How we made this guide: picks and specs come from our catalog and fitment data, owner quotes come from verified reviews and the guide was drafted with AI help, then checked and edited by Trevor Hall.
A crossover truck tool box sits across the top bed rails behind the cab and is held down by four mounting clamps with carriage bolts, as Weather Guard's installation manual describes. Whether you drill depends on the box. Our listings say the Weather Guard 127, 117 and 174 need no drilling, the 548 underbody box bolts through to the frame and the UnderCover SwingCase needs some drilling on select trucks.
Plan on about 20 to 30 minutes for a crossover or lo-side box, with a socket or wrench set, a tape measure and a second person for the lift. Our 127 and 614 listings rate the install easy, best done with two people for the lift; the 548 listing rates it moderate. The 127 crossover, whose listing carries the install sheet followed below, is from $1,340.
| Box | How it mounts | Drilling | Time |
|---|---|---|---|
| Weather Guard 127 and 117 crossover | Saddles the top bed rails behind the cab | None; under-rail clamps and hardware included | About 20 to 30 minutes |
| Weather Guard 174 Lo-Side | Sits on top of one bed side rail | None; under-rail clamps and hardware included | About 20 to 30 minutes |
| Weather Guard 614 chest | Sits below the bed rail against the front of the bed | Tie-down straps or bolt-down hardware, per its listing | About 20 to 40 minutes |
| Weather Guard 548 underbody | Bolts to the frame rail below the deck | Yes; bolt-through, with brackets and hardware not included | About 1 to 2 hours |
| UnderCover SwingCase | Side-specific brackets at the wheel well | Some drilling on select trucks | 30 minutes or less on most kits |
Times and drilling come from each listing's Specifications; the crossover steps come from Weather Guard's sheet. Still choosing a box? Our guide to the best truck tool boxes compares the types, and you can browse all truck tool boxes we carry.
Before you start: measure and read the warnings
Measure first. Our listing says the 127 needs about 72 inches of rail-to-rail width and is not designed for compact or mid-size trucks, so check the room behind the cab. Our guide to truck tool box dimensions and how to measure your bed covers the numbers to take. If you run a tonneau cover, read which tool boxes fit under one first: the 614 chest sits below the bed rail, while crossover and lo-side boxes sit on top of it.
The sheet's opening notice adds two points. Check what your bed is made of first: on an aluminum bed, use the aluminum upfit components and follow the sheet's additional instructions for aluminum beds. And the box is for small tools and similar materials only: no gasoline containers, solvents, propane or acetylene tanks or cutting torches.
Tools and hardware the sheet lists
The sheet names two tools, a 1/2 inch ratchet wrench and a ruler. Our listing adds a tape measure and a second person to lift and hold the box while you clamp it, because it is wide; it weighs about 75 lb (80 lb shipping). The sheet's parts list:
- 4 mounting clamps
- 4 carriage bolts, 5/16-18 x 3 inches
- 4 fender washers and 4 retaining washers
- 4 nylon lock nuts, 5/16-18
- 1 tray and 2 keys
Weather Guard's own step-by-step guide to truck box hardware installation.
Installing a crossover box, step by step
These steps follow Weather Guard's installation manual for aluminum and steel saddle and cross boxes, the PDF on our 127 listing. Steps 1 and 2 are the sheet's own; steps 3 and 4 come from its lock and electrical pages. Park on level ground first, as the sheet says.
Full-size crossover
Weather Guard 127 Aluminum Crossover Truck Tool Box, Full-Size Standard, Bright Aluminum (127-0-04)
From $1,340 · The listing that carries this install sheet: a 72 inch saddle box with under-rail clamps and no drilling.
Step 1. Locate the box in the bed
Set the box on top of the bed rails. Use a ruler to confirm it is centered and that the lid opens fully without interference; the sheet's note says to check the room around the open cover. A liner may need to be drilled, trimmed or cut for the box to install properly, the sheet's notes add.
Step 2. Attach the box to the bed
Attach each mounting clamp with a carriage bolt and washers as the sheet's figure shows. Start with the slot at the driver's side front and work clockwise until all four clamps are in. Beds vary, so eight mounting slots are provided to ensure four clamps can be used.
Do not judge the lid yet: the sheet says the cover may not latch properly until the box is bolted down in four places. The sheet's figure shows where the clamps go, but it gives no torque figure (none is on file). Our listing says to tighten the hardware evenly so the box sits flat and the lid seals all the way around. The sheet says to check the clamps' tightness periodically.
“Amazing in every way! Install was a breeze with two people.”
Weather Guard 127 Aluminum Crossover Truck Tool Box, Full-Size Standard, Bright Aluminum (127-0-04) owner · 5 out of 5 stars
The 117 is a saddle box too, but it is the earlier generation with the One Key lock, and its listing links its own installation manual, so use that for its hardware and its lock.
Extra-wide crossover
From $1,189 · Clamp-in mounting per its listing, in a body 27-1/2 inches deep front to back, so measure before you order.
Step 3. Code and test the lock
These lock steps come from the 127 sheet. The 127 and 174 carry the 1Key UltraLock; the 117 has the earlier One Key lock, per its listing. Page 2 of the sheet says to read its lock instructions before a key goes into any lock. The locks ship with no preset code, and only the two keys provided can code them.
Remove the label, open the lid and insert a key. Turn it clockwise a full three quarters of a circle, then fully insert it again. The box is now locked with that key permanently coded. Remove the key and test: a quarter turn counter-clockwise unlocks and a quarter turn clockwise locks.
Once a lock is coded it cannot be changed, and the sheet says your key code cannot be found if you lose the keys, so register the box and key code with Weather Guard and keep your own record. Several boxes can share one key, or each can have its own set.
Weather Guard's own step-by-step guide to coding a 1Key UltraLock truck box lock, the lock on the 127 and 174. If it differs from your sheet, follow the sheet.
Step 4. Add power only through the grommet
Weather Guard boxes have a 12 volt access grommet for accessory wiring: cut along a perforation in the rubber and run the wire through. For an extension cord, the sheet says never to feed it through the hole without the grommet in place, to use an outdoor-rated three-wire cord on a 120 volt GFCI-protected outlet and to remove the cord before you move the truck.
Lo-side and chest boxes: what changes
A lo-side truck tool box is the crossover job on one side. The Weather Guard 174 is 56 inches long and sits on top of one bed side rail, and its listing says the included under-rail clamps and hardware mean no drilling. One of the 16 owner reviews on file still says the job took a drill and a wrench, so keep one handy. The listing gives about 20 to 30 minutes and advises a second person because of the length.
Measure the usable rail first: the listing says the 174 fits most 6'6" and 8' beds easily and many 5'6" short beds, so confirm the room behind the cab.
“I've had several of these boxes and they are dependable, Instruction on bolt installation is a little vague.”
Weather Guard 174 Lo-Side Truck Tool Box, 56" Bright Aluminum Diamond Plate (174-0-04) owner · 5 out of 5 stars
Lo-side box
Weather Guard 174 Lo-Side Truck Tool Box, 56" Bright Aluminum Diamond Plate (174-0-04)
From $981 · A 56 inch box for one bed side rail, with under-rail clamps and no drilling per its listing.
The 614 chest goes in differently. It sits in the bed against the front wall below the bed rail, and its offset cover design lets the cover open a full 90 degrees even with the chest pushed tight to the front.
The listing says to secure it with tie-down straps through the reinforced buckles or with bolt-down hardware, then confirm the cover opens fully and the weather seal closes all the way around. Allow about 20 to 40 minutes with a tape measure, a wrench or socket set and a helper.
Compact chest
Weather Guard 614 Aluminum All-Purpose Chest Truck Tool Box, Compact 7.0 cu ft, Clear (614-0-04)
From $885 · Sits below the bed rail at the front of the bed, so its listing says it clears tonneau covers.
Underbody boxes bolt to the frame, not the bed
An underbody box such as the Weather Guard 548 is not built for a pickup bed floor. It mounts to the frame rail below the deck of a flatbed, platform, service or dump body. It can also go under a pickup bed when the frame has room, but the listing's fit table says it does not mount on the bed floor.
The 548 listing puts a drill on the tool list: bolt-through mounting in about 1 to 2 hours with a drill and bits, a wrench or socket set, a tape measure and a marker. Brackets and hardware are not included, so buy hardware rated for the box plus its contents. Support the box while you fasten it and seal any drilled holes with zinc-rich primer.
The listing puts the steel box at about 100 lb and says it needs about 48 inches of clear rail and 18 inches of depth, plus room below for the drop door. It points to Weather Guard's underbed boxes installation manual for hole layout.
Underbody box
Weather Guard 548 Underbed Truck Tool Box, 48 in Black Steel, 9.1 cu ft (548-5-02)
From $930 · Frame-rail mount for flatbed and service bodies; brackets and hardware are not included.
The SwingCase installs at the wheel well
The UnderCover SwingCase is a 1.5 cubic foot case rated for up to 75 lb that bolts into the space between the rear wheel well and the tailgate. Each part is made for one truck generation and one side, with a side-specific truck bracket, a striker bracket and hardware for your truck.
The listing says some drilling is required on select trucks: some kits bolt to holes and inserts the bed already has, while others use self-drilling screws. It puts most kits at 30 minutes or less, and the tools change by kit: the 2005 to 2023 Tacoma passenger-side listing names only a T30 Torx, while the 2022 to 2026 Tundra driver-side listing (SC404D) calls for a drill with a 17/64 inch bit and a 10 mm wrench or socket. Six of the 141 owner reviews on file mention using a drill, for pilot holes, holes in a drop-in liner or driving the screws, and one owner found the holes already there.
“Easy installation if you drill starter holes for the screws. Fits perfectly. The quality is reasonable.”
UnderCover SwingCase Swing-Out Truck Bed Toolbox owner · 5 out of 5 stars
A plastic drop-in liner has to be trimmed because the brackets must sit on the bed's sheet metal, while a spray-in liner is no problem. The listing says the case works with most tonneau covers but not with bed extenders, and a few kits name covers they do not fit, printed on that truck's page.
Swing-out case
UnderCover SwingCase Swing-Out Truck Bed Toolbox
From $219.99 · Driver and passenger cases are separate parts, so pick your truck and side.
After the install: check the lid, the seal and the hardware
- Lid: it should open fully without touching the cab or the rails.
- Latch: it should latch on both sides once all four clamps are tight. If a striker has been knocked out of alignment, the sheet says to re-align it with a mallet.
- Seal: the weather strip should close evenly all the way around.
- Lock: test a quarter turn each way and keep a record of the key code.
- Hardware: check the clamps' tightness periodically and touch up any drill holes with paint to prevent oxidation, as the sheet says.
The sheet says the latch needs only minimal maintenance: lubricate its pivot points with white grease bi-annually. One 117 owner, with a 117-52-02 on a 2017 F-350, describes a box that would not latch on both sides:
“As other reviews have said you have to get into the bed and push this lid from the center to get this box to positively latch on both sides.”
Weather Guard 117 Aluminum Crossover Truck Tool Box, Full-Size Extra-Wide, Bright Aluminum (117-0-03) owner · 2 out of 5 stars
If yours does that, the sheet's two checks are the clamps, since the cover may not latch until the box is bolted down in four places, and the striker alignment, which it says to correct with a mallet.
Common mistakes
- Putting a key in the lock before reading page 2. The code is permanent.
- Skipping the centering and open-lid check.
- Feeding a cord through the grommet hole with the grommet removed, or storing gasoline, solvents or propane in the box.
- Modifying the box. The sheet says any modification or unintended use voids the warranties, and the warranty excludes defects from failing to mount the box as the written instructions say.
- Losing the receipt. The sheet's limited lifetime warranty covers the original purchaser only, and a claim needs a copy of the sales receipt.
Frequently asked questions
How do you install a tool box in a truck bed without drilling?
Choose a box that comes with under-rail clamps. Our listings say the included clamps and hardware mean no drilling is required on the Weather Guard 127, 117 and 174. The 614 chest can be held with tie-down straps through its reinforced buckles instead of bolt-down hardware, per its listing.
Do you need J-bolts to install a truck tool box?
Not with the clamp kit. Weather Guard's 127 sheet uses four mounting clamps with 5/16-18 x 3 inch carriage bolts, and it mentions through bolts or J-bolts only for a drilled bed. If you drill an aluminum bed for them, the sheet says to coat the holes with zinc-rich primer, which is not included, before assembly.
Does a tool box get bolted down to a truck?
Every box is fastened somehow: four clamps on the 127, tie-down straps or bolt-down hardware on the 614 chest, bolts through to the frame rail on the 548 and side-specific brackets on the SwingCase.
How do you keep a truck tool box from sliding?
Center it with a ruler, fit all four clamps and check their tightness periodically, as the 127's sheet says. For the chest, set it against the front wall of the bed and use straps or bolt-down hardware.
How long does it take to install a truck tool box?
Our listings say about 20 to 30 minutes for the 127, 117 and 174, about 20 to 40 minutes for the 614, 30 minutes or less for most SwingCase kits and about 1 to 2 hours for the 548. The crossover, lo-side and chest listings advise a second person.
Can I put a tool box under a tonneau cover?
Some boxes can. The 614 chest sits below the bed rail, and its listing says that clears tonneau covers, lids and truck caps. The SwingCase listing says it works with most tonneau covers but not with bed extenders. Crossover and lo-side boxes stand on the rails, so a standard cover will not close over them: a lo-side box suits a truck run without a standard cover, and a crossover box needs a cover made to work with a tool box.
Find a tool box that fits your bed