My invoice show LL1030. And mine is a crew cab, can't see there being a difference in suspension though.

 

honestly man, i have only used my 4x4 maybe 5 times, each time it was just to get me from slipping and sliding on a 8' patch of soggy land for work

but i have not experienced any 4x4 problems... that is until i have posted this, now the damn thing probably wont work

 

lots of aftermarket options aswell Loads on ebay for $100! guys I did mine myself! works great! looks wayyyy better than stock!