My initial thought was that you might be pushing, even possibly exceeding, the weight limits of the Pilot..., but then again I don't know your loading habits.
Here are some items that ran through my mind when I read your post:
* The published tow rating of 4,500lbs for your Pilot unfortunately doesn't represent your "actual" tow rating, this thread will explain: http://www.jaycoowners.com/showthread.php?t=3866
* Think in terms of "loaded weights", not UVW or dry weights. Loaded weights will represent real life towing conditions.
* Check for the actual "ship weight" that is noted on the X20E's yellow weight sticker (UVW is 3,610lbs per Jayco web site). This may add another 100lbs - 250lbs to the published UVW weight (depends on Jayco model).
* I would add another 600lbs - 800lbs to the ship weight to reflect the added weights of the WDH, battery, cargo, and stuff (no fluid in tanks)......, the added weight is based on "my" loading habits if I owned an X20E.
Hypothetical scenario: Assuming the "actual" tow rating of your Pilot is 4,100lbs, and lets assume the loaded X20E is (3,610 + 100 + 600) = 4,310lbs, so this assumption would tell us that we are exceeding the Pilot's tow rating. The GVWR of the X20E is 4,750lbs.
Just some food for thought.