RGN Trailer Dimensions: Standard, Stretch & Multi-Axle Specs
Knowing exact RGN trailer dimensions is critical for quoting accurate rates, determining permit requirements, and confirming that equipment fits safely. This guide covers every dimension — well length, deck height, overall length, width, and back deck specs — for standard, stretch, and multi-axle RGN configurations.
48 ft
Standard Overall Length
26-30 ft
Standard Well Length
18-24"
Well Deck Height
74 ft
Max Stretch Length
O Trucking Editorial Team
Trucking Industry Experts
Fact-Checked by O Trucking Dispatch Team
5+ years verifying RGN trailer dimensions for load planning, permit applications, and route clearance analysis
This article was written by the O Trucking editorial team with 9+ years of combined trucking industry experience. Learn more about us.
O TruckingRGN Trailer Dimensions: Standard, Stretch & Multi-Axle Specs (2026)
Standard RGN Trailer Dimensions
A standard (non-stretch) RGN trailer with 2-3 axles is the most common configuration used in heavy haul trucking. Here are the typical specifications:
| Dimension | Measurement | Notes |
|---|---|---|
| Overall Length | 48 ft (576 in) | Gooseneck + well + back deck combined |
| Well Length | 26-30 ft (312-360 in) | Lowest section where equipment sits |
| Well Deck Height | 18-24 in | Depends on tire size and suspension type |
| Width | 8 ft 6 in (102 in) | Maximum legal width without oversize permit |
| Back Deck Length | 10-13 ft (120-156 in) | Elevated section behind rear axles |
| Back Deck Height | 36-48 in | Higher than well; above rear axles |
| Gooseneck Length | 8-10 ft | Connects trailer to tractor fifth wheel |
| Trailer Tare Weight | 16,000-20,000 lbs | Empty trailer weight (2-axle configuration) |
These are typical specs for manufacturers like Fontaine Trailer, Trail King, Talbert, XL Specialized, and Landoll. Exact measurements vary by manufacturer, model year, and optional features. Always verify the specific trailer's dimensions before booking — especially the well length and deck height, which directly determine whether the equipment fits.
Anatomy of an RGN Trailer
An RGN trailer has three main sections, each with different heights and functions:
Gooseneck (Front Section)
The gooseneck is the elevated front section that connects to the tractor's fifth wheel via a kingpin. On an RGN, this section is detachable — it disconnects hydraulically for loading. It is 8-10 feet long and sits at approximately the same height as the tractor's fifth wheel (typically 48-52 inches). The gooseneck transitions downward to meet the well section.
Well (Main Deck / Lowest Section)
The well is the primary cargo area — the lowest point on the trailer at 18-24 inches above ground level. This is where the heaviest part of the equipment sits. The low height maximizes vertical clearance for tall equipment while keeping the center of gravity as low as possible for stability. Standard well length is 26-30 feet; stretch configurations extend to 61 feet.
Back Deck (Beaver Tail / Tail Section)
The back deck sits behind and above the rear axle group, at approximately 36-48 inches. This section is 10-13 feet long and is used for lighter auxiliary items — toolboxes, attachments, or the counterweight/boom section of equipment that extends past the well. Some RGN trailers have flip-up ramps at the rear for secondary drive-on loading capability.
Stretch RGN Trailer Dimensions
Stretch RGN trailers have an extendable midsection that telescopes to increase the well length. This is essential for hauling long equipment that exceeds the standard 26-30 foot well. Here are the key stretch specifications:
| Dimension | Retracted | Fully Extended |
|---|---|---|
| Overall Length | 48 ft | Up to 74 ft |
| Well Length | 29 ft | Up to 61 ft |
| Extension Range | Typically adds 20-32 ft to the well | |
| Back Deck | 13 ft (does not change with extension) | |
| Deck Height | 18-24 in (same as standard) | |
The stretch mechanism uses a telescoping steel section in the middle of the well. When extended, the trailer's structural capacity per linear foot decreases slightly because the same frame is spread over a longer distance. This means stretch RGNs typically carry the same total weight as standard RGNs but distribute it over a longer span.
For a detailed guide on stretch configurations, when they are needed, and their permit implications, see our stretch RGN trailer guide.
Stretch RGNs Almost Always Require Over-Length Permits
Multi-Axle RGN Configurations
For loads exceeding the capacity of a standard 2-3 axle RGN, multi-axle configurations distribute weight across more contact points. Each additional axle increases legal weight capacity by approximately 10,000-12,000 lbs, depending on axle spacing and state regulations.
| Configuration | Approx. Payload | Typical Overall Length | Common Uses |
|---|---|---|---|
| 2-axle RGN | 42,000-44,000 lbs | 48 ft | Standard construction equipment |
| 3-axle RGN | 52,000-54,000 lbs | 48-53 ft | Larger excavators, motor graders |
| 5-axle RGN | 80,000-90,000 lbs | 53-60 ft | Large cranes, mining equipment |
| 7-9 axle RGN | 100,000-120,000 lbs | 58-65 ft | Transformers, heavy industrial |
| 13-20 axle RGN | 120,000-150,000+ lbs | 60-80+ ft | Superloads: reactors, generators, military |
Multi-axle RGNs often use steerable rear axles that pivot during turns, preventing tire scrub and allowing the trailer to track properly on curves. Some ultra-heavy configurations use a dual-lane trailer (two side-by-side decks) that is wider than a standard 8'6" trailer — requiring overwidth permits on every route. For weight capacity details, see our RGN trailer weight capacity guide.
Height Clearance Calculations
One of the RGN trailer's biggest advantages is the low deck height, which maximizes vertical clearance for tall equipment. Here is how to calculate whether your load fits under the legal height limit:
Height Clearance Formula
Total Height = Equipment Height + Well Deck Height
Legal Limit: 13'6" (162 inches) in most states
Available Clearance = 162 inches - Deck Height
18" deck: 162 - 18 = 144 inches (12 ft) of equipment clearance
22" deck: 162 - 22 = 140 inches (11 ft 8 in) of equipment clearance
24" deck: 162 - 24 = 138 inches (11 ft 6 in) of equipment clearance
For comparison, a standard flatbed has a deck height of approximately 60 inches, leaving only 102 inches (8 ft 6 in) of clearance. A step deck sits at about 36-42 inches, providing 120-126 inches (10-10.5 ft). The RGN's 18-24 inch deck provides 36-42 more inches of clearance than a step deck — often the difference between fitting under the legal limit and needing an over-height permit.
Always Add 2-3 Inches for Chain Binder Height
When RGN Dimensions Trigger Permits
Understanding which dimensions require permits helps you quote accurately and avoid legal issues on the road:
Over-length — Most states: 53-65 ft total vehicle length (tractor + trailer). A standard 48-ft RGN plus a 20-ft tractor = 68 ft, which exceeds the limit in some states. Stretch RGNs at 74 ft always exceed it.
Over-width — Legal limit is 8'6" (102 in). The trailer itself is within limits, but equipment that overhangs the deck sides (excavator buckets, dozer blades) often exceeds 8'6".
Over-height — Legal limit is 13'6" in most states (13'0" in some). Equipment height plus deck height must stay under the limit or you need a permit.
Overhang — Some states have separate overhang limits (how far the load extends beyond the front or rear of the trailer). Front overhang is typically limited to 3-4 ft; rear overhang to 4-6 ft.
For a comprehensive guide to permits by state, including escort vehicle requirements and application procedures, see our RGN trailer permits and regulations guide.
How Our Team Verifies Dimensions
At O Trucking LLC, accurate dimensions drive every heavy haul booking:
Equipment measurement verification
We collect exact equipment dimensions from the shipper — height, width, length, and weight — and verify them against manufacturer specs before matching a trailer. This prevents the costly mistake of sending the wrong size trailer to a job site.
Trailer spec matching
We confirm the specific trailer's well length, deck height, and weight rating with the carrier before booking. Not all RGN trailers have the same specs — a 22-inch deck versus an 18-inch deck can be the difference between fitting under the legal height and needing a permit.
Clearance calculation and permit flagging
We calculate total loaded height, width, and length before every booking and flag any dimension that triggers a permit. Permits are applied for in advance so there are no delays when the driver arrives at the job site.
Need a Dispatch Team That Gets the Dimensions Right?
Our dispatchers verify equipment dimensions, match trailer specs, and calculate clearances before every heavy haul booking. No guesswork, no surprises at the job site.