Ive never had problems driving them straight enough to suit me. But then, I don’t much care what the white folks downtown think.

Go to Home Depot and pick up the best fence builder waiting for a job and you can have a cold beverage while their working, they always seem to be straighter when someone else is driving them

Put in 2 end posts about 70 or 80 yards apart. Stretch a line, not wire, tightly between them. Start the posts on the line. If anyone smarts off, hand them the post driver. BTW, put the posts on the ground, where you want them, in advance.

After all the advice I got here on how to drive em straight, the next one I drove leaned to the right, just like the last bunch. I think Ol Thumper probably has the best advice.

I use this and push them in with my tractor bucket.

https://www.amazon.com/Swanson-Tool-PL001M-Magnetic-Level

I've got one and I don't care who calls me a sissy. Best investment we have made out at the lease. It weighs about 45 lbs and it takes less than 20 seconds to get a post in through limestone 6" down. We can do a 12 panel pen in less than 2 hours from pulling up to drinking the beer and looking at the pen all set. Highly recommend them, and I"d suggest buying one over renting if you need to do more posts.

Mine is a Titan with a Honda motor....works like a charm

Looks like a great machine, but not something I’d ever need. I have all the fence I need, with most of it being good, so my T-post driving doesn’t happen too often, and only when a gap needs repair or a tree crushes some fence. Of course, I did drive some t-posts for firewood stacks, and they all leaned. If it wasn’t for cows, I wouldn’t even need fences, and I don’t own a cow. Life in the country.