oil change completed: but w/5-30 ???

Joined
7 September 2003
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2,992
Location
Newport, CA
i just got my oil changed completed, and its only after it was done, that i realized the tech's used 5-30 mobile 1 synthetic. i know most people on prime have been recommending 10-30, should i be concerned with the 5-30? have them flush and redo? or will it not make much a difference?
 
Dali shows RP 5W30 as the 'best oil' for the nsx, but after coming across a number of posts here on prime I got nervous not only about the weight, but also about the brand Royal Purple. I know several people who use RP in their engines, just as I know 5W30 *should* be fine for us here in SoCal, but the nagging thought that the oil running through my engine might not be the best got me to swap it out for some amsoil 10W30 after only 700 miles. It's better to spend the money getting it changed out, or complain and get the proper recommended weight, than to have the worry in the back of your head everytime you wind up your nsx (imo).
 
5W30 is recommended by the manual for lower temperatures. I don't think SoCal is cold enough for this oil. :)
 
during colder months, my local acura dealership puts 5w-30 in my nsx.
 
5W30 is fine for the NSX. I use Mobile 1 5W30 in my NSX as do others I know. It is a multi-weight oil like the 10W30.

Many cars now specify 5W30 (Toyotoa, Lexus, Acura, Honda, etc, even my 5.4L V8 Ford Expedition) because it is claimed to aid in increased fuel economy when the engine isn't fully warmed up.

It is not much different from 10W30, except that it is designed to be more fluid (less viscous) in colder weather (this aids in cold start up as well). As far as being worried about how it behaves in hotter weather, you are fine there too because it is a 30W oil for hot temps. So, "winding" up the NSX with 5W30 won't "hurt" your car. Remember, it is an NSX - it is built better than most cars out there and a slight difference in multi-weight oil viscosity isn't something to worry about in the back of your head.

There is no need to have it flushed - that's just a waste of time and money. Use it and go back to 10W30 on your next oil change if you want.
 
thanks for all the knowledgable suggestions... appreciate it...
 
ChopsJazz said:
It's not just most people who recommend 10/30, the owner's manual does too.

That's probably because when the car was first introduced in 1990 you couldn't get a quality 5W30 oil. Changing the owner's manual later on would have created a flood of confusion, phone calls, emails, snail mails to American Honda much like what we have ton endure here on Prime so I'm guessing that's the main reason they didn't change it. :)
 
Hugh said:
That's probably because when the car was first introduced in 1990 you couldn't get a quality 5W30 oil. Changing the owner's manual later on would have created a flood of confusion, phone calls, emails, snail mails to American Honda much like what we have ton endure here on Prime so I'm guessing that's the main reason they didn't change it. :)

That's an awful lot of speculation and conjecture.
 
I use 5w30 as well. My local Acura dealer recommanded it. Elf F1 Sythetic
 
mickeylex said:
It is not much different from 10W30, except that it is designed to be more fluid (less viscous) in colder weather (this aids in cold start up as well). As far as being worried about how it behaves in hotter weather, you are fine there too because it is a 30W oil for hot temps. So, "winding" up the NSX with 5W30 won't "hurt" your car. Remember, it is an NSX - it is built better than most cars out there and a slight difference in multi-weight oil viscosity isn't something to worry about in the back of your head.

"more-fluid" when cold translates into increased wear on the engine, this concern aside the differance in weight we are discussing is minimal, but if the thread-starter was concerned enough to come onto prime and create a post asking for advise certainly paying the $50 or so to have the factory recommended weight of oil put in his car is a cheap way to regain that 'warm and fuzzy' feeling when driving his nsx... $0.02, something this easily corrected is too trivial of a concern to have when driving.
 
j14nsx said:
A 5w30 and a 10w30 will have the same viscosity at 100deg as each other.

The 5w will flow round the engine quicker at start up and cold than the 10w.
(Being Engerlisch, j14nsx means Celsius when he is quoting 100 deg) :biggrin:

Exactly though - it might be good for some members to educate themselves on understanding what the numbers in a multi-viscosity oil mean, rather than just quoting what the tried & trusted manual states.

Considering few members here have their cars in the -35 deg environment (Celsius or Fahrenheit - they're close to same!) but for those who do, 5W represents a better option for added 'flowability' at that extreme cold.
All-in-all makes not much difference for most of us, but 5W-30 will accommodate the extreme cold better. In CA climate, there is probably no discernible difference at typical starting temperatures.
The Society of Automotive Engineers (SAE) has established a scale which indicates oil thickness (viscosity). SAE numbers include, for example, 10W-30, 5W-40 and sometimes just a single number such as 5W, 10W, 20, 30, 40 or 50. The "W" next to a number means the oil thickness was measured at a very cold temperature, as low as -35 degrees F, when the oil is thickest. A number without a W suffix indicates the oil thickness was measured when the oil was hot (210 degrees F).
Two numbers separated by a hyphen indicate a multiviscosity oil. Multiviscosity oils are tested at both hot and cold temperatures and are recommended for all-season use. Multiviscosity oils are able to lubricate moving parts over a wide range of temperatures. These oils contain a viscosity index improver or polymers to change the viscosity of the oil as temperature changes. A multiviscosity oil such as a 10W-40 will function like an SAE 10W oil at cold temperatures and like an SAE 40 oil when the temperatures are warm or hot. Note that a multiviscosity oil can not be made by combining individual SAE oil viscosities together. Multiviscosity oils require the addition of polymers in order to gain the ability to function differently at different temperatures. Equipment operator's and service manuals specify which oil viscosity should be used under specific weather conditions.
 
The factory recomended oil for the NSX is 10W-30 and thats what I use. I would expect any place I paid to do an oil change would use 10W-30. I ran into this with the (ex)wifes Honda Del Sol SI back in 97. Most Honda's were using 5W-30 at that time and the Del Sol SI required 10W-30. I called Honda customer service in CA and asked what weight oil I should be using. The guy I talked to first said 5W-30 was fine then he put me on hold and talked to the engineers. He came back on the line and said in so many words he got his ass chewed out. The recomended oil was 10W-30 and that was what I should be using.

As a side note I have seen 10W-30 at -22 degrees F it's as thick as cold honey.
 
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scorp965 said:
have the factory recommended weight of oil put in his car is a cheap way to regain that 'warm and fuzzy' feeling when driving his nsx... $0.02

I agree on that point; I personally wouldn't change it and you would - nothing wrong with that. If he wanted the "warm and fuzzy" then of course he should change it out. No reason to worry about it if it is a concern.

OTOH, it sounded like JDMnsxR asked if there would be a difference with using 5W30 for this particular oil change, and as most others have stated, it won't be a problem for the NSX.
 
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when i switched over from 10w-30 to 5w-30, i noticed a difference in the car's throttle response. alot more smoother, and responsive. did you?
 
my suggestion, don't worry about it. it's a little 'lighter' than 10w-30 (hence the winter usage of 5w-30 b/c lack of extra heat), but not going to be detrimental to your car's internals or performance. mobil 1 5w-30 is definitely a safe substitute for any 10w-30.
 
Does anybody use 0w-40 in their cars? I've used this for my last car, a BMW M Coupe, and it performed wonderfully.

Thoughts?
 
6i9 said:
Does anybody use 0w-40 in their cars? I've used this for my last car, a BMW M Coupe, and it performed wonderfully.

Thoughts?

0W-40 is frequently used to lubricate the pavement in front of the tires of BMWs with seized engines and/or trannys to help get them on the flatbeds more easily. :)
 
6i9 said:
Does anybody use 0w-40 in their cars? I've used this for my last car, a BMW M Coupe, and it performed wonderfully.

Thoughts?
I've been wondering about this too, and oil weights in general. I have a supercharged '91 with low mileage. The previous owner (my father) gave me some jugs of 15w-50 Mobile 1 with the car. I can't tell if this is a really good idea, really bad idea, or something less extreme.

The owners manual recommends 10w-30. The recommendation was crafted with conventional oils in mind in 1990 when motor oils weren't as good. Today conventional oils are better, not to mention synthetics. I'm also confused about the spread...do I read it right that they want an oil that is thick (relative to 5w and 0w) at startup and thin (relative to 40 and 50) at temp?

Reading this article doesn't shed much clarity as the guy seems to be suggesting Mobile 1 in both 0w-40 and 15w-50. I am happy to read that the 15w-50 Mobile 1 "flows far better than conventional 10w oil at startup" but less happy to read "the users of this oil are not concerned with Fuel economy" and a little put off by "So if your cherished car has high oil consumption, smokes on turbo overrun, has hydraulic tappets that clatter or has a flickering oil light on Mobil 1 0W-40 or other lower viscosity oils then this may just be the answer to your problems."

My first impression from the article is that with a low-mileage engine in good condition that 0w-40 would be the recommendation, but at the bottom the guy essentially says high-performance engine should get 10w to 15w on the low end and 50 on the high ("SOUNDS A LOT LIKE MOBIL 1 MOTORSPORT !" is the quote, and Mobile 1 Motorsport = 15w-50) then there is a note (I think not by the guy from Mobil1, but from someone else) that seems to summarize the article as a recommendation for 0w-40 ("So top it all off Harvey I wouls stick some Mobil1 0w/40 in your MR2." is the quote).

Can anyone with real experience/knowledge and lots of it (like Mr. Basch, Larry B, or an engine designer for Honda...i.e. not just some naysayer) shed clarifying light on this?
 
5/30 vs 10/30 not going to make any difference unless you run the car in much colder climates.Now 20/50 is another story.I used this once but as Pa. summers go I had numerous mornings where temps were below 65 deg and guess what,tough to start.Had to crank it a bunch to get going.
 
Logically I don't see how 5W-30 could be detrimental in any way. I want my oil to circulate quickly at starup, reaching the top portion of my engine fast. Since I'm not pushing the engine at that point, I'm not so worried about less viscosity between my pistons and cylinder walls at that time. When the engine warms and I begin to push the motor, the oil has thickened and I have normal piston-cyl. wall lubrication.

I would think that in a cold climate <32*, 5W-30 would indeed be superior to 10W-30. I want the fastest oil flow at startup. If 10W-30 is designed to work at "normal" temps than what if you are far below normal? 5W-30 just seems safer.

I do also believe that the oil technology of 1990 strongly influenced Honda's choice to use that as the recommended type. 10W-30 will suffice in nearly all situations and instead of messing around they simply put that and left it alone.

BTW, the owner's manual also recommends oil changes no more frequent that 7,500 miles. So if everyone is taking owner's manuals as holy gospel consider that. Maybe 3,000 miles is better than 7,500. And maybe, just maybe, 5W-30 might work a tad better than 10W-30.
 
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