You are probably already at the rear GAWR limit. A good reason it has a tag.
For Rear Lifts have your front & rear axle weighted when loaded for travel. Then you can add on the extra weight of a lift by below.
Measure the distance from the center of rear axle to the center of the weight(Lift)
Divide that number by the RV’s wheelbase.
Multiply the result by 100 to get percent.
That percent of the load is added to the load and becomes the total load added to the rear axle.
That percent of the load is subtracted from the front axle weight and unloads the front axle by that amount.
800 lb bike, Lift 100 lb=900 lb
Center axle to rear 120” wheelbase 240”
120 divide by 240=0.50 X 100= 50%
Weight is 1350 lb added to rear axle
Front axle will be 450 lbs lighter
99 Discovery 34Q ISB
2014 MKS AWD EcoBoost Toad
Fulltime Since "99"