We will look forward to pics of the rig, and some driving reports.
I imagine you've already seen this one, still, I believe it the best preparation:
http://www.airforums.com/forums/f238...-in-17984.html
Test drive X5 over to the nearest CAT Scale: full fuel, driver and otherwise empty. If time, use sides of scale to get right or left side off of pads and acquire all four individual wheel weights on second & third re-weigh (about $10, then $2 each followup).
As to " a few runs", when I installed the Hensley Arrow on my diesel Dodge and 34' Silver Streak (at about 6,900-lbs that day; truck at 7,400-lbs) I got out on I-20 west of Fort Worth and did full throttle-on, slammin' lane changes from shoulder to median strip and back across the Interstate at 55 mph. Couldn't shake it loose at all.
Would have gotten the Pro Pride (better weight-distribution fine tuning) but, alas, it came out a few months later.
I assume your trailer will have disc brakes? A sway-eliminating hitch and disc brakes is the gold standard, IMO. Many of us are also happy with CENTRAMATIC balancers.
Am much interested in mpg at various speeds on any turbodiesel rig.
Thanks.
.