Originally Posted by Okiespaniels
Background: I have a 3 inch BDS AAL which is in an "offroad" spring pack which gives me almost 5 inches of lift over a stock ram. I use the factory block.
I have no issues with my driveshaft, although it does stick out of the tailshaft about 3/4 inch more than stock.
A 4 inch block will lift your rear axle about 2 inches.
I'm not a fan of taller blocks or stacking blocks. Because of the direction the pinion moves under acceleration (upward). Taller or stacked blocks create a longer leverage point. This can cause or increase axle wrap which can lead to wheel hop under accelleration and braking.
Add a leafs (AAL) while more difficult to install, bend your stock springs to create lift. While this can lead to a much firmer ride, it also avoids the pitfalls of blocks.
IMO..."long style" AALs are the best choice. Short AALs are way too stiff. They can cause spring damage and give a VERY harsh ride.
EDIT: Eventually your new front springs will settle enough to level out the truck.
Since my truck will probably only see pavement should I be that concerned about wheel hop and axle wrap? the reason for swapping out the front springs was because the previous owner had cut the originals and the lift coils were cheaper than stock replacements. It has settled about an inch already but still sits taller in front. I just want to level everything out or a slight front rake would be acceptable.