Jeep 3.7L engine - dirty oil

[high_rpm]

I recently bought an '05 Grand Cherokee with the 3.7L engine. I changed the oil about 1,000 miles ago, at 37k. It's a little over 38k now, and the oil looks pretty dirty on the dipstick. At the last fill, I dropped in what I had at home - a few quarts of Quaker State and a few quarts of Motorcraft semi-synthetic. In comparison, my minivan which I've owned for years has 95k miles, and still shows relatively clean oil when I check it at the 1,000 mile interval after its last oil change.

I'd like to clean up the engine a little, but I don't want to spend $28 for a 5 quart jug of the Mobil 1 at Wal Mart on the next oil change. I'm leaning toward the Motorcraft semi-synthetic which is dirt cheap, or maybe even that Supertech Synthetic oil. And 5k mile OCI.

Do you think these oils will clean out my motor with time?

 

[Nickdfresh]

If you want to use an oil to clean, and I know you don't want to spend too much, but Pennzoil Platinum 5w30 makes a cleaning claims as does Mobil 1 10w30HM...

But Valvoline MaxLife might be your best bet which is what I initially used as I changed oil on my Ectotech 2.2L that was absolutely FILTHY when I got it. Firstly, I topped off the oil with one quart of conventional 5w30, and used a bottle of CD2 Oil Detergent (YB) drove for a few hundred miles. Then I dumped the puked oil for a 3KOCI of ML 10w30 blend. It was fairly dirty at the 3K mark. I then used Pennzoil Platinum 5w30 over the winter and the oil is now reasonably clean after three months in the engine and over 3K...

 

[addyguy]

At only 37k, I doubt the engine is that dirty inside. I'd be inclined to just do a few short 2-3k drains of regular conventional oil, maybe with Rislone or MMO in them, and then go to whatever you want. Motorcraft is an excellent oil for 5k OCI's.

 

[rg200amp]

I'd run a quality synthetic like Pennzoil Platnium.

 

[ViragoBry]

Don't make the mistake of going by color to judge an oils cleanliness or lack thereof. My 2006 Mazdaspeed 6 (syn since 2500 miles, 3000 mile OCI) and my 2005 Ford Sport Trac (syn sense 3000 miles, 3000 mile OCI) darken the Pennzoil Platinum at different rates. Both engines are spotless inside, but the Sport Trac darkens the oil faster than the Mazda. I can only assume this is due to heat, although I can't imagine why the Ford 4.0 would run hotter than the Mazda 2.3 Turbo.

Sorry to ramble. Just be aware that color isn't necessarily an indication of an oil's cleanliness.

 

[demarpaint]

Originally Posted By: addyguy
At only 37k, I doubt the engine is that dirty inside. I'd be inclined to just do a few short 2-3k drains of regular conventional oil, maybe with Rislone or MMO in them, and then go to whatever you want. Motorcraft is an excellent oil for 5k OCI's.


+1, and the color of the oil really doesn't mean much.

 

[Nickdfresh]

For the most part, I agree with that.

I'd personally use Penn Platinum 5w30 and monitor closely. Any good conventional would be okay too, and you could think about using something like Rislone or CD2 if you didn't want to spend on ARX or something...

And I also second the Motorcraft suggestion...

 

[StevieC]

Originally Posted By: high_rpm
I recently bought an '05 Grand Cherokee with the 3.7L engine. I changed the oil about 1,000 miles ago, at 37k. It's a little over 38k now, and the oil looks pretty dirty on the dipstick. At the last fill, I dropped in what I had at home - a few quarts of Quaker State and a few quarts of Motorcraft semi-synthetic. In comparison, my minivan which I've owned for years has 95k miles, and still shows relatively clean oil when I check it at the 1,000 mile interval after its last oil change.

I'd like to clean up the engine a little, but I don't want to spend $28 for a 5 quart jug of the Mobil 1 at Wal Mart on the next oil change. I'm leaning toward the Motorcraft semi-synthetic which is dirt cheap, or maybe even that Supertech Synthetic oil. And 5k mile OCI.

Do you think these oils will clean out my motor with time?