Best oil for Florida? Stroken 7.3

[Deuces Wild]

03 7.3 with 127k miles. Mainly highway driving, pull a boat front time to time just wanted to see what everyone else was running and figure out what would be the best oil for 100+ degree days

[rufushusky]

Well what are you planning for oil change intervals, if it is under 7500 miles any conventional oil will work just fine..

IMHO in balmy Florida any CJ-4 15w40 will take very good care of you. It won't get near cold enough for a 5w40 to be even close to necessary. I mean you can run 5w40s if you want but I just don't see any benefit to the significant additional cost.

I like Delo and Delvac in my 7.3 but Shell, Castrol, Valvoline etc all make a good 15w40.

[Deuces Wild]

I've never ran synthetic in anything I've even owned, but I always do my oil when it's needed, and no problems ever from fords to dirtbikes. This is my second 7.3 and I want her to last forever, so should I go with a synthetic or keep doin what I'm doin?

[rufushusky]

Personally, I would just keep doing what your doing. Run a good CJ-4 oil and change it on a regular basis...your engine will out last your truck.

[85_305]

I put synthetic into everything... motor, trans, diffs etc.

[rascal]

I just changed oil with Amsoil 15W-40 CI-4+ for pre-2007 diesel engines.

I also have a bunch of Royal Purple Synchromax I am about to use in my ZF-6 and transfer case. Just waiting till I can order the DieselSite transmission filter.
Also have RP 75W-90 waiting to go in diffs as well.

In short, synthetic in everything for me as well.