That's an interesting way of thinking of it.
So, by this definition, ground clearance is simply the distance between the ground and the lowest point on the rig? Like the diff?
I have a 6" suspension lift on my E350 (a ujor lift I installed myself). While the lowest point of the vehicle (the diff) wasn't raised with this lift, everything else was. I gained all sorts of ground clearance everywhere except the axles: my rockers, frame, rear bumper, trans crossmember, fuel tank, etc. all have 6" more ground clearance than before the lift. Suspension lifts don't just make room for bigger tires, they also raise the rest of the vehicle, which gives you more ground clearance all over. The lowest point of the van is still the same distance from the ground, but there's more ground clearance on 99% of the van. I'd gladly take an extra 2" of clearance at the rocker panels than at the lowest point (the diff).
I hope this doesn't come off as confrontational, I don't want to argue. I've just never heard of ground clearance being explained this way, and I'm trying to understand what people mean when they say the 2" quigley lift gives no extra ground clearance.If they're saying that the lowest point (diff) is still the lowest point after the lift, then I agree. That's true of all lifts. However, there's tons more ground clearance everywhere else, which is why I'm confused. I haven't looked at the quigley lift in enough detail to know exactly how the lift is done (blocks in the rear? New leaf springs? Bigger shackles? Longer coils up front? Spacers? Stiffer springs?). However, I assume that the roof, rockers, belly, bumpers, and everything except the rear axle and the front control arms sit 2" higher. Is that correct?
I've been wheeling and lifting 4x4 rigs for years, and the last thing I hit is the diff, because I put my wheels on top of the obstacle, rather than straddling them. So to me, the minimum ground clearance at diff is far less important than the distance of the rockers and at the bumpers and the belly from the ground.
Last edited by sixstringsteve; 09-09-2016 at 07:21:PM.