Jeep Strokers

I'm especially interested in 5w40 synthetic motor oils. What is your favorite and why?

How many people think choice of oil doesn't matter?

It matters. Valvoline VR-1 10w-30 is what I use.

Valvoline VR1 10w30

VR1 doesn't have the additive packages for normal oil change intervals.

Brad Penn 10w30

And yes, it does matter. It matters a great deal.

jsawduste wrote:VR1 doesn't have the additive packages for normal oil change intervals.

Brad Penn 10w30

And yes, it does matter. It matters a great deal.

^^^^ This

Everything seems to happen in California first and usually for the worse. Between six months and a year back many of the oil's got reformulated. Valvoline was one of them.

I'd have more confidence in the smaller independent oil companies like the previously mentioned Brad Penn.
Surprisingly they're not that much more expensive and at least list the additives in their bottles that we know others are taking out

VR1 got reformulated?

No, same stuff they sold for years.

It's a good oil for it's intended purpose. Typical Jeep operation falls out of the purpose.

10-30 VR1 for the last 79k miles.. Including break in. Works well for me.

jsawduste wrote:VR1 doesn't have the additive packages for normal oil change intervals.

Brad Penn 10w30

And yes, it does matter. It matters a great deal.

I called Valvolive. They said VR1 has enough addatives for a 3000 mile oil change interval. My current 4.0 has 181,000 miles. I bought it with 52,000 miles. I've only used VR1 since I bought it. I changed the valve cover gasket a few miles ago, the inside was clean as new. My engine runs smooth and quiet with 181k miles

SkylinesSuck wrote:VR1 got reformulated?

A friend of mine that owns a small independent auto parts store had all of his Valvoline oil recalled and replaced about a year back. The reason wasn't to change the looks of the bottle but was to change what was inside the bottle.

Rotella went through a similar change.

Re if choice of oil for Jeep 4L.

I think choice of oil matters too. However, you'd be amazed how many people at various Jeep forums tell me the Jeep 4 liter engine works well with any oil. One smarty pants even told me that it would work fine with grape juice as a way of emphasizing his opinion that choice of oil doesn't matter.

Even half the guys at Bob is the oil guy forum told me that choice of oil doesn't matter for a Jeep 4 liter. I don't get that way of thinking because that forum is about oil choices. If choices don't matter then why does that oil forum exist?

So I figured I'd ask Jeep stroker guys. You all probably know more about Jeep 4 liter engines than any other forum, and probably know more about oil for it.

Oils I'm interested in and considering using:

T6 Rotella 5W40

Chevron Delo 5W40

Chevron Supreme 5W40 (Is this a Euro oil?)

Valvoline Synpower 5W40 (Is this a Euro oil?)

Valvoline Maxlife High Mileage 5W40. This oil allegedly exists, but I haven't seen it. Maybe it's only available in Europe?

Pennzoil Platinum Euro 5W40. This is the oil I've been using lately. I think it's a good oil, but it's expensive.

Mobil One Turbo Diesel 5W40. I used to use this oil. I think it's a good oil, but it's expensive.

I change my motor oil every 5000 miles, which seems reasonable since my driving is half city and half highway. However, I don't drive much. My oil gets changed approx every 2.5 years.

Why do you prefer 5w-40? The thinnest oil they yields the required pressure is best (kinda).

I used Brad Penn 10w30 for the first 50k(SAE-30 for the cam break-in and first 600mi), but for a couple years now have been using Rotella T6 in it and in my '95 M3(unless Mobil 1 is on sale). I did notice the new bottle this last time. . .

I don't like the idea of running real light oils in engines that do not have real tight bearing clearances. In a newer style engine that has .0005" bearing clearance a zero weight oil (when cold) is desirable. Not so much in a something that has around .002" clearance which is about where the 4.0's should be set For this reason i would stay away from anything starting with a zero or 5 and gravitate towards a 10w or 15w cold rating.

Running diesel oil is a thing of the past. They took all the good stuff out years ago.


I use Joe Gibbs BR30 break in oil for the first 500 miles. It is NOT street legal because it has all the good stuff in it and is specially formulated for engine break in utilizing flat tappet cams.

After that I use Joe Gibbs HR __ W - __ which is also NOT street legal because it has all the good stuff in it. The offer a 15w-50 and 10w-30 and 10w-40 oil ALL IN A HIGH ZINC FORMULA THAT IS COMPATIBLE WITH A FLAT TAPPET CAM.

At some point well after the rings are seated I will change to Mobil 1

The NASCAR boys are running spring loads in excess of 500lbs over the nose on a welded flat tappet cam. Joe Gibbs hired lubrication engineers and addressed the problems associated with those kind of spring loads on a flat tappet cam. The oil formulations and additive packages are designed specifically for a flat tappet cam engine.