Can the Jack Back Onside support my jumbo RV trailer?
Yes! The OnSide uses reinforced steel equivalent to a solid 1″ × 3½” bar, providing maximum strength. Its design minimizes leverage on the tongue weight, ensuring stable and safe support for even large trailers.
Why does the OnSide have a unique shape?
The bold, eye-catching shape is not just for looks—it’s engineered for strength and efficiency. Its design maximizes stability while sparking curiosity wherever it’s seen.
Should I mount the OnSide inside or outside the trailer frame?
Mounting inside is often better because it:
Keeps the jack out of the way of operators
Avoids conflicts with RV weight distribution or sway bars
Provides more mounting flexibility in tight spaces
Moves the jack closer to the trailer center for better balance
You actually have 12 mounting options total for maximum flexibility.
How do I choose between OnSide and OnTop?
OnSide: Requires only 10″ of frame space, allows dual jacks for ultimate stability, and can use affordable electric jacks with backup safety.
OnTop: Mimics traditional center mounting, may feel more balanced for RVs or horse trailers, and can carry additional equipment like propane tanks or batteries.
Tip: Two OnSides are generally more stable than one OnTop.
What propane tank sizes work with Propane Lock?
Propane Lock fits any pair of same-size tanks on standard double racks, whether or not mounted on a Jack Back. It secures the tank hold-down mechanism for safety and theft prevention.
What size batteries fit on the Battery Platform 1408?
The 1408 platform supports any battery group, type, or size. Batteries just need to be securely bolted—even if they slightly overhang the platform.
Can I add a second battery without disturbing the first?
Yes! Jack Back offers multiple ways to expand trailer battery capacity:
Add a second battery on a Battery Platform 1408
Install OnSide, OnTop, or Side-to-Side jacks with Battery Platform
Use OnTop Maxi to mount one or two batteries
Use Side-to-Side Maxi for flexible battery placement
Attach a plywood platform with our Shackle Kit to bolt on battery boxes
How can I use the plywood triangle from the Shackle Kit?
Step or reach higher when hitching
Work surface for tools, pins, or tow bars
Base for a small storage box for chains or tools
WORKS WITH THESE TRAILERS
UTILITY
CAR
BOX
HORSE
CARGO
BOAT
RV
ATV
FLAT BED
DIRT BIKE