i since i bought my truck and started researching, as it was the first IFS rig i've owned, all i've heard is "just crank"..."those keys are a waste of money".......now, i'm admittedly not experienced with these trucks........but......cranking the stock keys adds more "twist" to the torsion bars, subsequently raising the front up, at the same time.....right? the raising of the truck is only a side effect of torsional twist.....more tension EQUATES to more height.....height+tension=more height OR height-tension=less height.
not only does it ride worse because of the geometry, but because the bars are "maxed" in the torque they can produce, after all they're a spring.......a torsional spring. twist it, it wants to twist back. if it can't twist back, it raises the truck....that's physics, no getting around that.
now if you use a "lift key", it changes the percentage of the fulcrum's advantage, no? so the "stock" AMOUNT of twist on the bar will raise the truck the same as if it was at the stock height......the torsion bar doesn't give a **** what the height of the truck is, all it knows is that it wants to spring back to it's natural relaxed shape.....it doesn't WANT to be twisted.
the indexed key would then raise the truck just like the stock keys does, only it would HAVE to provide a better ride as the torque on the bars required is NOT as great........at least that's MY understanding of the physics behind lift -keys. of course you'll have accelerated wear an tear on front suspension components as they're not operating in their designed(read neutral)parameters....the angles are more severe, downward travel is definitely impeded etc, etc, etc........longer brake lines, shocks...perhaps a new upper control arm with better ball joint? it depends how well you want to build it.....or over build it.
i'll TRY to articulate what my 2 brain cells are thinking.....i believe they're on the same page today.
picture 2 clock faces, with the hour and minute hands welded together as on piece..think "<"...one clock reads 1:15, the other reads 2:15......if you pushed UP,(counter clockwise) on the MINUTE hands of both clocks, which HOUR hand will reach the 12 first? the second clock's minute hand will HAVE to travel further to get it's hour hand to 12.......more travel equates to more torque in my "twisted" analogy.
forgive me if i "explained" this in these simple terms, but that's how my little mind works...not EVERYONE understands the principle behind torsion bars.....i hope this helps.
the AAL will make the rear ride worse than stock as it ADDS more tension to the spring pack.....for 2"of lift i'd do a block and keep my stock ride.....unless your springs are ****, then it may actually help.......any lift i would do, i'd prefer new COMPLETE spring pack... no blocks or AAL's......but axle wrap shouldn't be a huge issue at 2"....all my lifts were 2 "-3" on my K/5's(except my first Rancho kit)....dummies will add HUGE blocks to get lift for big tires....these are the same people that won't re-gear for the change either....axle wrap is a REAL thing. there's physics to that too....but that's a topic for another discussion.
like i said, this makes sense to ME.....if someone can explain how this is NOT true, i'd be happy to entertain the "argument". i don't know everything, just what make some sense to my semi-mechanically oriented mind.
the keys are NOT so much about height as it's about ride quality.
kennythewelderOfficially Retired, B31-3 (6-G) certified welder.