Sumit
The Unit TON is US ton (also called Short Ton) the conversion of which is 907.18474 kg
You need to use a Unit which is equal to 1000 kgs
In my system it is TO (See the picture below of 'Mass' units in tcode CUNI ).
If you do not have such Unit, you need to create one, where the detail screen would look this way.
Then use TO in place of TON in Fleet master.
Secondly, you have to go with the KG unit in IE36.