Ok Guys , here is my situation,my brother drove my M923(NHC250),off road and went through some rough terrains and now tells me that when he engages the truck in 1-5 the truck ''jerks or drags'' until he puts back in 1-2 it drives fine and has the jerking issues when he puts the truck in reverse gear.. he tells me it almost feels like the truck has brakes engaged which lead him to checking for air leaks and came out short....Any help will surely be appreciated.