0W-30 GC in a '06 Jeep Wrangler LJ 4/0L I6 Engine

[GoHack]

Hi,

I just bought an '06 Jeep Wrangler Unlimited (LJ), w/the 4.0L I6 engine.

I had some 0W-30 GC lying around, so I changed the oil using it, together w/a NAPA oil filter. The Jeep's owner's manual says to use 10W-30, so should I have any problems using the 0W-30 GC in it?

For it's normal operating temperature, it's still a 30 weight. Actually, from what I've read, it's a heavy 30 weigh, being more like between a 30 and 40. So would the 0W vs. the 10W, be a problem, especially here in the northwest?

The GC also is an ACI Service SL oil, which because of it's higher Zinc content, should be better for the 4.0L engine than the newer SM or SN, which have less.

I've read that people like using M1 High Mileage, because of it's high Zinc content, so how does it compare to the GC?

Thx

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[KCJeep]

That should be real good for you in the 4.0, in fact it's on my list to try one of these days. Like you said it's a thick 30 so it's a great match. I've been running the Castrol HM 5w30 which is also a very thick 30 and I've been very happy with it.

I've seen at least one UOA with Castrol 0w30 in the 4.0 and it looked very good wear wise, just as you'd expect.

Nothing wrong with higher ZDDP but the 4.0 doesn't really seem to need it once broken in. I've spent countless hours perusing 4.0 UOA's and higher ZDDP doesn't seem to make a lick of difference in wear numbers either.

 

[Kuato]

Use with confidence; I've been using 0w30 or 5w30 year round with good results.

Steer clear of M1 0w30 though; using that oil with the flat tappets resulted in more than twice the iron found in the UOA over any other oil I tested.

 

[GoHack]

Thanks for your responses.

So the fact that it's a 0W-30 or 5W-30, vs. the Jeep's manual's recommended 10W-30, shouldn't do any harm to my engine?

Thanks


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[KCJeep]

Originally Posted By: GoHack
Thanks for your responses.

So the fact that it's a 0W-30 or 5W-30, vs. the Jeep's manual's recommended 10W-30, shouldn't do any harm to my engine?

Thanks


.


Nope, none at all as long as it stays a true 30 grade at operating temp. You need to watch 5w30's as they can be more prone to shear down to a 20 which is less than ideal, but so can any 30. The 10w30's as a group are less prone to shear and the 0w30 you're talking about is a particularly thick 30 of high quality as well, you're good.

I've got my Castrol HM blended down to a standard 5w30 for winter, but would want something thicker the rest of the year. The Castrol 5w30 HM straight (when I haven't intentionally thinned it) is thicker than most 10w30's thus part of the reason for my affinity to it. The Castrol 0w30 you mentioned is thicker still, good stuff.

 

[afoulk]

shouldn't cause you any problems. Infact, these engines seem to really like Rotella T6 5w-40, so running a heavy 30weight oil should be no problem at all. These things seem to run on pretty much anything though, from PYB or VWB 5w-30, up to Rotellat T 15w-40.

 

[GoHack]

Again thanks for all your responses. If I want an intelligent conversation about lubrication, or anything else, this is the place to come , as opposed to a Jeep forum, where all they say to do and use, is what the manual says, and nothing else, and don't waste your money on synthetic oil, or use other weight oils. I've encountered some pretty rude people there when you try to do any kind of discussion w/them about the issue.

I like to take care of my vehicles. I've always had the belief that if you take care of your vehicle, keep it maintained and serviced, it'll take care of you, especially in places where you don't want to break down, like offroad. On top of having it checked out, I've gone and replaced ALL the fluids in the entire powertrain on this LJ, a tune-up, filters changed, greased, and tires check balanced and rotated. I've also run Seafoam through the fuel system, and I use only Top Tier Detergent Fuels, using mainly Chevron w/it's Techron in it, on all my vehicles.

This LJ is in excellent condition, 100% stock from the factory, but these vehicles are not very fuel efficient, as everyone here knows. Today I went and filled up, calculating what my mileage was, and it came out to be 17.35 mpg, using the winter grade of gasoline, which is the best that I've gotten so far, which is great for a Jeep, especially w/the [censored] winter grade of fuel we are stuck with, this time of the year.

The only mods that I have in mind are first, installing a locking hub kit, which from my own experience doing it in the past on another vehicle, gained me between two to three miles per gallon. Of course it may never pay for itself, but it does means less wear and tear on the powertrain, as well as the vehicle handles and drives better on the highway w/the front axle and driveshaft totally dis-engaged. I may also consider the installation of a locking differential in the front as well, a Spartan Locker, since the axle will be disassembled anyway. The rear has a Trac-Loc Limited Slip. Next, some less aggressive tires for the summer, and finally, a winch. No suspension lift kit or bigger wheels and tires.

This Jeep is my second vehicle, for weekend offroading, camping, and winter driving. When offroading, other than logging roads, good and bad, w/some washed out, I don't do any hard offroading.


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[KCJeep]

Yes a discussion about oil on something like Jeep Forum will be an eye opener to just how many old wive's tales are alive and well.

Sounds like you are completely on the right track to me.