This seems IMHO a little heavy for Texas in the Winter! If you were looking at a month of 100+ temps and a lot of idling (?) or sustained really high speeds in the Summer.... well, maybe?
The 15W-40 suggestion for year-round is probably a very good one. I know, I know! Those who are now dealing with -20 & wind chill can't believe it! Some of us do live in milder climates and don't have to deal with cars frozen solid, etc.
Pennzoil's LongLife is cheap, available almost anywhere, has a terrific base formulation, a top-shelf additive package including Moly, and will do a lot in keeping your engine clean internally. Delo's good, too.
'91 420 SEL @ 199K, '92 SVX @ 181K, '93 SC400 @ 86K, '93 Kaw ZX-11 @ 30K, '87 F250 @ 181K , 2001 Valkyrie Interstate @ 6K, Y2K Honda NightHawk 250 with 1.5K, '88 420SEL I.@ 179K & the 2nd latest, an '88 420SEL II.@ 210K runnin' parts car, '85 F150 300/NP435