if temparture were the case, a simple oil cooler is all that is needed to reduce temps so the oem could still run a 5w20. ever seen an oil cooler for an engine? its basically a large size transmission cooler. their nearly the same thing so its not like we are talking about adding much cost to a car. a single oil cooler and 2 lines dont represent much additional purchase price or assembly time compared to the rest of the car.
If 5w-20 is so good, why do HP variants use 5w-30?
- Thread starter Auto-Union
- Start date
- Status
That sort of makes my point about a hard-driven 20-spec vs a lightly driven 30-spec, plus factor in ambient temps and 20 weight iffy for some people.
What grabs me about the Hemi, is Iam now hearing the 2007, Hemi's 5.7 are calling for 5w30, if you tow. I have a 2006 Hemi 5.7 non MDS, in a 3/4 ton and I have been reluctant to use the 5w20 oil, only cause I live in Florida and its been so hot here. I really dont see the benefits of such a 5w20 in such a warm climate. I think the only fuel savings you obtain are when the engine is driven cold and the 5w20 flows better, when both oils are hot and at operating temps, I will bet that 10w30 and 5w20 are very similar, therefore the warmer theclimate you live in the less benefits you wil actual see. Ive talked to Dodge about this and the dealer claims the 5w20 is only needed to activate the mds because it is a hydraulic setup, and if you have a non MDS, 10w30 or 5w30 will not cause Damage, no other changes were made other than the MDS in the Hemi engines. I was told this by three dealerships and one dealership told me I had to use special Hemi oil, that only Dodge dealers carry or my truck would shut off, I write this dealer off as have hiring his brotherinlaw to run the service department.
And a change in viscosity adds ZERO to the price of the car....
on the surface if you look at it with a simple mind then no it doesnt. but having to carry more than 1 oil is a big issue with oem's and dealers. they ware awalys looking to consolidate oils and fluids in general. it would be very advantageous to an oem to run ALL its cars on 5w20, or ALL of them on 5w30. theres plenty of other reason too but i picked the one i felt was most supportive to reply with.
Simplest solutions are often the best. Ask AE Haas why he would choose a particular viscosity for his Ferrari for a given use. It is, simply, choosing the correct "weight" that matches the operating temperature, in order to obtain the correct viscosity. I consider my answer to be supportive, too.
I agree, i wouldn,t have 5w20 in my truck if i was constantly towing at it's max capacity, but just tooling around w/ 750 Lbs in the bed all the time doesn't really put much of a load on the engine so there is no need to run a thicker oil!
joe
Iam beginning to think they spec the oil more on v8s , because they have the better durability and need the gas milelage push more.
Quote:
Buster,
I have the Hemi in question...the 5.7. the 6.1 Hemi doesn't use 5-20. I think it uses 5-40...I may be mistaken....but I know it doesn't use 5-20. As it's been explained to me, 5-20 is required so the MDS works correctly in the 5.7's. The 6.1's are not equiped with MDS. I've not heard definitive answers as to why the MDS requires it...not that I doubt it, I just haven't heard a solid answer.
Anyone have any insight?
p.s. Yep...over 300HP...I dynoed 320 RWHP a few months back...I've done a couple modifications...but nothing drastic.
FWIW, My neighbor has a Jeep Grand Cherokee SRT8 with the 6.1? L hemi. It is spec'd for Mobil 1 0w-40.
true, until you really are making some power, 5.4l 4v GT (SC), then 5w50 would be Ford spec. Reference at bottom of chart: http://www.ilma.org/resources/chart_oil_recommendations.pdf
Let's say then that it's the temps generated by a higher state of tune that thins the oil a bit beyond what 20 weight can deal with. I still think that the borderline where 20 weight falls short is closer than we think. I'm not uncomfortable with 20 weight in my app with auto trans, but don't feel bad using 30 weight, which most of my stash consists of.
Sure, even in a car spec'd for a 20 weight, if you have a stash of 30 weight; use it! However, I just bought a highway cruiser, with a 4.6 spec'd for 20 weight. I took a couple of cases of my 5-30 stash (two Subarus under warranty) to the auto parts store and swapped them for 5-20 with no problem. Doesn't matter much when you are talking about one weight grade.
From the many views expressed, it just goes to show the number of potential variables involved, beyond the running equipment itself even - operating goals and support infrastructure.
Good discussion everyone.
Take care.
Good discussion everyone.
Take care.
Especially when most the 20's are on the high end, and the 30's on the low side of the scale.
Interesting.
However, when it comes to heavy work it's back to 5W-20. Look up the chart and find the RV chassis with a V-10- it's spec'd for 5W-20. 362hp/457 lb-ft torque, 26,000 lbs. GCWR, and it lives a considerable portion of its life at WOT.
There are tens of thousands of these vehicles on the road with high mileage that are still going strong, so obviously 5W-20 can handle it. There are also a lot of full-size trucks with the same V-10 engine pulling 10k-15k lb. trailers running 5W-20, and as with the RV chassis there have been no oil-related failure trends...
There are plenty of hi-po cars spec'd for oils other than 5W-20- that much is a given. My point was to answer the original question that there are hi-performance variants within a vehicle class that will be spec'd for 5W-20 while the lower-powered versions get 5W-30.
bump
I bet it is a combination of several of the factors mentioned. Seeing as it is Honda/Acura's interest to unify fluids where possible I believe that they have good reasons for calling out 5W-30 in the higher compression, higher output Acura versions.
The new Acura RDX specifies Synthetic 5W-30 which has passed their proprietary HT-O6 test, so I don't think Honda is very worried about motor oil standardization. Note that the RDX is a mainstream smaller SUV and not a specialty car like a Corvette.
The new Acura RDX specifies Synthetic 5W-30 which has passed their proprietary HT-O6 test, so I don't think Honda is very worried about motor oil standardization. Note that the RDX is a mainstream smaller SUV and not a specialty car like a Corvette.
For the record, I'm not sure the TSX 2.4 has higher compression. It might just have higher lift cams or something....plus fueling. fwiw, when I was at Speed World Challenge with RealTime Racing, they used Redline SAE 40 in their TSX....obviously, full race prep and 112 RON.
That's supportive of what I think...that it's temperature that drives the appropriate choice...just like AEHass and his Ferrari.
- Status
