[officerholbrook]

Mobile ! 5w-30 and mopar filter from wallyworld. Although it apparently (according to the shop) ruined my new engine (rounded off two lobes of the cam and also ruined the lifters). Waiting till about 1500 miles till I make the switch from the regular stuff.

[southtxdstroyer]

mobil 5000 with a mopar filter
did my second oil change about a week ago

[Philly60]

I use Mobile 1 10w30 full synthetic had to use a Fram filter though...

[KentuckyTJ]

10w-30 Castrol GTX w/ Wix 51085 filter............can't be beat

[JDePietro]

After tearing apart engines for a year or so it seemed to me that the engines running a synthetic were at the very least the cleaner of those I have dealt with. To many variables to say without a doubt but that was one of the reasons I have used synthetic when its time for an oil change. Reason number two is it lasts longer. If you ever have a chance to measure the viscosity jump on it and compare syn with "other" after 3000 miles the difference is not vast but note worthy. For my rides Mobil 1 synthetic has been the ticket and with every other oil change I add a bottle of Lucas Synthetic oil treatment. After chaning my tranny fluid with Amsoil I am curious if their oil line is any better than Mobil, I sure did like how it smoothed out the 1st to 2nd shift.

I also use a K&N oil filter, and the only real reason for this is due to the magnet on the bottom. After my third oil change while using this combo I have found less and less shavings and grime in my oil.

Just my .02

[Jerry Bransford]

Originally Posted by JDePietro

... and with every other oil change I add a bottle of Lucas Synthetic oil treatment...

Check this link on Lucas out, which is just one of many reasons I will NEVER EVER add any additives to my engine oil. http://www.bobistheoilguy.com/images/lucas/lucas.htm

The vast majority of the additives are little more than kerosene or snake oil anyway.

[southtxdstroyer]

mobil 5000 is dino oil and is good for -you guessed it- 5000 miles or 6 months
plus its only $11 for a gallon at walmart

how does synthetic compare to that?

[JDePietro]

Thanks again Jerry for the informative link.

I have two sorta question(s)/critique(s).

If the Lucas oil foamed up as much as his test did wouldn't it start to come out of the valve cover or worse yet effect the emmisions? You would have to lose oil at a pretty ridiculous rate if that was the case. Of the many oil changes I have done to my Jeep I have yet to notice or see any discoloration that would indicate any sort of foaming and yes I have done them while the oil was still scalding hot.

Ratio makes a difference, I would not adivise nor add myself a whole case of Lucas straight. Mixing 5:1 or even 5 1/2:1/2 is what is recomended and what I follow.

All things said I have just changed my oil and am running just pure Mobil 1 10w30 and just for S&G I'll do it again next time.

[tjchuck]

Mobil-1 5W-30 full synthetic

[ArchStanton]

My Jeep had Amsoil and now has Penzoil 10-30 full synthetic with a Mobil 1 filter. I just bought three-oil-changes worth of Mobil 1 10-30 synthetic and Mobil 1 filters. Pep Boys has five quarts of Mobil 1 10-30 synthetic with a Mobil 1 filter for $30, which is a pretty good deal.

[Jeepster83]

ever since i was very little i remember my dad using Havoline non-synthetic engine oil. hes been a professional ASE certified master tech for years and he still uses it in his personal vehicles. and ever since ive had a vehicle of my own ive used nothing else. never had any problems and now my Jeep is on 6k miles and is due for another change. my Jeep gets 10w-30 every change.

[jweaver321]

Mobil 10w30

[jazzman31]

Royal Purple 5-30W and a Reusable Oil Filter.

Just wash the filter out after every 7,500miles.. I can run almost 12,000-13,000 miles between oil changes. Done the visocity test and with my oil filter its like the oil is brand new.

Oil never expires its what the oil gets went running through the engine that wears it out. If you can filter that oil then oil should last forever.

All in theory.

[Robert J. yates]

Originally Posted by Elwoodblues37

I just had my 4.0 rebuilt. I was told by the shop that falling zinc (zddp) levels in oils is
Killing motors with solid lifter cams. They recommended a racing oil with high zinc. Anyone else here anything on this.

Other than using racing oil (which I don't know what that means), your shop is correct.....see my post here:

http://www.jeepforum.com/forum/f9/ran-without-oil-help-830992-post7704840/#post7704840

FWIW...I use a good synthetic (Royal Purple 10w30) in my rig with a Comp Cams zinc additive. I used to run Rotella 15w40 which is a diesel formula but then they dropped the zinc content in it last year. That is when I switched to the RP and additive. I am also getting better milage with the 10w30.

[RJV]

10w-30 mobil1 syn w/ a mopar filter