DRUMMACHINE666

the oil cap says i need to put 5w20 my jeep has 118,000 miles n i bought 5w30 high milage mobile 1 oil ....my question is would it make a difference? is it safe to use on my jeep? i read somewere that the 5w30 is just thicker oil just not sure

jagrover

To me, there is such a small difference that the 5w-30 will not matter. I have used from 5w-20 to 20w-50 in my old Jag and it hasn't noticed one bit. If you are happy with the 5w-30 then use it. I use a super synthetic 5w-20 in my Jeep cause that's what I get free at work. The reason behind the 5w-20 is during the emissions testing, different weights of oil produce different emissions. The certification for the lowest emissions uses 5w-20 in testing. This is not to say that changing to 5w-30 will turn on the engine light, which it won't, but just the manufacturer getting the engine emissions certified.

Go ahead and use the 5w-30, it won't hurt a thing.

-Mark

DRUMMACHINE666

sweet thanx man makes me feel better lol

yo_marc

Yes!, feel free to use it!

Been running 5w30 for about a year and a half now. Probably about 40K miles. Currently at 123K miles.

The motor runs a lot quieter. I felt a small decrease in power up at highway speeds, but it's not bad (and I'm a mpg-stickler). May not be noticeable if you are running heavy tires and lots of mods.

Jeff Loughlin

I've always used 5w30. Most manufacturers are recommending 5w20 on newer vehicles because of CAFE fuel efficiency standards, and from their perspective the extra 0.25 mpg that 5w20 might provide makes a difference. But also consider that from their perspective your engine only needs to last until the warranty expires, so what they recommend isn't necessarily what's best for your engine. Go with the 30. It's a little heavier and will provide better protection.

Ryan0260

These motors do better with 5w30, or 10w30, especially if it consumes oil

JK-Ford

Been using the manufacturers spec motor oil since my 07 was brand new. I live in an area that sees triple digit summers and single digit winters. No oil issues at 100K miles.

wharris_jr

Use the diffent oil should be no big deal - ever think about using AMSOIL - they say you only change once a year but iti s pricey.

Enzo

I agree

Jiblet

Remember that the weights of oils are representative of viscosity ranges and are not absolute, especially across brands.

One brand's 5W-20 could possible be nearly identically viscous compared to a different brand's 5W-30 when both are at operating temperature. Or they both could be at opposite ends of the spectrum, with one brand being closer to 10 and the other closer to 40.

That's true even between different batches of one brand oil.

So simply comparing the numbers without considering the brand and formulation really isn't informative. Especially when comparing synthetic to conventional based oils.