Hi hope someone maybe able to help. The other day i was trying to reverse a car trailer with a car on up our drive. The 1st part of the drive has a small incline and the rangerover was in low box reverse, i had nearly got the trailer to the top of the incline when the car refused to go any further backwards. i had to unload the car off the trailer before the range would continue to move backwards. I want to know if this is a terminal problem that will require a box change. The gearbox is not the origional but was 2nd hand, however i did put a brand new torque converter in. It moves fine in the forward gear but even unloaded it seems sluggish and a bit unwilling in reverse. Any advice would be greatly appreciated.