Best oil for 7.3L?

[Hades212]

I use Royal Purple in mine, but mostly because of the abuse and intermittent service she gets, I figure it gives me a bit of a buffer. Or I could be completely wrong

[Ditty]

I use good 'ol Shell Rotela 15-40. I work at Jiffy Lube right now so I get 50% off!!! No more $83.53 oil changes. And I get to top off the leaker all the time which is nice if you have a 7.3, b/c they do tend to leak.

We do have Penn Synth Blend 15-40 that I was thinking about trying on my next change since I'm due. We also have Rotela Full Synth 5-40 that a lot of diesel customers swear by.

Really and truly though, as long as your consistent with changing the oil AND oil filter...your good no matter what you use.

[scagmanf350]

I like rotella but its all personal preference

[bigb56]

Originally Posted by Ghillie

Agrees with supercruty: Any of the top named dino oils will work-->Delo-Rotella-Mobil Delvac.-->All 15W-40. If you live in a colder region, ya might think about pouring in a synthetic 5W-40 yr round. If ya use the dino 15W-40? Don't go past 5K miles between your Oil change. If ya use the 5W-40 synthetic? You might beable to go to within the 5K to 10K mile mark without a by-pass system installed. Make sure too use a good oil filter... like
Motorcraft FL-1995
Fleetguard LF-3630
Wix 51734
Baldwin B7039
Mobil 1 M1-601
Amsoil Ea0-99

Clean oil plays a major part in keeping your 7.3L running like new... Never skimp on a cheap oil filter.

My International dealer sold me a LF9027, I hope it's the right one! Is it a good filter?

[TWHRanch]

I use Valvoline SynPower 5-40W with WIX or Napa Gold Filters. (Napa Gold Filters are WIX filters)

I have been using nothing but SynPower 5-40W for the last 10 years or so due having a mixed fleet of gas and diesel engines. It's one of the few oils that exceeds all current service requirements of both gas and diesel engines. I also double the normal service interval. Example 5,000 miles becomes 10,000 miles and 50 hours becomes 100 hours between oil changes. The extended service intervals help off sets the higher cost of synthetic.

Only having to buy one oil for all engines sure simplifies servicing all the cars, trucks and tractors around the place.

[builtnotbought]

I have always use Esso XD3 and never had any problem at all

[choctaw]

Originally Posted by Ditty

I use good 'ol Shell Rotela 15-40. I work at Jiffy Lube right now so I get 50% off!!! No more $83.53 oil changes. And I get to top off the leaker all the time which is nice if you have a 7.3, b/c they do tend to leak.

We do have Penn Synth Blend 15-40 that I was thinking about trying on my next change since I'm due. We also have Rotela Full Synth 5-40 that a lot of diesel customers swear by.

Really and truly though, as long as your consistent with changing the oil AND oil filter...your good no matter what you use.

Bingo..............enough said.

[2003_F250_FX4]

I use 14Qts of Rotella 15-40 with 1Qt of Lucas Oil Treatment with a K&N Oil Filter

I change mine about every 5-7K my truck sees alot of highway miles and 5K comes very quick. If i am going to do a long haul tow I will change the oil no matter how long it have been

[dmd]

Also.... Have the oil tested for the driving you do. Just because someone can go 10k
on the oil doesnt mean that you can. Contaminates and the HPOP in every 7.3 kill oil. It is very
rare to find any truck that can go over 5-6k before the oil needs changing using test results.

Just because the bottle says you can run it twice as long, it may not be true in your
engine. If running a bypass filter, intervals can usually be extended much longer.

Use a name brand oil, get it tested, change as often as the tests say so.

I change at 5k because that is where the Delo in my engine starts to break down and
the contaminates start heading up.

[groundpounder]

I just got off the phone with those Blackstone Lab guys and boy, they are a helpful outfit! Sending me a test kit as we speak. Good stuff