The Test Has Begun... 5w20 vs. 5w30.....

[HerrStig]

Weather changes DO make a difference in how an engine runs, especially with all the feedback built into modern EFI systems.
High humidity reduces the amount of O2 available, but also lowers octane requirements. Enough to notice...maybe... if the exhaust sensors notice a difference in O2 content in the exhaust the feedback to the ECU wil change.

 

[WMSmotorhead]

Originally Posted By: mechtech2
WMS Motorhead is simply making a few provocative posts here and there in BITOG.
It's the best he can do.


Sort of, and sort of not. The objective was to find out if there was a difference in the way a vehicle runs on 5w30 vs. 5w20, so when I make the switch, not telling anything except, "Oil Change Done"... I wanted to know if there was any difference in the way the truck ran.... or if it was all a mental thing.

Seems plausible that you can "feel" the difference between the two, but I don't think that the vehicle is at any risk by this experiment. It was fun.

I don't plan to put the funding in to make this "scientific"... but for fun, I'll see again in a few months what happens going back to a 5w-20..... again, not saying anything, we'll see if she finds a new change in the way it runs.

 

[weebl]

I don't think anything will be noticed. I've switched brands on my vehicle and my wife doesn't notice anything, and neither do I. I used 5W-20 for once OCI when I normally use 5W-30 and again nothing. Same goes for prior vehicles owned - brand changes = nothing. Using 5W-30 and 10W-30 alternately and nothing.

Even with my brother's old car prior to him getting rid of it, it was factory spec'd for 10W-30, but was consuming oil. He used 20W-50 at the end. Only thing either of us noticed is oil consumption went down.

The reality I think is that you will not have any significant differences in wear over a very broad range of viscosities for the majority of engines. Fuel economy may change very incrementally, and not really noticeable unless carefully measured.

 

[Jaymus]

Sounds fun, WMSmotorhead. It appears that she may already notice a little something? I once switched to Rotella 5W-40 in my grandmother's 2000 Buick Park Avenue without telling her (Calls for 10W-30 on the oil lid/had been using GTX 10W-30), and within a couple of days, I was hearing about how much noisier her engine was. (BTW, it actually was making a couple of ticks now and then from the top of the engine, so it really didn't like that oil).

I'm a fan of RTS 5W-40, but the GM 3800II does not like it.

 

[TFB1]

Originally Posted By: WMSmotorhead
I think most of these "Miracle Cures" are placebo. I.E. My car runs sooo much better with MoS2 but only the German kind.... Umm.. Ok... whatever.

Agreed, in over 45 years of vehicle ownership I've observed a noticeable change in operation twice...

First was MMO in a 390 Ford, made it sound like the proverbial sewing machine, everything in it clattered... Drained it out and have never used the stuff again...

Second was more recently when my neighbor gave me some 20W-50 Amsoil racing oil I put in my street/strip T-Bird... It was a bit more sluggish and lost approx .15 sec at the drag strip... Switched it back to 5W-30 and it "freed up" again... As far as sound, wasn't any noticeable difference...

 

[SwampSurvivor]

My Jeep seems to run smoother for a week or so after an oil change.

 

[chiks]

Originally Posted By: weebl
I don't think anything will be noticed. I've switched brands on my vehicle and my wife doesn't notice anything, and neither do I. I used 5W-20 for once OCI when I normally use 5W-30 and again nothing. Same goes for prior vehicles owned - brand changes = nothing. Using 5W-30 and 10W-30 alternately and nothing.

Even with my brother's old car prior to him getting rid of it, it was factory spec'd for 10W-30, but was consuming oil. He used 20W-50 at the end. Only thing either of us noticed is oil consumption went down.

The reality I think is that you will not have any significant differences in wear over a very broad range of viscosities for the majority of engines. Fuel economy may change very incrementally, and not really noticeable unless carefully measured.


That is bound to happen when you drive vehicles whose engines are totally disconnected from the driver's zone of feel.

 

[chiks]

Originally Posted By: MrOctober44

I had a Mazda6 which required 5w-20.
Once after a Mobil1 full synthetic oil change at the Mobil1 station, the car did not quite have that "pep" as I drove out. So I turned around and asked the Mobil1 guy what oil he put in. He replied "Mobil1 5w-30".

nuf said about the difference about 5w-20 and 5w-30.

That a bunch of Bull!!!!!!!!!!! maybe 40 or 50 weight oil, My wife say the car seen to be faster after i wash it

Bull to you. Not to me. I just told you what I experienced. If you see God, do I call bull?

 

[MrOctober44]

Chilk, did`nt to hurt your feeling,You have your opinion and i have mind!!

I thought was talking about OIL, 5w20 and 5w30

 

[HWEaton]

I have about 4 ranchers with Ford F-150s, a 2000, a 2002, and two 2003's. All different owners and they all insist I put Mobil Super 5000 10W/30 in them. Each pickup has over 150,000 miles and none of them have any engine problems whatsoever. They may be missing some MPG, but they probably don't know or care. The only time the pickups hit asphalt is to come to my shop & the feed store.

 

[donnyj08]

im betting the 5w20 protects better, runs smoother (not that the human body will tell) and provides the best fuel economy all at the same time. and im betting the engine will consume more oil on the 5w30. some of the modular ford trucks from 97-01 that were spec'd 5w30 were consuming quite a bit of oil, but when switched to 5w20 per ford service bulletin used less oil. thinner yet providing less consumption.i know first hand owning a 97 4.6 f150 and a 99 v10 350. both consume considerably less on 5w20. and both have high mileage. 269k and 211k respectively. 5w20s are great, dont doubt the thin stuff!