28 in 400Lb Gas Struts SF280M400 - Heavy-Duty Lift Support

In this review the ARANA 28 in 400Lb gas struts are evaluated for owners of very heavy trailer lids and sled trailer covers. The bottom line: these struts are designed specifically for lids weighing roughly 350-440 lb and deliver the lifting force and length needed for large, heavy-duty applications. The reviewer found them noticeably stronger than standard lift supports, and the 28 in extended length and 16 in compressed length make them a direct fit where long travel is required. Expect straightforward installation and firm, reliable hold when matched to the correct lid weight.

Key Features

• 400 lb force per strut: Provides the high lifting power needed to support heavy lids in the 350-440 lb range so lifting and holding are easier.
• 28 in extended length: The 28 in center-to-center extended length gives long travel and clearance for tall or deep trailer lids and tonneau covers.
• 16 in compressed length: The 16 in compressed length lets you confirm fitment with limited mounting space and ensures correct stroke for the lid.
• 13 mm ball sockets: Standard ball socket ends simplify mounting to common trailer caps and replacement brackets without custom adapters.
• Set of two: Supplied as a matched pair so both sides of a lid operate evenly and deliver consistent support and balance.
• 18 month replacement support: Manufacturer support and replacement help is available for missing parts or fit issues, giving buyers added confidence after installation.

Who It's For

This product is best for owners of heavy-duty trailer lids, sled trailers, snowmobile trailer covers, or truck caps that require long struts and high lift force. Installers replacing worn or weaker supports on lids with a side length near 50 in and an estimated lid weight between 350 and 440 lb will find these struts match the requirements.

Those with lighter lids, small hatchbacks, or applications under the stated weight range should look for lower-force or shorter struts instead. Also verify your OEM number or measure the lid weight before buying, because the strength of these units is excessive for smaller covers and could alter closing feel.

Pros & Cons

Pros

• High force rating gives reliable lift and firm holding on very heavy lids.
• Long 28 in extended length fits long-travel applications like trailer caps and tonneau covers.
• Easy installation with 13 mm ball sockets and a matched pair reduces setup time.
• Clear manufacturer support and 18 month replacement policy for parts or fit problems.

Cons

• Not suitable for lighter lids; must confirm lid weight or OEM number to avoid incorrect fit.
• Some customers report mixed long-term durability, so occasional premature failure is possible in heavy-use scenarios.

Specifications

Extended Length (center-to-center)	28 in (711 mm)
Compressed Length (center-to-center)	16 in (406 mm)
Force per Strut	1780 N / 400 lb
Socket Size	13 mm ball sockets
Quantity	2 struts per pair
Compatible OEM Number	SF280M400
Intended Lid Weight	350-440 lb (approximate)

Our Verdict

These 28 in 400 lb gas struts are a sensible choice when replacing or upgrading supports for very heavy trailer lids and covers; they deliver the stroke length and lifting force required and arrive as a matched pair for balanced operation. Buyers should measure lid weight or confirm the OEM number before purchase, but when matched correctly the units represent solid value and practical support backed by replacement assistance.

Frequently Asked Questions

Will these struts fit my trailer lid?
They fit lids that match the stated geometry and weight: 28 in extended, 16 in compressed, and lid weight roughly 350-440 lb; check your OEM number SF280M400 or measure the lid weight.

How hard are they to install?
Installation is straightforward with the 13 mm ball sockets and typically takes only a few minutes per side once mounting points are confirmed.

What if a part is missing or they do not fit?
The manufacturer offers help and 18 month replacement support if parts are missing or the struts prove unfit when ARANA is contacted.