So what happens to a car when.... any help? haha

[Dooms_Bane]

YA OK... so my car takes 5W-30...
and since i was in a MAD rush i bought some 10W-30 without looking.. thinking it was 5W-30......
then i poured it into the engine...
after i started driving around.. for say? 2 minutes? the "check engine" light turns on so i'm like WTF?!?! so i take a look at the oil i'm like
oh ShAt.....
so i drive to part source.. grab me some 5W-30
run to my house change the oil.. then start driving again.. i notice when i start the car... it makes a weird noise.. might be paranoid but i'm sure my car is slower now...
BUT.. if i rev my engine really hard... then i drive around for a bit... turn off my engine.. start it again.. starts fine..
but if i leave it off for abiout? 2 minutes... then start it, it makes weird noises.... but other than that it drives fine... just wondering if their are ANY odd crap i should be looking for.. and if theirs anyway i can turn this stupid check engine light off without going to a mechanic.

[AllGoNoShow]

Changing from 10w-30 to 5w-30 will not make your engine make wierd noises and throw CEL's all the time unless its a pos and you need a new car anyways...

With that said, the difference is the viscosity of the oil, how it flows/lubricates.

Your approching this wrong, you hear the noise, the car is throwing a CEL, which means YOU TAKE IT TO A MECHANIC, you get it looked at. They don't f***in put CEL's on so people can learn to turn them off, they put them on to tell you there is a problem and you need to get to scanned and checked out, its there to help you prevent/fix problems like little noises, not erase the light and have bigger noises later.

[Dooms_Bane]

haha aight.. just checking didn't wanna end up spending a few hundred to bring it to a mechanic when later on i find out it would have only take me half the price to fix it myself...
but it just started happening after i stuck the oil in...
it's a 2001 car anyhow... so can't be to old
but thanks

[BlackArcher101]

Here in Canada, you should almost be using 2 types of oil anyway. Mine uses 5W30 in the winter time (less viscous cause anything more and it just won't start or lubricate)... and now in the summer I run 10W30, cause I need the extra protection.

[Dooms_Bane]

maybe i am just going paranoid... cuz i thought oil shouldn't do that to.. maybe it's my cat converter or some shiit? i'll check the filters and crap...
thanks tho hey....
feel stupid now haha.. real stupid LOL

[Zero102]

Running 10W30 in an engine designed for 5W30 wouldn't cause any damage in that short of a time. It would be just like starting your car in slightly cooler weather, since the cold viscosity of the 5W30 would be similar to a warmer viscosity of the 10W30 oil. It would be pretty harmless.

That said, bring your car by Auto Value to have the CEL checked out, seems to me they read codes for free.

[schmooot]

your oil has nothing to do with it, just bad timing thats all, maybe you knocked some sensor during your oil change or something

[Zero102]

^^^ Most likely cause.

[ken-gsr]

yup sounds to me like shity timing

[Darkane]

This is a super long shot but if it is an older motor maybe the 10W30 just that once couldn't make it to the rod bearing in time and it developed a small knock? Of course this is worst case senerio(sp) so dont sweat it. Actually happened to my dad but on a 275km ford 3.0L. :thumbsup:

[Foz]

I change from 10W30 to 5W30 seasonally. No problems at all. Shouldn't throw a CEL.
It's something else other than the oil.

[Dooms_Bane]

HAHAHA i got it checked... it's some stupid lean gas thing?
something abou tmy engine not getting enough gas? he just reset the thing and put soemthing in my gas tank..
car starts fine now...
got my speed back HAHAHA.... it was slow..
he said engine was doing something... something with the gas...
said if CEL comes back on.. just bring it back he'll see whats wrong other than that it should be fine.
i guess i just have shitty timing..
curse me and my lack of knownledge

[arian_ma]

Old bump, didn't want to start a new thread.

I did something similar to this yesterday, my previous car took 5W30 and my new car takes 10W, but it's my first oil change with the new car and I am so used to buying 5W I bought some synthetic Castrol Syntec 5W30 and did the oil change. My car runs quite a bit smoother now, but that's probably because I waited almost 5K before changing the oil.

Anyways, I was just wondering about the potential hazards to running 5W30 in a car that asks for 10W30, specially in the heat of the summer. Should I change my oil again? Or is it alright till the next oil change?

Thanks!

[Black Gts]

The only difference should really be in start up temp. In the summer it shouldnt hurt as much, but in winter a car with 10w30 may have a bit more trouble starting.
Correct me if Im wrong but 5w is 5x thicker than water at zero degrees, and 10w is 10x thicker than water at zero degrees.

[Mangina]

Originally posted by Black Gts

Correct me if Im wrong but 5w is 5x thicker than water at zero degrees, and 10w is 10x thicker than water at zero degrees.

That's very wrong. But you can interchange 0W30, 5W30, and 10W30 during the summer. They all act the same once your oil has warmed up.

[PINOY-X]

u can mix 5w30 to 10w30 or 20w50 if u wanted as long as they are they same brand .. and no different additives is mixing together ..

[Black Gts]

Originally posted by Mangina


That's very wrong. But you can interchange 0W30, 5W30, and 10W30 during the summer. They all act the same once your oil has warmed up.


I meant at start up temp... so what your saying is kinda the same thing..

[Zero102]

No they don't.
The W30 puts it within a viscosity RANGE, it does not mean an exact viscosity.
A 5W30 will always be thinner than a 10W30 of the same composition. Running a 5W30 oil in an engine designed for 10W30 isn't the end of the world, but don't make a habit of it. 100,000km of that could be bad for it ;)

Seriously though, it is a measurable difference when doing oil analysis, and it is noticeable to the engine. The thinner oil will provide a lower film strength than the thicker oil, although it will circulate better at startup.

[forced_eg]

it wont cause any problems right away, if you put 10w30 in place of 5w30 then you may starve your cylender walls of oil, and if you have 530 in place of 1030 you may burn a cunthair or two

[Annoyingrob]

Originally posted by Zero102
A 5W30 will always be thinner than a 10W30 of the same composition.
Are you sure? It will be thinner when cold, yes, but once they both get hot, they should both approach the same viscosity. That's what the two numbers are for on the oil. Eg: 5w-30 is 5 weight when cold, and 30 weight when warm.

[Mangina]

Originally posted by Annoyingrob

Are you sure? It will be thinner when cold, yes, but once they both get hot, they should both approach the same viscosity. That's what the two numbers are for on the oil. Eg: 5w-30 is 5 weight when cold, and 30 weight when warm.

That right. But the 30 is still a range, so it's possible to have 0W30's or 5W30's that are thicker than 10W30's once they are hot. (Or vice versa) I have a 0W30 in my truck right now that is one of the thickest 30 weight oils on the market. I know Mobil 1's 5W30 was thicker than it's 10W30 for a long time.

[Zero102]

Originally posted by forced_eg
it wont cause any problems right away, if you put 10w30 in place of 5w30 then you may starve your cylender walls of oil, and if you have 530 in place of 1030 you may burn a cunthair or two

Wouldn't be worried about starving the cylinder walls of oil, they are a lot less dependant on the oil's film strength, I would be worried about starving the rod bearings and cam lobes. They care a lot more about how strong the oil itself is.
Typically when you see a 10W30 requirement it means that the manufacturer is worried about one of those 2.

As I mentioned above, the last number is a range, not an exact number. The first number is also a range, but of a completely different measurement.
So, quick summary, you can have a 5W30 that is thicker than a 10W30 but it will have more viscosity modifiers in the oil, which makes it more likely to break down or go out of range viscosity-wise.

Also, 5WXX and 10WXX don't mean that the oil performs like a 5W when cold. It is more complicated than that, because it's on a completely different scale. To be honest, they are arbitrarily assigned numbers based on cranking resistance at a fixed temperature. To qualify as a 5WXX oil you must have Y resistance or lower at a temperature of between A and B degrees. I forget the exact numbers, but the entire scale is arbitrary, that's how it is possible to have 0WXX oils. There is no way in heck that something could perform as well as a 0 viscosity fluid when cold, unless we're talking about some things that should absolutely never exist within a car engine.

Questions like this are best answered over on BITOG.

[Zero102]

Originally posted by forced_eg
you may burn a cunthair or two

Oh, and if you burn a cunthair or two, you're sitting in the wrong seat, or just plain driving the car wrong :angel:

[arian_ma]

Thanks a lot guys, makes me feel a little safer, I'll try not to run 5W for 100k
:D

[forced_eg]

Originally posted by Zero102


Wouldn't be worried about starving the cylinder walls of oil, they are a lot less dependant on the oil's film strength, I would be worried about starving the rod bearings and cam lobes.

???

0.002-0.005" is plenty for main bearings, rod bearings and cam journals (not lobes) 50w or 0w30 its still getting in there,

wouldnt be worried about starving the cylinder walls??? oil retention in cylinder wall crosshatch is critical, dont tell me you thing metal on metal is good for the motor

[redx2nv]

Look up the Esso oil weight comparison(vid).

When its -30, 20w50 will take a minute or so of metal on metal contact, that shits like syrup when its cold.

0w50 flowed to the journals within a few seconds.