I'm stating to wonder if I should sell my brand new 33'' grabbers and get a set of 35's instead.
Ah... scope creep... gotta love it.
Just remember why you bought it in the first place and see if it still fits that role. An IFS taco will never be a super capable rockcrawler. It is what it is, and trying to make it a big rockcrawler will just ruin what it does well, kill resale value, and make you want to get a dedicated crawler anyway (been there, done that, and still doing that). Imagine tipping your truck on its side and how mad you'd be. I'd be pretty ticked if I wrecked a truck that sweet. I'm not saying you shouldn't wheel it, just don't try to make it a super capable rockcrawler. A stock trd taco with sliders can do 90% of the trails in Moab. Ask yourself it you really need to go bigger to be able to do those other 10%.
Would I love it if you went to 35's? Absolutely! I think tacos on 35's look great, and tacos on 37's look even better, and I'd love to have a friend with a similarly built truck.
However, unless you're taking it out every few weeks, I think the responsible decision would be to keep it as is. If it were my truck, I'd try to lower it a bit. I'd remove the rear 1" block and go with softer front coils (since you don't have a winch or big bumper), and wheel it all over the place. It's plenty capable as is. 35's will make it tow worse, ride worse on the freeway, and will cost a lot of money that you'll never get back. Haha, even knowing all that, I'm still going to run 35's on mine, I'm such a hypocrite.
I've got the room for them. I just need to do a little trimming of the front of the rear flare. Will my truck hold up to 35's with the ifs or is there anything else I need to worth or think about? I'm already planning on regearing in the somewhat near future.
I hope I don't come across as a know-it-all. I'm just trying to offer some friendly advice. I'm interested in hearing what others say. I used to think I'd be able to clear 35's on my d-cab without major modifications. It seemed seem like all I needed to do was trim a little plastic, but without a body lift, I realized I had to do some MAJOR cutting. If your suspension was rigid, then you'd be ok. But once the a-arms flex up even a little bit, that 35" tire starts rubbing just about everywhere: washer bottle, frame (on steering lock), front of the inner fender, back of the front bumper, back of the wheel well, body mount, etc.
Imagine trying to fit 35's with no lift. A suspension lift isn't going to gain you any clearance. Once your bumpstops are maxed out in the front, your tire will be just as stuffed with no lift as with a 4" lift (unless you do a body lift or a lift that changes your A-arms). 35's rock, I love 'em, but it requires a LOT of cutting and re-welding to make them fit. Just be prepared to do that if you really do go to 35's.
Will my truck hold up to 35's with the ifs or is there anything else I need to worth or think about? I'm already planning on regearing in the somewhat near future.
If you take it easy and don't wheel like a leadfooted maniac, I think you'd be fine. I never had any problems with mine, but I do wheel like a grandpa, so take that into consideration. Knowing how you wheel, I think you'd be absolutely fine.