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Which Engine oil do you use??

7K views 78 replies 54 participants last post by  acharrier 
#1 ·
Hi Guys,

I have 2003 Rubi - 29,000 miles on it. Is anyone using synthetic oil in their engine? What weight of oil are you using? I am in Southern CA - Hot Hot Hot so cold morning starts are not an issue here. I wheel in the desert - slow stuff and some city traffic.
 
#4 · (Edited)
When I bought my Wrangler I did a lot of research on what oil/filter to run. Previously on my XJ I was using Valvoline MaxLife oil with a Fram Tough Guard oil filter.

Update: I no longer run Mobile 1 10w30 and will be switching to a 10w30 with ACEA A3 ratings after reading "My oil is killing my engine!" thread.

I eventually decided on Mobile 1 10w-30 full synthetic paired with a K&N Performance Gold oil filter(The 1" nut on the filter makes oil changes easy. I also like that K&N uses an anti-drainback valve). This is for a 2006 Wrangler Unlimited with 32,000 miles on it.
 
#5 ·
I run Valvoline (dino) 10W-30. And in 45 years of driving and using nothing but dino oil changed every 5K miles, I've never had an engine failure.

Personally, I wouldn't pay extra for synthetic except during the winter if I lived somewhere like Buffalo NY or North Dakota where it gets cold enough to take advantage of synthetic's better cold weather flow. Synthetic is certainly not the miracle lubricant many think it is. Heck there's a guy over on JU whose 2.5L engine just crashed and burned after only 111,000 miles and he had run nothing but synthetic oil in it since it was new.

Check that thread out at I need to vent a little -
 
#9 ·
I run Valvoline (dino) 10W-30. And in 45 years of driving and using nothing but dino oil changed every 5K miles, I've never had an engine failure.

Personally, I wouldn't pay extra for synthetic except during the winter if I lived somewhere like Buffalo NY or North Dakota where it gets cold enough to take advantage of synthetic's better cold weather flow. Synthetic is certainly not the miracle lubricant many think it is. Heck there's a guy over on JU whose 4.0L engine just crashed and burned after only 111,000 miles and he had run nothing but synthetic oil in it since it was new.

Check that thread out at I need to vent a little -
Jerry, the OP in the link you posted had a 4banger that went TU, not the 4.0 I6.

To answer the original question, I use Valvoline Synpower 10w30 in all my vehicles. Always have.
 
#8 ·
You have a 2003 with very few miles on it. I personally would run synthetic in your case. I run dino in mine and typically tell everyone else to do the same. Since you are not putting anywhere near 3000 miles in three months synthetic may save you money. The synthetic would have a 12 month shelf life inside the motor.
 
#10 ·
I know a lot of people think synthetics are great and all, but:

Your jeep engine was designed and tested using conventional oil, it has never been tested with synthetics that I know of.

So, if it was designed and tested to last 150k miles + on cheap oil, why would you spend all that money on synthetics?

I think maybe BMW and a couple of others actually design and test with synthetics but not jeep.
 
#12 ·
Here comes the oil debate again. Conventional Valvoline 10W-30 is in the pan right now, but I might change to Rotella since it's heavy in zinc and I have a source for it that can save me a dollar a quart below retail.
 
#15 ·
Cheapest 10w30 here as well. About to break 200k and the engine still sounds as smooth as rocks in a dishpan.
 
#16 ·
10w-30 synthetic here, I noticed an immediate improvement in gas mileage when I started using it when the engine had about 70k miles on her, now up to 190k and engine still runs great. I take several weekend trips to the mountains during the winter so extreme cold starts are common for meh. Despite the comments above, I can get 5 quarts of the stuff for about $6 more than non-synthetic @ WalMart, that's really not that much more and I feel more comfortable letting her go 5-6k between oil changes instead of 3-4k like I used to do, so it is actually cheaper. I hear you can do 8k+ in a 12 month period if you really want to live on the edge. :)
 
#19 ·
I run Chevron Delo 15W-40 oil in my 4.0. Can't beat 1300 ppm of Zinc and 1200 ppm of Phosphorus for $10 a gallon. That and a Mobil One oil filter.

I've tired several oils in my 4.0 and the Delo by far gives the lowest levels of metals in the oil on a used oil analysis.



FOG
 
#21 ·
I run Chevron Delo 15W-40 oil in my 4.0. Can't beat 1300 ppm of Zinc and 1200 ppm of Phosphorus for $10 a gallon. That and a Mobil One oil filter.

I've tired several oils in my 4.0 and the Delo by far gives the lowest levels of metals in the oil on a used oil analysis.

FOG
I used to run Rotella T in that weight until they reduced the ZDDP content. Are you sure the Delo still sports it? That weight is typically spec'd for diesels and those levels of ZDDP are DPF killers.

Nice sig BTW :rofl:
 
#22 ·
I live in Michigan so it's Valvoline 10w-30 dino in the summer and Valvoline 5w-30 dino in the winter with STP S8A oil filter for extended capacity on all three of my 4.0L's. I also change the filter with every oil change.

99 xj - 252,500 miles (every 5,000)
03 wj - 176,000 miles (every 5,000-6,000)
97 tj - 119,000 miles (every 3,000)

Like FL 4.0L I also purchase the Valvoline at Wal-mart. A 5 qt. jug there is the same price as a 4 qt. jug at AutoZone/Pep Boys/etc.
 
#26 ·
What do you guys think about penzoil 10W 30? Ive been using that for the past couple years. I like it but i never hear anyone use it.
Pennzoil earned a bad reputation for sludge years ago so not many have forgotten it. But that problem went away something like 15 years ago when they went to their PureBase product that dropped the use of paraffin that was the cause of the previous sludge problem. With that long-ago change to their base, their engine oil has been as good as anyone's for many years now.

I'd run Pennzoil without a second thought if I couldn't buy Valvoline any more. :)
 
#25 ·
Personally, I don't have any problems with Penzoil. People debate the particulars and the minutiae of oil on a constant basis...and for me, the bottom line is this: they all work well when used properly. I've run Penzoil before and never noticed any problems from it.

I can't say much about the 2.5, but the 4.0 was designed in an era when our cheapest, most crap-tastic oils would have been considered state of the art. It's a very tolerant beast...as are most engines. Thus, I believe that dino oil, a good filter (I've even used Fram and never killed an engine...my stars!), and changing both regularly will serve you well.
 
#27 ·
that makes me feel a lot better Jerry!! thanks!! I plan on trying out Valvoline during my next oil change to see how much of a difference it is. I have also heard good reviews on the Napa Gold Oil filters. Do you have any experience with them?
 
#28 ·
I have also heard good reviews on the Napa Gold Oil filters. Do you have any experience with them?
I use them and love them. They're just a Wix filter, which is a very good filter. My LJ is very happy with Valvoline 10W-30 Dino and the Napa gold filter. I also ran that oil and filter on my TJ before it got totaled and it gave me 180k trouble free miles.
 
#29 ·
Swapping from one good major brand of engine oil to another good major brand of engine oil isn't going to produce results you will notice. Those that claim they immediately noticed better mpg, power, etc. by changing to some particular brand or type of motor oil are just victims of the Placebo Effect.

I don't know for sure who makes NAPA oil filters but I believe they are made for NAPA by Wix which is a very good brand of oil filter. Personally, I stick with either Purolator PureOne or AC-Delco Duraguard oil filters but Wix is among the "good" brands that are good to use. :)
 
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