[DK on the road]

I have access to a truck scale. I know this is not the preferred way to measure axle weights. I can confirm that its not, by the facts below. My confusion comes from the switch on my dash that says "tag axle" and the light that says "Dcres weight" or something like that.  While checking axles on the scale, I left only the 3rd axle on the scale, the drive and steer were off the scale. 

with out the "tag axle" switch I read #17,140
with the "tag axle" swicthed and the light reading "dcres weight" I get #20,760

why ?

has somebody mis wired my switch ?

#20,760 seem too much on the tag axle.

Back to the scale, it is not level going off one of the ends, so I choose the better end of the 2 to measure from. Also as I park the front axle on with tag and drive axles just off the end. I get different reading from going on the scale from a different direction. In other words, trying to get as close to the middle of a 80' scale. #20,800 facing west, #18,900 facing east.

Totals for Going west
Steer only                    #20,800
steer and drive only      #43,240
All 3 axles                    #57,070
drive and tag only         #37,920
Tag only not measures because the ramp going off would add weight to the Tag.

Totals for going east 
Steer only                   #18,900
Steer and Drive only    #32,740     (ramp or bump at this end may throw this measurement off)
all 3 axles                   #57,460
Drive and tag only       #39,380
Tag down (?) #17,140
Tag Up (?)     #20,760

 Are scales not accurate when not loaded evenly across the "plate" ?  Crappy scale ?


It's has to be the scales....partially. Right?

I want the correct weights, Where have you folks found to get this accurate information

Thoughts????