5w50 in 5w30 car?

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I have a high mileage Mazda 2.2. I've been using synthetic 10w30 and 5w30 in it for a while. My last oil analysis showed higher than normal lead and copper - probably normal for such high mileage and on that OCI many very short trips in very cold weather (-15C or colder, 3 km trip)

Anyway, I was thinking of using 5w40 Rotella on my next change to give the engine a little thicker oil - given than it has very high mileage and the tollerances inside are probably quite larger than when new. This would help cusion the main bearings etc. and hopefully help her out a little as those bearings start to show wear in the UOA.

However, this got me thinking, maybe 5w50 would be better for the same reasons. I do live in a cold climate, winter can reach -25C or colder regularly, so the 5w is important at startup. But the 50w could be even better for the worn out engine when at temperature. Both 5w40 and 5w50 Castrol are on sale at a local store. I've looked around and it's hard to find 0w here.

Any possible risks or downsides to using 5w50? Maybe I should look harder for a 0w40 - maybe that would overall be better given the climate conditions?
 
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rotella has a 0w40 avalible at canadian tire and partsource. it seems to be a "Canada" only available oil....it would probably be your best bet.
 
Rotella T 5w-40 seems to have a pretty large following.
I am running it my Expedition over the winter,from what others have reported there should be no problem.
 
Originally Posted By: Trav
Rotella T 5w-40 seems to have a pretty large following.
I am running it my Expedition over the winter,from what others have reported there should be no problem.


Agreed. Or Redline 0w-40 should work well as well and give the hot protection of a 50wt.
 
I wonder how many miles and does the engine make noise, burn oil, or have low oil pressure? Just because an engine has some miles on it doesn't mean it necessarily would be beter off with a heavier oil especially in a cold climate.
 
A five fifty should cause no problems.
Be aware, though, that this will be a thicker oil than a 5W-XX or 0W-XX at low temps.
5W is a range, not an exact value. A 5W-50 will be thicker when cold than a 5W-30.
 
I would say to go with a 0W-40 engine oil!

Mobil 1
Red Line
Shell Rotella T

There are other brands too...but I think you will find these ones much easily...for the sake of convenience go with Mobil 1

but I have never seen an oil who has lower pour point than Red Line in this grade (oh yes I have, but that's a diesel oil)
 
Originally Posted By: sprintman
There is no such thing as a '5W30 car'


He means a car spec'd to run 5W-30. But you knew that.

OP, you should be able to find M1 0W-40, that's a very good oil and lots of places carry Mobil products.
 
Originally Posted By: hate2work
Originally Posted By: sprintman
There is no such thing as a '5W30 car'


He means a car spec'd to run 5W-30. But you knew that.

OP, you should be able to find M1 0W-40, that's a very good oil and lots of places carry Mobil products.


He knows that, but for some reason he had to write a post saying that.
 
I call it a 5w-30 engine because that's what the owner's manual calls for in virtually all temperature ranges (including mine).

If it were a massive diesel engine that needed 20w-80 or something, we would be talking a different scenario. But since the manufacturer called for 5w-30 back in 1991 when API-SE (or whatever) was the standard, I call it a 5w-30 engine so we can compare what the manufacturer called for when new (and back when oil was not what it is now) to what I may put in it now.

High mileage is 305,000 km on the clock. That's about 190k miles. Not all of them have been kind either. It makes very little noise, runs well and still gets excellent mileage. It runs very much like it did when I bought it 200k km's ago. The UOA said Lead 63, Copper 105. The rest of the values were more or less inline. If I can find it I'll post it.

That UOA was over an 8k interval, almost all city driving, much of it a 2.5 km trip to work and back where the engine never got up to temp. Much of those trips were at -15C or -20C, so the temp needle didn't even move by the time I turned the engine off. It was a mix of Valvoline Synthetic, 10w30 and 5w30 and an AC Delco filter. Probably the worst thing you could do to an engine other than run it dry of oil.
 
The massive diesel engines use 30 wt. crankcase oil. Mid size engines, like locomotive engines, use 40 wt.

I'd stick with 5W-30 in your winter because that oil may never get warm and thin. Don't confuse the coolant temperature in the head with the oil temperature. In the summer a 5W-40, 10W-40, or 15W-40 might work out well in that worn engine with larger clearances than they were when new. (Clearances are the gaps for oil flow. Tolerances are the allowable error in the clearances.)
 
Originally Posted By: sprintman
I'll try a didfferent tack. There are no engines built for particular viscosities. Clearances havn't changed for decades (tolerances have). Make sense now?


I agree with what you have said on part of your post, and glad you noted the difference between clearance, and tolerance. What has changed other than the above is features using oil pressure to accurate accessories, as well as many other things such as sump size, oil galleries, size of passages, not to mention going from cast iron everything to many aluminum parts including heads in the engine. The OP should have no problem with just about any oil he chooses, however I'm not sure a heavier weight oil will cushion anything better than OEM spec oil, also I'm not sure load bearing is the major failure of 98% of engines, I would guess it's oil starvation, or heat (heat could also be due to oil starvation) so in theory a lighter weight oil would give overall better lube properties except in the ring/piston to bore seal.... in the case a heavier weight oil may in theory give better results, then again a nice high mileage oil like Maxlife would give many of the properties the OP is searching for. The Shell Rotella T 5w-40 is one of the best all around oils I have ever used, from gassers to diesels it's an outstanding oil, and also works great in the high mileage category.
 
A chemical engineer friend of mine told me the "high mileage" oils are often a blend of a variety of different grades that average out to whatever is printed on the bottle. The theory (as he explianed it) was the thicker oil will get stuck in the larger gaps and worn seals while the thinner stuff will find it's way into the smaller clearances (thanks for clarifying the nomenclature, I knew that but forgot to use the right verbage).

Anyway, I'm not sure of how good it is, but I used some conventional "high mileage" stuff a while back and I think I burned a little more than usual, it didn't seem to help or do anything substantial.

I think I will look for the Rotella 0w40. Thanks for the good input.
 
Originally Posted By: rclint
Originally Posted By: sprintman
I'll try a didfferent tack. There are no engines built for particular viscosities. Clearances havn't changed for decades (tolerances have). Make sense now?


I agree with what you have said on part of your post, and glad you noted the difference between clearance, and tolerance. What has changed other than the above is features using oil pressure to accurate accessories, as well as many other things such as sump size, oil galleries, size of passages, not to mention going from cast iron everything to many aluminum parts including heads in the engine. The OP should have no problem with just about any oil he chooses, however I'm not sure a heavier weight oil will cushion anything better than OEM spec oil, also I'm not sure load bearing is the major failure of 98% of engines, I would guess it's oil starvation, or heat (heat could also be due to oil starvation) so in theory a lighter weight oil would give overall better lube properties except in the ring/piston to bore seal.... in the case a heavier weight oil may in theory give better results, then again a nice high mileage oil like Maxlife would give many of the properties the OP is searching for. The Shell Rotella T 5w-40 is one of the best all around oils I have ever used, from gassers to diesels it's an outstanding oil, and also works great in the high mileage category.


My experience with a worn engine and I have lots of it is a thicker oil does help cushion things. Very noticable in the amount of noise it makes. On the extreme end of things was a rod knock that I nursed for a year on Valvoline 60wt until I had the funds to rebuild. On a 40wt I was afraid to stand next to the car with it running.
 
Originally Posted By: Gannet167
I call it a 5w-30 engine because that's what the owner's manual calls for in virtually all temperature ranges (including mine).

If it were a massive diesel engine that needed 20w-80 or something, we would be talking a different scenario. But since the manufacturer called for 5w-30 back in 1991 when API-SE (or whatever) was the standard, I call it a 5w-30 engine so we can compare what the manufacturer called for when new (and back when oil was not what it is now) to what I may put in it now.

High mileage is 305,000 km on the clock. That's about 190k miles. Not all of them have been kind either. It makes very little noise, runs well and still gets excellent mileage. It runs very much like it did when I bought it 200k km's ago. The UOA said Lead 63, Copper 105. The rest of the values were more or less inline. If I can find it I'll post it.

That UOA was over an 8k interval, almost all city driving, much of it a 2.5 km trip to work and back where the engine never got up to temp. Much of those trips were at -15C or -20C, so the temp needle didn't even move by the time I turned the engine off. It was a mix of Valvoline Synthetic, 10w30 and 5w30 and an AC Delco filter. Probably the worst thing you could do to an engine other than run it dry of oil.


'Lead of 63' and 'copper of 105' on a broken-in, high-miles engine is NOT good.

Some serious problems going on with that engine that oil will not fix......
 
Originally Posted By: BuickGN

My experience with a worn engine and I have lots of it is a thicker oil does help cushion things. Very noticable in the amount of noise it makes. On the extreme end of things was a rod knock that I nursed for a year on Valvoline 60wt until I had the funds to rebuild. On a 40wt I was afraid to stand next to the car with it running.


However the OP is talking about a good running engine, with no loud noises, nor any abnormal wear that he can tell. In your case I agree a thicker oil may work, however in the OP case, and from the information he gave I think sticking to OEM spec or close (he is already using an outstanding HDEO 5w-40) would be a good choice, however changing oil, different brands, weights, synthetic, dino, even mixing your own is a freedom we all have, tis what makes it all worth while.... Would you have gone that thick in your engine if it was in normal good operating condition, just high miles ?
 
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