Trailer Restraint, Dock Lock & Interlock Repair in Tacoma, WA
For trailer restraint and dock lock repair in Tacoma, WA, call (385) 325-7138 about a restraint that won't engage, won't release, or a trailer that can't leave the bay. This covers vehicle restraints, dock locks, communication lights and dock interlocks at commercial and industrial facilities across Pierce County.
If a trailer is trapped right now, say that first.
Call to describe the problem—if the dock is down or a trailer is held, say so first.
Independent service-request website. Calls may be shared with an independent commercial dock-and-door repair company. That provider confirms availability, scope, pricing, and service terms.
Facts checked: September 18, 2026.
What is a trailer restraint, and what have we got?
A vehicle restraint — also called a trailer restraint, truck restraint or dock lock — is the device that holds a trailer against the dock while people and lift trucks are working inside it. It stops the trailer creeping forward or pulling away early. It's a separate machine from the door and from the leveler, and when it fails the bay usually stops even though both of those still work.
There are three broad kinds:
- Hook-style restraints reach out and engage the horizontal bar under the back of the trailer. Different models use different engagement mechanisms.
- Wheel-based restraints grip or block a trailer wheel instead.
- Wheel chocks are another trailer-securing method, not a hook or wheel-engaging restraint mechanism. Some systems add sensing or communication equipment.
You don't need to know which you have. Say "the thing that grabs the trailer" and describe what stopped working.
Rite-Hite’s Dok-Lok and Global Wheel-Lok are examples of different restraint designs. Report a known brand or model; these names do not imply an Uptime affiliation or service authorisation.
What the lights and the equipment are telling you
Do not try to release a stuck restraint, override an interlock, or work around a fault to keep loading. No page should walk you through that, and this one won't. Keep people and lift trucks out of the trailer, take the position out of use through your facility's existing process, and describe what you're seeing.
| What the equipment shows | What needs attention at the bay | What to report | What stops until it's fixed |
|---|---|---|---|
| Won't engage at all | The trailer isn't secured by the restraint | Whether a trailer is at the bay now | Loading at that position |
| Engaged, but the inside light stays red | The system doesn't agree the trailer is held | What both lights show | Usually loading, by your own procedure |
| Won't release, trailer held | Driver can't leave | Say this first. Mention how long | The trailer, and often the next appointment |
| Released, but the outside light stays red | Driver has no clearance signal | What each light shows | The departure |
| Lights dark both sides | No communication between dock and driver | Whether anything else on that circuit is dead | The whole signalling side |
| Restraint damaged by a trailer | Something struck it | What hit it and when | That position |
| Interlock holding the door or the leveler | An expected hold or a fault needs assessment | Which equipment is held | The affected equipment |
| Control station unresponsive | Could be controls, could be power | Whether other stations work | The position |
An interlock links the restraint, door or leveler so operation depends on signals from the other equipment. A held door can be an expected part of that sequence or a fault. Report which equipment is held; do not bypass the interlock.
Lights, controls and interlocks
The red-and-green light package is the conversation between the driver outside and the crew inside. Outside red usually means "don't pull away." Inside green usually means "the trailer is secured." Usually is doing real work in both of those sentences — the exact meaning is set by the system and by your facility's procedure, so we're not going to tell you what your lights mean.
What matters for the call: report the inside and outside signals separately. They are not meant to show the same colour at all times—inside green and outside red can be a normal loading state. Report any known change from the system’s instructions, rather than calling different colours a mismatch.
Control stations, sensors and the wiring between them all sit in this system. New wiring reaches a separately licensed electrical trade in Washington under chapter RCW 19.28 — and the permit for it may come from a different office than your building permit. See the local rules below.
Do we still need wheel chocks?
Washington’s forklift rule allows a mechanical securing method instead of chocks only when it meets the rule’s conditions. WAC 296-863-40050 requires the method to prevent the trailer moving away, to be used and maintained according to the manufacturer, and to be taken out of service when damaged or malfunctioning.
WAC 296-24-75006 separately requires positive measures against vehicle movement while employees are on a dockboard. Those requirements do not make an unidentified or faulty restraint an automatic substitute for chocks.
Have the facility’s responsible safety person and qualified provider confirm the method for the actual equipment and operation. Keep a damaged or malfunctioning restraint out of service; do not improvise a bypass to keep loading.
National background on loading-dock equipment and how the pieces work together: loading dock repair.
What this covers, and what it doesn't
Covered: vehicle and trailer restraints, dock locks, restraint control stations and sensors, communication light packages, and dock interlocks between the restraint, door and leveler at commercial and industrial facilities.
Not covered:
- Any bypass, override, or manual-release procedure. This page does not provide these procedures
- Levelers — dock leveler repair
- Seals, shelters, bumpers, dock lights — dock equipment repair
- The door — overhead or roll-up
- Trailer repair. If the problem is the trailer's rear impact guard, that's a trailer shop
- Residential, boat docks, parts-only orders, structural concrete
What happens when you call
- You describe it. Facility address, bay number, what the restraint is doing, and whether a trailer is held.
- Your request can be shared. Calls may be shared with an independent commercial dock-and-door repair company.
- That company takes it from there. It confirms the address, scope, availability, price, and its own contract, work and warranty terms with you directly.
Example wording — not a real job, not a testimonial:
"The restraint on bay 9 at our Fife facility won't release and there's a driver waiting — I can give you the address."
Useful if you already have it: restraint type or brand, if it's on a plate you can read from where you stand · what both lights show · whether the door or leveler is also held by the interlock · how many positions have the same problem · access requirements. You can call without any of it. Nobody should go under or behind a trailer to look at a restraint.
If you reach voicemail, leave the facility address, the door or dock number if known, what's wrong, and a callback number.
What affects trailer restraint repair cost?
We can't quote your exact restraint repair from a web page. The price depends on the restraint type, the fault, parts, and whether the controls are involved. Here's what to ask before you authorize work.
Ask whether the first visit is diagnostic or repair, whether the control and light package are in scope or priced separately, and whether you're getting a call-out fee, a starting price, a scoped fixed price, an estimate or a final quote.
| Cost driver | Why it moves the price |
|---|---|
| Restraint type | Hook-style and wheel-based units are different machines |
| Mechanical vs. control fault | A seized hook and a failed board aren't the same job |
| Light package and interlock | Adds a second system to test and sometimes a second trade |
| Impact damage | A struck restraint may have moved its mounting too |
| Electrical scope | New wiring reaches a separately licensed trade and possibly a permit |
| Parts availability | Model compatibility and whether parts must be ordered |
| Access | Working at the dock face with live traffic |
| Number of positions | A run of ageing restraints prices differently from one |
Repair or replace?
A provider needs to assess the mechanism, controls and mounting before deciding on repair or replacement. Major impact damage or unavailable compatible parts can favour replacement. Trouble with only some trailers can involve compatibility, adjustment or a fault; the pattern alone does not diagnose it.
What to ask for: the finding, whether the mounting and dock face are still sound, whether the existing light and interlock package will work with a new unit, and both options priced separately.
Local checks before you authorize work
Checked September 18, 2026. These are the rules and the offices. Whether one applies to your job is for the provider and the issuing office to confirm.
- Registration. Construction contractors generally register with L&I under RCW 18.27. Look them up. WAC 296-200A-016 includes industrial equipment and machines at (29); ask which classification covers the restraint, anchorage and associated work. Electrical licensing is a separate question.
- Electrical. Restraint controls, sensors and light packages mean wiring, and wiring reaches a separately licensed trade under chapter RCW 19.28. In this county the electrical permit may come from Tacoma Power, which L&I says issues permits and performs inspections for properties it serves in "the cities of Tacoma, Fircrest, University Place, Fife, parts of Steilacoom, Lakewood, and unincorporated Pierce County as far south as Roy" (L&I). Tacoma Power electrical permitting: 253-502-8277. L&I's advice is blunt: verify jurisdiction before buying a permit.
- Safety rules. WAC 296-24-75006 and WAC 296-863-40050 address dockboards and trailer securing. DOSH covers most workplaces here; OSHA identifies the federal exceptions.
Where to call about this work
Call about facilities in Tacoma and across Pierce County. Fife, Sumner, Puyallup, Lakewood, Frederickson, DuPont, Bonney Lake, Parkland, Spanaway, South Hill and the rest of the county.
Questions before you call
The restraint won't release and a driver is waiting. What do we do?
Keep people out of the trailer, report it as a trapped trailer when you call, and follow whatever process your facility already has for an unsafe or stuck dock position. We're not going to publish a manual release procedure, because doing that wrong with a driver in the cab is exactly how people get hurt.
Is a dock lock the same as a trailer restraint?
In everyday use, yes — "dock lock" is what a lot of crews call the restraint. The word doesn't tell you which mechanism you have, so describe what it does rather than what it's called.
Can the interlock be turned off so we can keep loading?
Do not bypass an interlock to keep loading. A hold can be an expected system state or a fault; have the qualified provider assess it under the facility’s safety process.
What do the red and green lights actually mean?
They communicate system status between the driver and the dock crew. Their exact meaning follows the equipment instructions and facility procedure; inside green and outside red can be a normal combination. Report each signal separately, not whether the colours match.
Call about the restraint
Tell us the bay, what the restraint is doing, and whether a trailer is held.
Independent service-request website. Calls may be shared with an independent commercial dock-and-door repair company. That provider confirms availability, scope, pricing, and service terms.
Uptime Dock & Door is an independent commercial service-request website for loading-dock and commercial door repair. Keep Every Bay Moving.
Tacoma dock and door repair · Tacoma services · Tacoma phone page · About Uptime · Change service area
Sources
All checked September 18, 2026.
- WAC 296-24-75006 — Dockboards (bridge plates)
- L&I F414-126-000 — Safety Standards for Forklifts and other Powered Industrial Trucks (chapter 296-863 WAC)
- WAC 296-200A-016 — specialty contractor classifications
- L&I — Verify a Contractor, Tradesperson, or Business
- L&I — City Electrical Permits & Inspections
- Washington — securing trailers for forklift loading
- OSHA — Washington State Plan jurisdiction
- Rite-Hite — vehicle restraint mechanisms and communication
- Rite-Hite — Global Wheel-Lok