I changed my oil this morning and switched to 15w-50. There is additional language on the bottle about additional protection and being race approved which is not on any other grade of Mobil1 oil. So far oil temps are about 2-3 degrees cooler. By the way, Walmart by me is doing rollback pricing right now. I paid 19.94 per 5 gallon jug. Can't beat that!!!

I changed my oil this morning and switched to 15w-50. There is additional language on the bottle about additional protection and being race approved which is not on any other grade of Mobil1 oil. So far oil temps are about 2-3 degrees cooler. By the way, Walmart by me is doing rollback pricing right now. I paid 19.94 per 5 gallon jug. Can't beat that!!!


I'm right there with you.
I'm just waiting for my Rig to turn 6 G's.
That's right I said 6 BigOnes.:D


Has anyone seen O/40 Mobil 1 at WalMart in the 5 quart container?

Is everyone one Cool with running the 5/15 Mobil 1 During the summer with City driving???

T:cool:

Switched at my first oil change (600 miles).....every 3k after that.........about to do the third.

I'm right there with you.
I'm just waiting for my Rig to turn 6 G's.
That's right I said 6 BigOnes.:D


Has anyone seen O/40 Mobil 1 at WalMart in the 5 quart container?

Is everyone one Cool with running the 5/15 Mobil 1 During the summer with City driving???

T:cool:

Awesome. Love the picture. I'm gonna try to put my 2 1/4 ton jack in the house (like you) and see if my wife likes it.

I have not seen the 0w-40 in the 5 gallon containers either. Don't think it's available.

I changed my oil this morning and switched to 15w-50.

There goes your warranty............:eek:

There goes your warranty............:eek:

Yeah........ok.....:rolleyes:

There goes your warranty............:eek:

Not true. The SRT Engineers have been quoted saying 15w-50 is acceptable. In fact it's part of a TSB on the same motor in the LX cars. No warranty issue. They only use 0w-40 out of the factory cause it can cold crank down to every temperature (climate) they distribute the Jeep SRT8 to.

Does everyone think using 15w-50 is ok during north eastern winters?

There goes your warranty............:eek:
Check the TSB's. In fact the engineers also stated it is the only oil they would use for racing and that Mobil 1 recommends.

From what I understand, the SAE oil rating simply means that the oil has a viscocity relative to that of 15-weight standard oil during "winter" start-up conditions, and has a weight of 50-weight standard oil during normal operations.

The 0-weight oil would simply be beneficial to extreme cold where its necessary for it to flow easier before the engine warms up.

Does everyone think using 15w-50 is ok during north eastern winters?

Someone please correct me if I'm wrong but I believe 15w-50 is good down to 0 degrees F.

As soon as I got mine home 23,000 miles ago I drained that 0wt......and refilled with 15-50

Obviously didnt hurt a thing.....if anything wear was below normal.

http://i77.photobucket.com/albums/j66/sgtstanko/Oilanalysis11.jpg

http://i77.photobucket.com/albums/j66/sgtstanko/Oilanalysis12.jpg

maybe I have been in the AZ sun to long, but doesn't the heavier oil use more engine power ( loss of hp) and would it not effect in a small way your gas mileage ?

The 15-50 probably provides a little more protection under extreme conditions in hot weather, but will flow slower in cold engines and in cold weather climates. I would bet that it will also increase drag on the engine a tad, but probably not significantly once warmed up in our JEEPs.

As for me, I'm sticking with the 0W-40, it will flow better at startup, has a lot of long life additives, is used by Mercedes in all their AMG products, and should definitely be better for those Winter months.

Well said, the flow with startup's is important. I would go with 0w-40

I've been running 15W-50 for about 1500 miles down in Texas per the TSB about the noise from the oil squirters "fluttering". Outside temps are in the mid 90s now, and rising, plus the noise happens rarely. I'll probably change back to 0W-40 when it cools down in late November or December.

I've been running 15W-50 for about 1500 miles down in Texas per the TSB about the noise from the oil squirters "fluttering". Outside temps are in the mid 90s now, and rising, plus the noise happens rarely. I'll probably change back to 0W-40 when it cools down in late November or December.

That is my plan also.

I park in a non- heated parking garage but never get's too cold or hot. How long should you let your Jeep warm up before putting it in gear and driving? I'm trying to wait at least til the autochoke returns the RPM to 800 or so. (20 to 30 sec.)

If I'm running late, turn over place in drive.

That can't be good.

T:cool:

maybe I have been in the AZ sun to long, but doesn't the heavier oil use more engine power ( loss of hp) and would it not effect in a small way your gas mileage ?

Here is the thread confirming 15w-50 is OK in the Jeep SRT-8 and is best for racing. If it's used in racing, that tells me it means better protection and no loss of engine power. Regarding the gas, at this point, what's the difference, mpg is so low already. But so far I have seen no difference.

http://www.cherokeesrt8.com/forums/showthread.php?t=4377&highlight=15w-50+SRT

From the Mobil1 site. Thought some of you might be interested.

"Mobil 1 15W-50 is being reintroduced based on popular demand. Mobil 1 15W-50 provides higher viscosity, designed to provide extra protection for performance vehicles and vehicles that operate in severe service, such as towing, hauling and racing. Additionally, Mobil 1 15W-50 contains higher levels of anti-wear (ZDDP or Zinc DialkylDithioPhosphate) that may be required for certain racing applications and camshaft designs. This is a new Mobil 1 15W-50 formulation and is not the same as the product that was marketed a few years ago."

Is 0w-40 what these trucks come stock with?

Is 0w-40 what these trucks come stock with?
Yes......................................

Yes......................................
Thanks......................................

Since this thread was brought back to life. Here is some additional information about using 15w-50 in the winter. Mobil1 15w-50 can be used safely in temperatures down to -29 deg C (or -20 deg F). I researched this and the rule of thumb is 10 deg above the lowest pour point. The pour point is -39 deg C on this oil. I live in NJ so I'm OK to use this all year round.

Typical Properties Mobil 1 15W-50
SAE Grade 15W-50
Viscosity, ASTM D 445
cSt @ 40º C 131.2
cSt @ 100º C 18.1
Viscosity Index, ASTM D 2270 154
Sulfated Ash, wt%, ASTM D 874 1.21
HTHS Viscosity, mPa•s @ 150ºC ASTM D 4683 4.50
Pour Point, ºC, ASTM D 97 -39
Flash Point, ºC, ASTM D 92 235
Density @15º C kg/l, ASTM D 4052 0.87