Marley77

Yeah I actually have...on a 12" lifted super duty. Talked to the guys at synergy and teraflex said I should be fine for quite some time.

Maertz

a 2010 shouldnt require any exhaust mods... 4" is not TON of lift.... IMO its a pretty good lift height... Also just cutting fenders does nothing for travel if you dont set bumps correctly and have longer travel shocks, a 4" lift and non cut fenders could travel way more depending on setup.

roscoj

You will be good with that lift. I think around 4" is a great size. It's what I run. Talk to synergy and make sure you get shocks and bumpstops set accordingly.
Keep in mind you can't add the trackbar bracket in the front if you don't do the flipped drag link so it's either a fliped draglink with trackbar bracket or an adjustable front trackbar if you want the axle centered.
Your drive shaft will likly last a while. You never know. Mine lasted 35000 miles on my 2009. I wheel fairly often. You might as well get your use out of it.

PhxSilver

It will only travel until it hits the flairs and rubs them until the clips fail and your flairs are hanging loose. I see no point in putting a 4" lift on and then putting a huge amount of bump stop to stop the up travel. Unless you are building a Mall Crawler.

Maertz

im sorry i will take your advice in the future....