A 4 inch hose clamp has a harder job than most people expect. At this size the band wraps more than a foot of hose, the hose itself is usually something unusual (wire-helix duct, a silicone intake elbow, a corrugated suction line), and the people buying it are coming from very different places: a woodworker hooking up a dust collector, a fleet mechanic replacing an air intake boot, a facilities tech hanging exhaust extraction hose in a service bay, or a contractor priming a trash pump. Each of those jobs points to a different 4 inch hose clamp.
Below, we cover what changes physically once a clamp gets this big (the reason a clamp that works on a radiator hose can fail on a 4″ duct), then map the four most common 4-inch jobs to a clamp type and OneTouch Exim part number.
One rule applies all the way through: “4 inch” usually describes the hose’s inside diameter or the port it slides onto, not the surface the clamp sits on. The clamp closes around the outside diameter of the hose as installed on the fitting. On a 4″ port, that number might be 4.10″, 4.30″ or 4.60″ depending on the wall. Measure it, then pick a clamp whose range puts that measurement somewhere near the middle.
What changes when the circumference passes 12 inches
The circumference of a 4″ circle is π × 4, or about 12.57 inches. A 1″ heater hose clamp wraps about 3.14 inches of hose. So a 4″ clamp has four times as much band in contact, four times as much band to stretch, and one screw housing doing all the work. Three things follow from that.
1. You need more band tension for the same sealing pressure
A clamp band works like a hoop. The radial pressure it puts on the hose is roughly the band tension divided by the radius times the band width. Keep the tension and width the same, double the radius, and the pressure on the hose is cut in half. In practical terms, a 4″ clamp with a 1/2″ band has to pull about twice as hard as a 2″ clamp to squeeze the hose wall with the same force per square inch.
That is why a standard worm gear clamp can feel tight at 4 inches and still leak: the screw reaches familiar torque, but pressure at the hose surface is lower. It is also why hi-torque clamps exist mainly in the larger sizes.
2. A longer band stretches more
Steel stretches in proportion to its length under a given stress. A 12-plus-inch band under high tension elongates more in total than a 3-inch band does, and the screw has to take up that stretch before it starts compressing the hose. You feel this as a “spongy” clamp that keeps turning without biting. Later, when the hose takes a set, the long band relaxes with it.
The geometry works against you too. Each 0.10″ of band you take up reduces the diameter by only about 0.03″ (0.10 ÷ π). So the screw has to travel a fair amount to squeeze a 4″ hose down by even a small amount, and a small amount of hose shrinkage gives back a surprising length of band slack.
3. The housing wants to roll, and the pressure is not even
On a worm clamp, all the tension is generated at one point: the screw housing. As you tighten, the housing is pulled in two directions along a curved surface, and on a big-diameter hose with a soft wall it can tip or rock instead of seating flat. A tilted housing loads one edge of the band and leaves the other edge loose. Friction between the band and hose also means tension is highest near the housing and tapers off as you move around the wrap, so the side opposite the screw tends to get the least squeeze.
Add a wire-reinforced hose and the picture gets more uneven. The band rides on the high points of the helix wire and bridges the low spots between coils. Pressure piles up where the band crosses the wire and drops where it spans the gap. On low-pressure air that’s usually fine. On anything under real pressure or vacuum, it’s where leaks start.
The clamp types that handle these problems best are the ones that spread load more evenly: T-bolt clamps with a solid band and a bolt that pulls from a full-width bridge, hi-torque clamps with a stiffer housing, and constant torque clamps that store spring force in Belleville washers to keep the band loaded as the hose relaxes. Which one you need depends on the job.
Pick your 4-inch use case
Most people searching for a 4 inch hose clamp are doing one of four jobs. Each has a different main threat: vibration, heat, vacuum, or a floppy hose that needs to stay put.
Dust collection: the 4 inch dust collection hose clamp
Shop dust collectors, table saws, planers and jointers very often use 4″ ports with 4″ flexible hose. This is the lightest-duty job on the list. The system runs at a small negative pressure, there’s no heat, and the hose isn’t carrying liquid. The clamp’s real jobs are to keep the hose from pulling off when someone drags it across the floor and to stop air from leaking in around the port, which robs suction at the tool.
A standard worm gear clamp is the right tool here. Most 4″ flex hose slid onto a 4″ port lands somewhere around 4.1″ to 4.4″ OD, which sits near the middle of the OTE-4SC0064 worm clamp (3.56″ to 4.50″). If your hose is unusually thick or the port is oversized, step up to OTE-4SC0072 (4.06″ to 5.00″).
Wire-helix hose needs a little technique. Most dust collection hose has a spiral steel wire molded into a thin PVC or polyurethane wall. Push the hose fully onto the port first, then place the clamp so the band sits over the wire and the wall together, not in a stretch of hose that has no wire under it at the cuff. Tighten until the band is snug over the wire and the thin wall between the coils is pressed against the port. Then stop. Cranking harder only crushes the wire into an oval, which opens a gap on the other side.
Truck and equipment air intake ducts
On heavy trucks, buses, tractors and generator sets, the duct between the air cleaner and the turbo inlet is commonly in the 3.5″ to 5″ range, and 4″ is a frequent size. These joints use rubber or silicone elbows and hump hoses. The duct runs under mild vacuum, so the clamp isn’t fighting high pressure. What it is fighting is constant vibration, engine rock on its mounts, and heat soak from the engine bay.
This joint sits on the clean side of the air filter. A loose clamp here lets unfiltered, dusty air straight into the turbocharger and engine.
For this job, step up from the standard worm clamp:
- Hi-torque worm clamps are the common OEM-style answer for intake ducts. The OTE-4SCH412 hi-torque clamp (3.25″ to 4.13″) fits a 4″ hose with a thin wall, and OTE-4SCH462 (3.75″ to 4.63″) is the better fit when the installed OD comes out above about 4.1″. The heavier housing resists the rolling problem described above.
- T-bolt clamps give the most even 360-degree grip and are the usual choice for silicone intake hose. The OTE-4TB0400 T-bolt clamp (4.00″ to 4.31″) and OTE-4TB0425 (4.25″ to 4.56″) cover most 4″ ducts. T-bolt ranges are narrow, so measure before you order.
- Spring-loaded T-bolt clamps belong on the pressure side, after the turbo, where a 4″ charge-air hose to the intercooler sees boost pressure and big heat cycles. The OTE-4ST406H heavy-duty spring T-bolt (4.06″ to 4.38″) uses a spring to keep load on the silicone as it cold-flows and shrinks.
If you are replacing a clamp by an OEM part number from Cummins, Volvo, Freightliner, Mack or Caterpillar, the clamp cross-reference tool lists interchange numbers so you can match the original. Names and numbers are listed for reference only; OneTouch Exim is not affiliated with those manufacturers.
Exhaust extraction and ventilation hose: the 4 inch exhaust hose clamp
Service bays, fire stations and test cells run flexible extraction hose from a ceiling reel or fan down to a tailpipe adapter, and 4″ is a very common diameter. The hose is usually a high-temperature fabric or steel-ply construction, and the clamp holds it to the adapter nozzle or the overhead duct.
Two things drive the choice. First, heat: the nozzle end can get hot enough to soften plastics and bake off any plating. Second, condensation: exhaust gas carries water and acidic compounds that condense in the hose as it cools. A zinc-plated carbon steel screw will rust in that environment, and a rusted screw is the part that seizes or snaps the next time you need to swap a nozzle.
So the right 4 inch exhaust hose clamp is an all-stainless one. The OTE-4SS0064 all-stainless worm clamp (3.56″ to 4.50″) has a stainless screw as well as a stainless band, and covers the typical 4″ extraction hose cuff. For the hottest joints at the nozzle, a T-bolt with a solid band holds better as the hose material softens. If you’re curious why some stainless grades handle corrosive condensate better than others, our guide to 304 versus 316 stainless steel covers the differences.
A clarification that saves a lot of wrong orders: a hose clamp is for a hose. If you are joining two 4″ exhaust pipes at a slip joint, you need an exhaust band clamp or a U-bolt muffler clamp, which OneTouch Exim does not list. If you are joining two flanges (turbo outlet, EGR, DPF sections), that is a V-band clamp job, not a hose clamp job.
Pump suction lines
Trash pumps, dewatering pumps and transfer pumps in the 4″ class use reinforced suction hose on a barbed or shank fitting. This is the toughest job on the list for one simple reason: the line is under vacuum. Instead of being pushed outward against the clamp, the hose wall is being pulled inward and the joint is trying to suck air.
A pinhole air leak at a suction joint is enough to make a pump lose prime. The joint looks dry because the leak flows in, not out, so crews often chase “bad pumps” that are really bad clamp joints.
Good practice for 4″ suction lines:
- Double clamp it. Two clamps side by side on the shank, with the screw housings turned 180 degrees from each other so the weak spot of one sits across from the strong spot of the other.
- Use suction-rated hose. A clamp can’t fix a hose wall that collapses under vacuum. The hose needs its own helix or reinforcement rated for suction.
- Prefer heavier clamps. Hi-torque clamps or T-bolts hold better on the thick, stiff wall of suction hose than a standard worm clamp. OTE-4SCH462 and OTE-4TB0425 are common picks when the OD lands around 4.3″ to 4.5″.
- Go all-stainless around water. Pumps live wet. A stainless screw will still turn after a season in a ditch.
Many 4″ pumps use camlock couplings at the pump body; the same rules apply at the hose shank behind the camlock.
4 inch hose clamp options from 3.8″ to 4.6″ OD
This table pulls together the OneTouch Exim clamps that cover the outside diameters you’ll typically find on a 4″ port or a 4″ ID hose. The “sweet spot” column shows where in each range a measured OD sits most comfortably, roughly the middle third, so the band has room to tighten and still adjust later.
| Part no. | Type | Range (in) | Range (mm, approx.) | Comfortable OD (in) | Best 4″ use |
|---|---|---|---|---|---|
| OTE-4SC0060 | Worm gear, SS band | 3.31–4.25 | 84–108 | 3.6–4.0 | Thin-wall duct on a slightly small port |
| OTE-4SC0064 | Worm gear, SS band (SAE 64) | 3.56–4.50 | 90–114 | 3.85–4.2 | Dust collection, general 4″ flex hose |
| OTE-4SC0072 | Worm gear, SS band | 4.06–5.00 | 103–127 | 4.35–4.7 | Thick-wall 4″ ID hose |
| OTE-4SS0064 | Worm gear, all stainless | 3.56–4.50 | 90–114 | 3.85–4.2 | Exhaust extraction, wet or outdoor jobs |
| OTE-4SS0072 | Wide-range worm, all stainless | 1.88–5.00 | 48–127 | Wide | Stock clamp for mixed sizes |
| OTE-4CT400L | Constant torque HD | 3.25–4.13 | 83–105 | 3.55–3.85 | Rubber hose with big heat cycles |
| OTE-4CT450L | Constant torque HD | 3.75–4.63 | 95–118 | 4.05–4.35 | Rubber hose with big heat cycles |
| OTE-4SCH412 | Hi-torque | 3.25–4.13 | 83–105 | 3.55–3.85 | Intake duct, thin wall |
| OTE-4SCH462 | Hi-torque | 3.75–4.63 | 95–118 | 4.05–4.35 | Intake duct, pump suction |
| OTE-4SCH914 | Wide-range hi-torque | 2.13–4.13 | 54–105 | Upper end only at 4″ | Shop stock, emergency repairs |
| OTE-4TB0375 | T-bolt | 3.75–4.06 | 95–103 | 3.85–4.0 | Silicone duct on undersize port |
| OTE-4TB0400 | T-bolt | 4.00–4.31 | 102–109 | 4.05–4.25 | Silicone intake hose |
| OTE-4TB0425 | T-bolt | 4.25–4.56 | 108–116 | 4.3–4.5 | Thick silicone, suction hose |
| OTE-4ST406H | Spring-loaded HD T-bolt | 4.06–4.38 | 103–111 | 4.1–4.3 | Charge-air (boost) hose |
Two notes on reading this table. The “SAE 64” on OTE-4SC0064 is a size code, not a diameter; it does not mean 6.4 inches. SAE size numbers under SAE J1508 are just labels for standard worm clamp ranges, and on OneTouch Exim part numbers the last digits match that code. So when someone asks for an SAE 64 hose clamp, this is the one.
Second, if you’re shopping in metric and searching for a 100mm hose clamp, note that 100 mm is 3.94″. A 100 mm hose ID will almost always mean an OD well above 100 mm, so OTE-4SC0064 or OTE-4SC0072 is likely, but the tape measure decides.
Close neighbors in the series: if your hose turns out to measure closer to three inches, see our 3 inch hose clamp size guide. If you are working with large exhaust stacks or bulk transfer hose, the 6 inch hose clamp guide picks up where this one ends.
Wide-range clamps: handy, but know the trade-off
OneTouch Exim lists two wide-range clamps that reach 4″: the OTE-4SS0072 all-stainless wide-range clamp (1.88″ to 5.00″) and the OTE-4SCH914 wide-range hi-torque clamp (2.13″ to 4.13″). One clamp covering a 2″ hose and a 4″ hose sounds ideal for a service truck or a maintenance crib, and in many cases it is.
Here is what you give up:
- Band overlap and tail. A band long enough to wrap 5″ leaves a lot of extra band when it’s closed down to a smaller size. That tail sticks out and needs trimming in tight spaces. At 4″ on OTE-4SS0072 the excess is modest.
- Edge-of-range use. On OTE-4SCH914, a 4.0″ OD is near the top of the range. If the hose is slightly bigger than you thought, you have almost no adjustment left, and above 4.13″ it won’t fit.
- More band, more stretch. The physics from the start of this article applies more strongly. A wide-range band is longer, so it stretches more and loses more preload when the hose relaxes.
- Slower install. Going from the open position to snug means running the screw a long way. A cordless driver with a 5/16″ nut setter helps, but finish by hand.
The fair verdict: wide-range clamps are excellent stock items and roadside fixes. For a permanent install on an engine or a pump you’ll depend on, a clamp sized to the hose is the better choice.
Install sequence for big-diameter hoses
Most problems with a hose clamp for 4 inch hose come from the install, not the part. Even the best 4 inch hose clamp can’t seal a joint that was never seated. Work through this order:
- Clean the fitting. Remove old hose residue, rust scale and dust from the port or pipe end. A wire brush or scotch pad on metal; a dry rag on plastic ports. Any ridge of old rubber is a leak path.
- Check the bead. Most 4″ intake pipes and pump shanks have a raised bead or barbs. The clamp must land behind the bead (on the hose side), never on top of it.
- Seat the hose fully. Push the hose on until it reaches the stop or covers the full shank. On stiff 4″ hose, a light film of water or soapy water helps it slide. Don’t use oil or grease on rubber intake hose; it can keep the hose slippery and let it walk off.
- Measure the installed OD. With calipers or a flexible tape, measure where the clamp will sit. If you use a tape around the hose, divide the circumference by 3.1416 to get the diameter.
- Pre-open and position the clamp. Slide the clamp on before the hose goes onto the fitting when you can; opening a band fully and re-threading it is slower at this size. Place it about 1/4″ from the hose end, behind the bead.
- Orient the screw for access. Turn the housing to where you can reach it with a socket later. On a vibrating engine, keep it away from anything it could rub on.
- Snug in stages. Tighten until the band contacts all the way around, then tap or press around the circumference to help the band settle and the housing sit flat. Then bring it up to final tightness.
- Tighten to spec, not to feel. Use the torque value from the clamp or equipment maker. Standard OTE worm clamps carry a 45 in-lb torque rating (check the product page for your size) and should not be pushed past it. T-bolts and hi-torque clamps take more, so follow their maker’s figure.
- Double up where it makes sense. On suction lines and long shanks, add a second clamp with the screw turned 180 degrees from the first.
- Run it, then re-check. Run the system, let it heat up and cool down, then check tightness again (see the next section).
How often to re-check a 4″ clamp
Under clamp load, rubber and silicone slowly flow out from under the band, a process called creep or cold flow, and the effect is strongest in the first few heat cycles. At 4″, the long band means even a small amount of hose shrinkage drops tension noticeably. A sensible starting schedule for a 4 inch hose clamp:
- Any new install on rubber or silicone: re-check after the first full heat cycle or first day of use. This is when most of the settling happens.
- Truck and equipment intake and charge-air ducts: check at every scheduled preventive maintenance service. Look for chafe marks, oil film at the joint (a sign of blow-by), and dust tracks on the clean side of the air cleaner.
- Pump suction lines: check every time the pump is set up at a new site, and any time it struggles to prime.
- Exhaust extraction hose: check nozzle clamps when you inspect the hose for burns or cracks. Replace any clamp with a seized or rust-stained screw.
- Dust collection: once or twice a year, or whenever you move a machine. If suction at a tool drops, check the hose connections before you blame the collector.
If you find yourself re-tightening the same joint repeatedly, that’s a signal to change clamp type rather than keep turning the screw. On rubber hose with large temperature swings, the OTE-4CT400L constant torque clamp (3.25″ to 4.13″) or its larger sibling OTE-4CT450L will keep load on the hose between inspections. On silicone boost hose, switch to a spring-loaded T-bolt. Replace any clamp with a kinked band or stretched perforations.
For the full lineup of solid-band options, the T-bolt clamp range covers sizes well above and below 4″, including spring-loaded versions.
4 inch hose clamp FAQs
What size clamp do I need for a 4 inch hose?
Size the clamp to the outside diameter of the hose after it’s pushed onto the fitting, not the 4″ label. A thin 4″ flex hose often measures 4.1″ to 4.3″ OD, which suits a 3.56″ to 4.50″ worm clamp like OTE-4SC0064. Thicker hose may need OTE-4SC0072 (4.06″ to 5.00″). Measure with calipers or a tape and pick a range with your number near the middle.
Is a 4″ hose clamp the same as an SAE 64 hose clamp?
Often, yes. SAE 64 is the standard worm gear size code for a clamp of roughly 3.56″ to 4.50″, which covers many 4″ hoses. The number 64 is a size label, not a measurement in inches or millimeters. OneTouch Exim’s OTE-4SC0064 is an SAE 64 clamp, and OTE-4SS0064 is the all-stainless version of the same size.
Can I use a regular worm clamp on 4 inch dust collection hose?
Yes. Dust collection runs at low pressure with no heat, so a standard worm gear clamp is plenty. Seat the hose fully, place the band over the helix wire and wall, and tighten until it is snug and the wall between coils is pressed to the port. Over-tightening crushes the wire out of round and can actually open a leak on the far side.
When should I use a 4 inch T-bolt clamp instead of a worm clamp?
Choose a T-bolt when the joint carries pressure, sees heavy vibration, or uses soft silicone hose, such as truck intake and charge-air ducts. The solid band spreads load evenly around the full circumference without cutting into the hose. T-bolt ranges are narrow, around 0.31″, so measure the installed OD carefully before choosing between OTE-4TB0400 and OTE-4TB0425.
Why does my 4″ suction hose lose prime even though the clamps look tight?
A suction line leaks inward, so you won’t see water at the joint. Air drawn in through a tiny gap is enough to stop a pump priming. Check that the hose is fully seated and the clamp sits behind the barb, add a second clamp with its screw turned 180 degrees, and use a heavier hi-torque or T-bolt clamp on thick suction hose.
Do I need stainless steel clamps for a 4 inch exhaust hose?
For exhaust extraction hose, an all-stainless clamp is the smart choice. Heat and acidic condensate from exhaust gas will rust a zinc-plated screw, which then seizes or snaps when you need to remove it. OTE-4SS0064 has a stainless band and screw. For joining exhaust pipes or flanges, you need an exhaust band clamp or V-band clamp instead of a hose clamp.
Get the right 4-inch clamp, in the quantity you need
Tell us the job, the measured hose OD, and how many you need, whether that’s a handful of clamps for one dust collector or export cartons for a fleet. OneTouch Exim quotes every order individually and ships worldwide. Send your list, including any OEM part numbers you’re replacing, through the clamp quote request form, or message us on WhatsApp at +91-7838759114 and we’ll confirm the size before anything ships.