had 2 vehicles that called for it, and neither gave me any oil-related problems. One also saw both towing and off-road play.
Nothing wrong with X-20 weight oils. If the engine is designed to use it, then use it. I've had 2 vehicles that called for it, and neither gave me any oil-related problems. One also saw both towing and off-road play.
Originally Posted By: JK
i don't understand the point of a V8 running on 4-cylinders.
If you want extremely good mileage don't get a V8.
if you want nice power don't buy a 4 cylinder.
Its that simple.
No it's not "that simple". Because people who need a truck don't always need the power of a V8. This is especially true for a lot of truck owners who buy simply because without actually having a use for one. Why should people who drive trucks HAVE to suffer from horrific fuel economy? Because you say so?
i don't understand the point of a V8 running on 4-cylinders.
If you want extremely good mileage don't get a V8.
if you want nice power don't buy a 4 cylinder.
Its that simple.
No it's not "that simple". Because people who need a truck don't always need the power of a V8. This is especially true for a lot of truck owners who buy simply because without actually having a use for one. Why should people who drive trucks HAVE to suffer from horrific fuel economy? Because you say so?
A buddy just purchased a RAM Quad Cab 4WD Midbed with the Hemi...
And no receiver hitch.
Why? He didn't notice it when he 1st saw the truck.
Cheers!
p.s. It is a beautiful RED truck, but what's the point of having a pickup without a hitch?
And no receiver hitch.
Why? He didn't notice it when he 1st saw the truck.
Cheers!
p.s. It is a beautiful RED truck, but what's the point of having a pickup without a hitch?
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