going from 5W-30 to 10W-30 for an engine over 100k miles

[ekprimal]

Hey all, was curious on your thoughts about moving from 5W-30 to 10W-30 on a D series engine with over 100k (107,000 to be exact). I'm changing my oil this week and was planning on switching to 10W-30 now.

would it be a smart move?

I'm currently using Mobile 1 synthetic.

Thanks

 

[RonJ]

100K miles? No need. The engine is still new. Stick with 5W-30.

 

[lethal6]

100K miles? No need. The engine is still new. Stick with 5W-30.

I agree. No need.

 

[young_]

When should the switch be done? I'm curious. I've ran 10w-30 on all my Hondas, though they were all above 160K

 

[lethal6]

Why switch at all? We put 0w40 in all the cars that come though the shop at work as that is what is recommended by Porsche. We don't change the weight just because of the mileage...

 

[young_]

Why switch at all? We put 0w40 in all the cars that come though the shop at work as that is what is recommended by Porsche. We don't change the weight just because of the mileage...

Makes sense. Just one of those urban legends I picked up along the way.

I've also heard to switch to a thicker oil if the motor leaks. I know it's obviously more logical to replace whatever gasket is leaking though.

 

[RonJ]

I know it's obviously more logical to replace whatever gasket is leaking though.

Yep

Leak = change gasket(s) or seal(s) or O-ring(s), not oil weight

 

[lethal6]

Makes sense. Just one of those urban legends I picked up along the way.

I've also heard to switch to a thicker oil if the motor leaks. I know it's obviously more logical to replace whatever gasket is leaking though.

Haven't heard that one before. So if the car is leaking, up the weight so it leaks thicker oil now? Only way that would actually work would be to up the weight thick enough to actually gum up the hole and that is not a good thing.

Only reason I see to up the weight would be places with extreme differences in climate temperature for different seasons or if running hot constantly on the track and the oil thins out. Oil lubricates stuff. No more or less lubrication for higher mileage. They still get lubricated the same.

 

[SpeedTechnik]

I agree with Ron and Lethal on this one...although I have heard the urban legend I think it's smarter to place in the recommended oil. Unless you move to a place with some type of extreme temperature change, I believe you have to accommodate for that by changing the consistency to achieve proper lubrication.

 

[Trekk]

I think it's an oil company training thing they tell the guys at the auto parts stores. I've had a decent amount of people ask me the same question. Normally it's after they go to buy oil, the guy at the counter tells them they should switch due to high mileage and larger clearances from wear.

 

[jameswanser]

I've been around a while, but have never heard that before. I can understand due to tight tolerances, wanting to use the thinnest recommended, but hadn't heard about upping the weight over time. Would only be guessing how much the parts have worn, possible that wouldn't lubricate as well as it should.

 

[cgpEJ6]

I don't agree with it but it's a very common theory, I can't believe you guys have never heard of this. When I worked in an oil change place, we got this request a lot.

 

[lethal6]

I have heard of upping the weight over time I just don't agree with it. The manuals don't say anything about upping the weight after time or mileage, just for different climate markets. What I hadn't heard about was increasing the weight to stop leaking.

 

[young_]

I have heard of upping the weight over time I just don't agree with it. The manuals don't say anything about upping the weight after time or mileage, just for different climate markets. What I hadn't heard about was increasing the weight to stop leaking.

Yeah, I'm from Georgia so we've got a lot of "DIY redneck mechanics".

 

[cuetip]

dont switch the oil at all civic love the 5-30 oil its not to thick, my grandpa used 10-30 in his car and he said it felt sluggish so he asked his mechanic and he told him to only use 5-30, so basically next oil change he used the 5-30 and he could feel a huge difference in reaction time

 

[lethal6]

dont switch the oil at all civic love the 5-30 oil its not to thick, my grandpa used 10-30 in his car and he said it felt sluggish so he asked his mechanic and he told him to only use 5-30, so basically next oil change he used the 5-30 and he could feel a huge difference in reaction time

I'm sorry but no, he didn't. Going from a 5w to a 10w just meant that the oil is very slightly thicker at start up. Has more to do with colder outside temperatures anyway. So if it wasn't -10 degrees out the difference more than likely wouldn't be felt at all.

The first number is the thickness during start up until it warms up and the second number is the thickness at higher temps. So maybe he had a slightly sluggish start up but it would have nothing to do with while it was actually running if he didn't change the weight of the second number.

 

[cuetip]

oh lol now i know lethal, i just use whatever it says on the cap

 

[ekprimal]

lol i totally forgot i posted this thread. Just thought about it today being that i'm now around 4k miles since my last oil change and the thought came into my head again about switching to thicker oil. thanks for all the replies guys. 5W-30 it is!!