Quick answer: the round rubber bumpers on most cargo and enclosed trailer ramp doors are 3-3/16" in diameter and 1-1/4" tall, mounted through a 3/8" center hole. To replace one, measure the old bumper's diameter, height and bolt hole, unbolt it, and bolt the new one in the same place with the old or new 3/8" hardware. Our 3-3/16 x 1-1/4 inch ramp door bumper is sold singly, in a 4-pack, and in bulk cases for trailer builders and dealers.
What ramp door bumpers do
On an enclosed or cargo trailer, the rear ramp door closes against the trailer frame. Rubber bumpers at the contact points stop metal hitting metal. That cuts the bang when the door closes, reduces rattle on the road, and protects paint and the door skin. Worn, cracked or missing bumpers are a common cause of a rattling ramp door.
Bumper size and specifications
| Specification | Value |
|---|---|
| Diameter | 3-3/16" |
| Height | 1-1/4" |
| Mounting hole | 3/8" (bolt or lag screw, not included) |
| Material | Solid SBR rubber, 60-65 durometer, black, non-marking |
| Sold as | Single bumper, 4-pack, or bulk case |
Specifications are from our product listings. If your old bumper is a different size, measure it as shown below. Our rubber feet size chart lists every other diameter and height we carry.
How to measure your old bumper
- Diameter: measure across the widest part of the bumper. A worn bumper may have mushroomed, so measure the base.
- Height: measure from the mounting surface to the top. Compare with an unworn bumper on the same door if one is left, because worn bumpers are shorter.
- Bolt hole: measure the diameter of the bolt or the hole it passes through. 3/8" hardware is common on this size.
- Count: note how many bumpers the door uses and where, so the door closes evenly.
How to replace a ramp door bumper
- Support the ramp door so it can't drop while you work.
- Remove the old bolt or screw and the remains of the old bumper. Clean the mounting surface.
- Check the bolt for rust or stretched threads and replace it if needed. You need a bolt long enough to pass through the bumper's recessed mounting hole and the frame or door, plus the nut.
- Set the new bumper in place and fit the bolt through the center hole. Tighten until the bumper is held firmly. Don't overtighten, as crushing the rubber shortens its life.
- Close the door and check that it meets every bumper evenly. Replacing bumpers in matching sets keeps the door sitting level.
Buying in bulk? Case pricing.
Need hundreds or thousands of trailer bumpers for a production run, a fleet or a resale shelf? Our most-stocked sizes come in case packs at a lower price per piece than single pieces, and we quote larger quantities on request.
Trailer manufacturers, dealers and repair shops use this bumper on every ramp door they build or service. Case packs bring the price per bumper down well below the single price. See bulk case pricing or ask for a quote for pallet quantities.
Other uses for the same bumper
The same 3-3/16" x 1-1/4" bumper is used as feet for truck tool boxes and job boxes, as a headboard bumper to protect walls, and as screw-on feet for large equipment such as generators, welders, water tanks and equipment skids.
Frequently asked questions
What size are cargo trailer ramp door bumpers?
The most common size is 3-3/16" diameter by 1-1/4" tall with a 3/8" mounting hole. Some trailers use other sizes, so measure your old bumper before ordering.
What hardware do I need?
A 3/8" bolt with a nut and washer, or a 3/8" lag screw into a wood frame. Hardware is not included because the length depends on your door and frame.
Why does my ramp door rattle when towing?
Worn, compressed or missing bumpers are a common cause, because the door can move against the frame. Replacing the bumpers, and checking that the door latches pull it snug, usually stops it.
Will this bumper fit my trailer brand?
If your old bumper measures 3-3/16" across, 1-1/4" tall, with a 3/8" bolt hole, this bumper is the same size. We list dimensions rather than trailer brands, so check your measurements.
Do you sell ramp door bumpers in bulk?
Yes. Single bumpers, 4-packs and bulk cases are available. See bulk case pricing, or request a quote for pallet quantities.
