Hey, sorry for the thread necromancy here but heck, it was the first google result I got so I'll stick with it!
First of all, I love your ideas, and I love that you want to play Tryndamere tankier. I think that's a great idea that most people overlook entirely because they feel that his ult negates any need for survivability (I happen to disagree vehemently). Trinity force in particular is a bit of a favorite of mine when I'm playing him--massive props to you!
Now here's what I disagree with, and there are a few things:
One: no armor penetration. I mean, none whatsoever. You trippin'? I mean, Tryndamere still does damage without it, but getting absolutely no ArPen in items OR runes seems to be a pretty big mistake. Remember that your spin does physical damage despite being boosted by its 1:1 AP ratio, and in order to get as many trinity procs as you can, you're going to want to be spinning constantly, utilizing the wonderful CDR provided by crits. Perhaps if you were a 3000-health, 200-armor/MR tanky monstrosity, you'd be contributing enough off-tanking power to the team that you could get away with this, but as it is I think you need to reconsider (if you haven't already). Personally, I like to solve this little problem with ArPen reds and a ghostblade. Ghostblade is an incredible item on Tryndamere! AD, crit chance, CDR, ArPen, and ASPD/MV from its beautiful little active--what's not to love? The components are cheap too, and an avarice blade can help you get through those painful early games. Personally, I get it instead of an atma's impaler along with armor masteries and flat armor seals, which together with wriggle's lantern add up to a very solid ~120 armor.
Two: wit's end is a great item and all, but I think it's a mistake to get it instead of maw of malmortius. Maw scales with lower health, synergizing wonderfully with bloodlust and undying rage, its damage works with critical strikes and lifesteal (not an unforgivable weakness for wit's end, but a noticeable strength for maw), and most importantly it protects you from what I feel are Tryn's biggest weaknesses: burst so high that you don't have time to activate your ult (GO AWAY LEBLANC/POPPY), and long-range finishers like Karthus or potentially Ezreal. Considering your goals with this build, I'm pretty puzzled that you didn't go for the maw!
Three: finally, I'm a bit puzzled that you didn't at least mention the cleanse spell. No, it's not the most game-breakingly powerful spell, but its main function on Tryndamere remains mostly untouched: getting rid of well-timed ignite that someone on the enemy team placed on you at the end of your ult. Bloodlust will heal 300 health with 100 fury at level 18, or 345 if you have a t-force--ignite will do a total of 410 damage without even considering that it will halve your healing from lifesteal and bloodlust, and it will ignore the shield from maw if you have that. It's not absolutely vital, but it's still game-changing on him. Plus, it gives you the option of getting berserker's greaves, which are a very noticeable boost when your only other ASPD item is t-force (unless you get wit's end, but I still think that's a mistake), especially in his early game.
Stuff for non-OP posters: PD is a kickass item and all, but zeal already covers a lot of PD's functions, and you don't particularly need to upgrade it for quite some time after you buy. In the meantime, trinity force effectively doubles his CC, adds a chunk of HP and a not-insignificant boost to his healing (if you're building him with zero survivability you're playing against stupider players than I see regularly), and adds a proc that is a lot more spammable than you think (if you get at least one crit per second, his spin effectively has a 3-second cooldown). By the time I feel ready to upgrade zeal to PD, I'd much rather have grabbed a phage in the meantime and spend ~1600 on trinity than on PD. It's the same movement boost, 5% less crit, 25% less ASPD, 30 AP (+30 damage to your spin, +45 healing to your bloodlust), 12 AD (cool), 25 HP (whatever), and the two procs that are wonderful on Tryndamere. The sheer amount of utility is perfect for him.