Ron Gratz wrote:
For 2008, the online manual reads:
3. Attach the trailer to the vehicle and adjust the hitch equalizers so that
the front bumper height is within 1?2” (13 mm) of the reference point.
After proper adjustment, the rear bumper should be no higher than in
Step 2.
This reasonably could be interpreted as an acceptable range of:
minus 1/2" to plus 1/2" with a midrange of 0"
or
0" to plus 1/2" with a midrange of 1/4".
In either case, a measured height increase of 1/2" would be at the extreme end of the range.
Since I've seen no indication that Ford considers their 2011 specification to be retroactive to 2008, I would shoot for a front-end rise of not more than 1/4".
Better yet, you might want to contact Ford's technical department to see what they have to say. It's always good to get an "official" opinion.
Ron
Today, I hitched up using Ford's recommendation of zero lift on rear and plus or minus 1/2 inch on front.
What I got was plus 1/2 on front and minus 3/4 on the back. According to Ford owners manual, this is within range.
Then, I went to a place that sells hitches, went over the numbers with them, and was told "no amount of lift on front is good, they don't care what the owners manual says".