Optimal oil for lethally cold weather, Jeep 4.0L, parked outside

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Minnesota
I'm fairly sure it gets much colder here than pretty much anywhere in Indiana. The vast majority of people still get dino 5w30 from oil change shops in their older cars and there is no mass exodus of vehicles as soon as we hit -30. Worry about the battery, less about the oil.
 
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Massachusetts
There's nothing especially cold about South Bend compared to any other Northern state. My Aunt and Uncle lived there for a while and we'd visit at different times of the year. The difference for you is that you're not used to it.

Historically, Mobil 1 products bring out some noise in AMC/Jeep 2.5L, 4.0L, and 258's. There was talk all over the Jeep forums and even here about it before the JK / JL days.

Chevron 5W30 was on sale at Walmart for $8 +/- a jug. It's a syn blend and it's going into my Wrangler's 2.5L very soon. It would work well in your Renix motor for South Bend winters.
 
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Danville, Indiana
There's nothing especially cold about South Bend compared to any other Northern state. My Aunt and Uncle lived there for a while and we'd visit at different times of the year. The difference for you is that you're not used to it.

Historically, Mobil 1 products bring out some noise in AMC/Jeep 2.5L, 4.0L, and 258's. There was talk all over the Jeep forums and even here about it before the JK / JL days.

Chevron 5W30 was on sale at Walmart for $8 +/- a jug. It's a syn blend and it's going into my Wrangler's 2.5L very soon. It would work well in your Renix motor for South Bend winters.
I've heard many say that about the noise in Mobil 1's in Jeeps and other vehicles, but I think that is all in people's heads. I've had plenty of Jeeps and the only time I ever heard more noise with Mobil 1 was when using Mobil 1 filters on my 3.8. For some reason the anti-drainback valves leaked at the particular filter angle in that engine and you'd get cold start rattle. So I switched at the time to Motorcraft and then later to Fram. Problem solved. Otherwise, the engines run as smooth as on anything else. That includes Jeep 2.5, 4.7, 3.8, 3.6 and 2.4 engines.

I'd run Mobil 1 EP 5w30, or EP HM 5w30, which is what I run in my 4.7. It'll keep that engine nice and clean and has a very low pour point due to some PAO content.
 
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Mahzurrah!
Mobil makes fantastic oil but Mobil 1 and the Jeep in line 6 don't historically do well together. Countless UOA's with Jeep 4.0's and 5x the iron numbers of any other oil. People will correctly say you can't judge wear by a 20 dollar UOA, but since no other oil does this and Mobil does it over and over again its pretty simple just not to use Mobil in that engine.

While your temps are not especially cold, they are plenty cold enough and the Jeep 4.0 can be a little cranky when the temps dip. It's also an engine that does better on slightly thicker oils, so in my world the perfect solution for you is a good Euro 0w30, 5w30/40 or 0w40.

Castrol 0w30 or 0w40 (lots of PAO base) and a bit more ZDDP for your flat tappets would be great choices.
 
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Someone needs to drive up to Edmonton, Alberta. Cold in Indiana? :ROFLMAO: 5w30 is just fine. Welcome to Bitog.:)
I went to Edmonton in the winter. I've never experienced cold like that before or since. Never saw electric outlets for every spot in a parking lot before.
 
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When I moved from CA to the midwest, I used to get all dramatic about the cold and snow too. Then I realized CA was a special case and more of the nation experienced this as a norm than I ever imagined. This past February we (along with much of the country) experienced unseasonably cold winter weather and it put things into better perspective. We had several days of double digit negatives when normally we'd be in the teens or 20s.

5w should be fine, but 0w won't hurt either. Some say you get a higher quality base oil in 0w, and that's what I go with personally in my vehicles that specify 5w-20. Our other vehicle already specifies 0w-20. If your engine normally specs 10w-30, then I can't see how switching to 0w-30 would be at all bad.
 
Joined
Oct 23, 2005
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Mobil makes fantastic oil but Mobil 1 and the Jeep in line 6 don't historically do well together. Countless UOA's with Jeep 4.0's and 5x the iron numbers of any other oil. People will correctly say you can't judge wear by a 20 dollar UOA, but since no other oil does this and Mobil does it over and over again its pretty simple just not to use Mobil in that engine.

While your temps are not especially cold, they are plenty cold enough and the Jeep 4.0 can be a little cranky when the temps dip. It's also an engine that does better on slightly thicker oils, so in my world the perfect solution for you is a good Euro 0w30, 5w30/40 or 0w40.

Castrol 0w30 or 0w40 (lots of PAO base) and a bit more ZDDP for your flat tappets would be great choices.
Spot on KC, thanks for bringing that up. Forgot to mention the "Jeep 4.0 hates M1" earlier.

OP I will post up my UOAs to show this if you like, but 10+years back this was well known.
 

Titanium

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Thanks guys. Lots to talk about. On the whole "that ain't cold" theme, know that 90° F is cool and breezy to me, especially if it's during summer. I was in Tempe, AZ for several years, which is slightly hotter than Tucson, and the average low/high in January is 39/69. South Bend is 17/31, which I wouldn't have thought was habitable for mammals. The high is below freezing. I can't wait to see the heating bills.

So several of you mentioned engine block heaters. I don't know anything about those. What powers them? Someone mentioned never seeing outlets at every parking spot until they went to Canada or Minnesota or something. There won't be room in the garage for the Jeep, so it's the odd man out. Will I have to run an extension to power a block heater? I assume they're electric, and not some chemical reaction warming pack, since those probably wouldn't last long enough.

This reminds me of a battery issue I was thinking about. It's not going to be my daily driver, so I want to use a battery tender or similar. But they all seem to need to be plugged into wall power. How do people use them for vehicles parked outside? I've searched for "portable battery tender" or "standalone battery tender", but I haven't had any luck. My visual here is a battery-powered battery tender, which seems super doable. Lots of compact battery designs and types could work for just trickle charging a car battery for a few weeks at a time. People on other boards got hung up on the assumption that a battery tender has to be plugged into wall power, or else where is the juice coming from? The answer is that it can simply come from a battery. I might try to just make my own. Have you seen any products? (I wonder if it's even possible for a battery to tend itself, if you could basically harvest or divert some of the drain right back to the terminals – it would still be a net loss over time, but it could be a big reduction in the drain rate depending on how the math hashes out.)
 

Titanium

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I'd be worried more about the battery.
How would you handle that? Are Optimas good for extreme cold? I've been seeing mixed reviews lately. People are upset at how they moved the plant to Mexico, and some are saying the quality dropped. I don't know of any primo batteries other than Optima.
 
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Any oil with a 5W winter rating at any starting temperature above about -30F is just as pumpable as one with a 0W rating. The OP's starting temperatures are neither lethal nor extreme. The whole thread is based on a premise that isn't an issue at all as long as an oil with a proper winter rating is used. That's the point of the rating.

And winter ratings are independent of the brand, the base oil composition and feelings.
 
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Another good thing to have in a cold climate is a jumper pack incase your battery dies, keep it inside at night and bring it with you durring the day.
 
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Someone needs to drive up to Edmonton, Alberta. Cold in Indiana? :ROFLMAO: 5w30 is just fine. Welcome to Bitog.:)
The poster needs to live in Interior Alaska for a winter, or actually work and drive the Dalton Highway way above the Arctic Circle a winter or three! In these areas, -20 degs F is a quite NORMAL daily temperature, and -35 and -45 degs F temps are not uncommon.

Indiana is banana-belt country!

Any syn 5W-30 oil will work in the Jeep, though some will work better than others (as talked about above). If the engine has way over 100,000 miles, you may consider a 0W-40 or 5W-40 oil.

Believe it or not, I know this stretch of Dalton Highway tundra. It lies about half-way between Alyeska Pump Stations #5 and #6, north of the Yukon River:
Dalton Highway.JPG

Winter blowing snows in this area make it difficult to see the roadway (it sort of disappears). You need to have an "eagle eye" and good judgement. I've traveled 25,000 miles between the Prudhoe Bay, Kuparuk, and Alpine Oil Fields, to include Trans-Alaska Pipeline Pump Station #1 in the north and Pump Station #6 near the Yukon River in the south.

When it's -20 degs F, like pictured here, the 100% snow and ice covered road has PLENTY of traction! It's just not slippery when it's THAT cold. We all drove sipped tires anyway.

Oh, the Dalton Highway is PURPOSELY iced over with water trucks come winter in the arctic! Purposefully! Why? Because gravel is flung by the 18-wheelers, taking out windshields of other passing trucks during the few warmer months! It's a narrow gravel road. Moreover, the ice helps to keep the gravel road in-place, if you catch my drift.

This gravel highway is "the" lifeline to the great northern Alaska oil and gas fields! These fields and the Trans-Alaska Pipeline System have supplied a rough average 1 million barrels of oil per day over the last many decades.

:)
 
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