question open to anyone researching this...i have been told by numerous sources, 3" is max on these trucks with stock parts...2.5" is much safer.
but how does a simple drop of the dif correct what all is truely wrong?????
the control arm ball joint angles (lowers at 3" plus), get maxed to say the least...how are these companies expressing that a 4" is fine on stock parts without control arm drops and longer knuckles ???
i dont see it, even a correctly fabbed upper arm with high angle joints doesnt address the lower arm joint angles.
i am still leaning towards a simple 2.5/1.5 level lift or full blown 4" plus with all drops incorporated.
Definitely a valid point on the lower control arms and ball joints, they are not addressed in any leveling or "budget" kits that don't have replacement knuckles and dropped cross members like a 4" BDS or 6" kit. My 2 cents is that the lower ball joints, based on the angles, are more forgiving than the uppers to the angle change. Below is a pic of mine with the 2.5" and stock UCA's. The upper ball joint you can tell isn't right based on the way the boot looks, but the lower doesn't look too out of whack. Upper ball joint failures seem to get the spotlight, lowers don't seem to be mentioned much. Under-reported, or harder to notice when they fail perhaps, or the geometry just has more forgiveness.
The other thing that isn't addressed with these is tie rod angles. On my previous F-150 6" pro comp I'm pretty sure there was either spacers for the steering rack to drop it a bit and/or the connection point to the knuckle was higher. As I've mentioned here and there, the full blown 6" lift came with it's own challenges for me anyway. With that said, the 4" BDS looks like a very nice kit.
For the 2.5/1.5 you're considering. I would have nothing negative to say on the 2.5 front. If you have stamped UCA's seems many have made a case to replace those ASAP with any level because of ball joints popping out of the UCA's. For the 1.5 in the rear, only comment, my 1" rear went in fine but I get a clunk occasionally back there on hard right turns. I'm wondering if there's something relating to the sway bar end links or shocks since things are slightly stretched. Could be just mine and the 1.5 will be fine for you, just throwing that out there. Maybe you'd do rear shock extensions as well with the 1.5.
My biggest concern at the moment, and this would be with any lift that drops the front diff, is that it will change the angle slightly on the front driveshaft. I do drive in auto and 4HI on the highway at times, so hoping I won't pick up any vibration. On the F-150 with the 6" I had to pull the front driveshaft, re-clock and have it balanced due to vibration. Fingers crossed that won't come into play with the 4/3 readylift.
