jon_solo

Yep. I had to pull the block and do 2" shackles to get it level.

So original measurements were 36.5F and 39.75R which led me to purchase a .25" replacement block, but turns out they were able to just remove the factory block and do the shackles which ended with 37F and 37.5R. I guess it pivots some when lowering the back which makes sense now that I think about it. I'll get some pics when it stops raining but it looks level to the naked eye, rides the same and improves the look for sure. It's a good use of $250 for parts and labor. Now if I could just find some reasonable color matched door handles and mirror caps in onyx black Parts department wants $350 for parts and $300 to paint.

Pretty sure to get to the 3" on the 6401 you have to remove the factory block and use the 2" setting on the shackles. The factory block though is more like 1.25" which is why I ordered a .25" replacement block. That should give me 3" total drop. I'll know a lot more around 1:00EST tomorrow so I'll follow up!

Looks good tony...new here also...I'm having mine done on Wednesday. Just picked up a 2016 SLT with the GMC 22s and it's measuring 36.5 in the front and 39.75 in the rear so I'm doing 2" shackles and swapping the factory block for an aluminum 1/4" block. I'll still have a 1/4" rake which shouldn't be noticeable over the length of the truck. The guys at the shop (who do a lot of trucks) swear I won't need any pinion angle shims so we'll see.