Walk through any truck show, any sled-pull pit, any diesel forum on the planet, and you'll see the same intake bolted to half the rigs there. There's a reason: an S&B cold air intake is the cheapest, easiest, highest-impact thing you can hand-tighten onto a diesel — and it's the rare bolt-on that actually delivers on every promise it makes. Better airflow, better filtration, better sound, and a hood you can pop with pride. No snake oil.

But cold air intakes have a credibility problem because the gas-truck world spent twenty years over-promising tiny gains. The diesel story is different — and worth telling straight. Here's exactly what an S&B intake actually does on a Cummins, Power Stroke, or Duramax, what to expect, and how to pick the right one. If you'd rather just have us spec it, send us your truck.

What a cold air intake actually does

A cold air intake replaces the stock airbox, filter, and intake tubing with a higher-flow filter (usually in a sealed housing that pulls air from the coolest spot it can find) and a smoother, larger-diameter tube to the turbo. On paper that does four things:

• Increases airflow to the turbo by reducing the restrictions that the OEM box and paper filter introduce on purpose to meet a cost target.
• Improves filtration with a higher-quality media designed to catch fine particulate without choking off airflow.
• Pulls cooler air by isolating the filter from engine-bay heat and feeding it from a fender or cowl pickup.
• Makes the truck sound better — the underrated benefit nobody admits matters until they hear their first big turbo spool through a real intake.

On a gas truck, that's worth a couple of horsepower if you're lucky. On a diesel? It's a completely different conversation.

Why diesel is different (and why the gains are bigger)

A diesel is an air pump in a way a gas engine isn't. Diesel power scales with air and fuel, and the EFI tune (or your aftermarket tune) is constantly adjusting fueling based on what your sensors say is happening in the intake. Two things matter:

• Cooler, denser air = more oxygen per cylinder. On a turbocharged diesel that's already cramming air in under boost, an extra few percent of intake-charge density meaningfully helps fueling do its job and cleans up combustion.
• Less restriction = better turbo response. Spool feels quicker, EGTs come down a hair under tow, and the truck just feels like it's breathing.

You won't dyno an extra 100 HP on intake alone — anyone telling you that is lying. But the gains you do get are real, you feel them, and they stack with every other upgrade you bolt on after.

The S&B lineup at a glance

S&B Filters has spent the last two decades obsessing over airflow and filtration for diesel pickups, off-road UTVs, and race rigs. That's why their stuff fits like a glove and their filters punch above their weight on flow-vs-filtration testing. Here's what we stock at DNR Customs:

S&B Cold Air Intakes

The headline product. Sealed housing, large-diameter tube, available with either a cotton (oiled) filter or S&B's signature dry PowerStack filter. Application-specific for every late-model diesel pickup, complete with mounting hardware and instructions a normal human can follow.

S&B Replacement Filters

Drop-in OEM-shape filters that fit the stock airbox. Not as much flow gain as a full intake, but a real filtration upgrade if you're not ready to swap the whole housing. Great for trucks under warranty.

S&B Fuel Tanks

This one surprises people. S&B also makes larger-capacity replacement fuel tanks — the kind of mod that pays off the first long highway run when your buddies are gassing up and you're not. Browse them in the S&B collection next to the intakes.

Cotton vs Dry: which S&B filter should you run?

This is the question we get on every S&B install. Both filter media are excellent; they have different strengths.

Quick translation: if you want absolute peak flow and you'll actually clean and re-oil it on schedule, run the cotton filter. If you want a great-flowing filter that just gets washed and re-installed with no oil step, go dry PowerStack. Both protect your engine; pick the maintenance routine you'll actually do.

Platform by platform: which S&B for your truck

S&B builds application-specific intakes — there is no "universal" intake here, and that's a good thing. The kit you order is built for your year, engine, and chassis.

RAM Cummins (5.9L & 6.7L)

The Cummins crowd has the deepest S&B catalog. From the 5.9 12-valves up through the latest 6.7 5th-gens, there's an intake that fits. If you're stacking other upgrades — a FASS lift pump, a Fleece Cheetah turbo, or you're working through our 6.7 Cummins first 5 upgrades guide — the S&B should be on the list. Round out the package from the Cummins collection.

Ford 6.7L Power Stroke

The Power Stroke airbox is one of the more restrictive OEM setups around, so the gains here are particularly noticeable. The 6.7 PSD also pairs the intake with serious benefits in turbo response and a much-improved engine-bay aesthetic. Pair it with your Power Stroke parts and consider CP4 protection while you're spending money.

GM Duramax (LB7 through L5P)

Duramax owners running an S&B almost universally come back and tell us the truck breathes better and sounds the way it always should have. Browse the matching Duramax parts to keep building.

Other engines

S&B doesn't only build for diesel — there are intakes for gas applications and replacements for the wider air intakes & filters category if your project sits outside the big three.

Real gains: what to actually expect

Let's be honest about what an intake does and doesn't deliver.

• Horsepower: on its own, a handful — call it 5–15 wheel HP depending on platform and tune. Modest, but it's real and stacks with every other mod.
• Fuel economy: usually a small, measurable bump — typically a fraction of an MPG that adds up over thousands of highway miles.
• Turbo response: noticeably quicker spool and stronger pull off boost. This is what owners actually feel.
• EGT: a hair lower under load, which means a little more margin while towing.
• Sound: the underrated payoff. You'll hear the turbo breathe, you'll hear the spool, and you'll never go back to a stock airbox.
• Filtration: arguably the biggest long-term win. Better filtration = a cleaner intake tract, cleaner turbo blades, and a longer-lived engine.

If somebody is selling you triple-digit horsepower from an intake alone, walk. Anyone selling you a quality S&B intake from the S&B lineup with realistic expectations is telling you the truth.

Does an S&B intake hurt my MAF? Will it void my warranty?

Two questions we get on every install — both with good news.

MAF compatibility: the urban legend that aftermarket intakes "kill" mass airflow sensors comes from old, sloppy oiled-filter installs where someone over-oiled a cotton filter and contaminated the MAF wire. With a properly serviced cotton filter — or simply running S&B's dry PowerStack — that's a non-issue. Either way, follow S&B's service instructions and your MAF is fine.

Warranty: federal law (the Magnuson-Moss Act) prevents a manufacturer from voiding your warranty just because you installed an aftermarket part. They can only deny a warranty claim if they can prove the aftermarket part caused the specific failure they're being asked to cover. A correctly installed, correctly serviced S&B intake is not breaking anything; it's actually filtering better than stock. Don't let the dealer scare you.

Install: a Saturday morning, tops

The full S&B cold air intake install is one of the friendliest jobs on a diesel:

• Pop the hood, unhook the stock airbox and intake tube (10–20 minutes of hand work, no special tools).
• Bolt the new sealed housing into the same mounting points (S&B uses OE mounts).
• Drop in the filter, clamp the new tube to the turbo inlet, route the breather lines per the instructions.
• Reconnect electrical (MAF, IAT) and double-check everything is tight.
• Fire it up, listen, smile.

If you can change your own oil, you can do this install. If you'd rather have it done while you're already in for other work, we'll take care of it.

Maintenance: the part most owners skip

Aftermarket filter media only outperforms OEM if it gets serviced. Here's the cheat sheet:

• Cotton (oiled): inspect every oil change; wash and re-oil when it looks dirty (typically every 30–50k miles depending on dust). Use S&B's recharge kit — over-oiling is the #1 mistake.
• Dry PowerStack: tap out the dust, wash with mild detergent and water, let it fully dry, drop it back in. No oil. Service when visibly dirty.
• Either filter: check it before and after every desert/dusty trip.

Service it on schedule and a good S&B filter will outlast multiple stock filter replacement cycles.

S&B vs the rest of the diesel intake market

We're not going to bash competitors — there are several quality intake brands. But here's why we keep recommending S&B more than anyone else for these trucks:

• Fitment is dialed. Their kits go in clean; you're not hunting for missing brackets or fighting with a tube that doesn't quite want to clamp.
• Filtration is best-in-class. When you look at independent filtration testing for the diesel space, S&B is consistently at or near the top.
• The dry PowerStack option is, in our opinion, the best maintenance-free filter on the diesel market.
• They actually carry replacement filters in stock for years and years. You'll find a service filter when you need one.

Want our head-to-head take, including the answer to the perennial "is a cold air intake worth it on a diesel" debate? It's right there in the companion guide.

High-dust environments: what to know

If you live and drive in dusty country — farm trucks, ranch trucks, oil-field trucks, anywhere off-road dust is part of daily life — your intake situation deserves extra thought. The good news: a sealed S&B housing with quality media is dramatically better at keeping dust out of your engine than an OEM box with a loose-fitting paper filter. The flip side: dusty environments demand more frequent service. Practical guidance for dust-heavy use:

• Service intervals shrink. Inspect at every oil change and service the filter when it looks loaded — not on a calendar.
• Pre-filters and outerwears (when available) extend the life of the main filter and keep your service interval reasonable.
• The dry PowerStack tends to be friendlier to high-dust service routines because there's no oil step — wash, dry, reinstall.
• Check the sealing edges when you service it. A clean seal around the filter is half the filtration story.

Run it that way and you'll get OEM-or-better filtration with the airflow advantage intact.

Should you run an S&B on a stock truck or a tuned truck?

Either works. The math is just a little different.

Stock truck: the gains are modest but real — slightly quicker spool, slightly better MPG, much better filtration and sound. Worth doing for the daily-driver upgrades you actually notice and for the long-term engine health.

Tuned truck: here the case gets stronger. Tuning fueling without addressing airflow is leaving power and EGT margin on the table. An S&B is one of the cheapest pieces of the supporting-mod puzzle and one of the first parts experienced builders bolt on.

Either way, if you're not sure where your truck stands or which intake matches your tune and platform, drop us a line via our quote page — we'll match you to the right unit.

Frequently asked questions

Are cold air intakes worth it on a diesel?

Yes — more than on a gas engine. Cooler, less-restricted air gives you better turbo response, slightly more power, slightly better fuel economy, lower EGTs, and dramatically better filtration. It's not a 100-HP mod, but it's a real one that you feel every day.

Will an S&B intake increase MPG on my diesel?

Usually a small, measurable bump. The bigger MPG impact comes from less restricted airflow paired with other upgrades. Don't buy it expecting double-digit MPG gains — buy it for the combined benefits.

Does a cold air intake help a diesel?

Yes — particularly in turbo response, sound, and filtration. The power gain is modest but real; the day-to-day driving impact is more noticeable than the dyno number suggests.

What does a cold air intake do for a diesel?

Replaces the restrictive OEM airbox with a higher-flow, better-filtering system that pulls cooler, denser air into the turbo. The result is improved spool, slightly more power, and a much-improved engine-bay package.

Are cold air intakes bad for diesel trucks?

A correctly installed, quality intake (like an S&B) is not bad for your truck — it's a filtration improvement over OEM. The bad reputation comes from old over-oiled cotton filters on poorly designed kits in the gasser world.

Cotton or dry — which S&B filter is better?

Cotton flows slightly more and needs periodic oiling. Dry PowerStack is nearly as high-flow, never needs oil, and is essentially set-and-forget. Pick the one that matches the maintenance routine you'll actually keep up with.

Will an S&B intake require a re-tune?

No — the truck's ECU will adapt to the new airflow without any retuning. If you've already got a custom tune, the intake stacks with it nicely; if you're stock, you're good to go right out of the box.

How long does an S&B intake last?

The housing and tube are essentially lifetime parts — they're built to outlast the truck. The filter is the consumable; service it on schedule and the same filter lasts well past 100,000 miles of normal use. Replacement filters are always available.

Can I run an S&B intake on a brand-new truck?

Yes. There's no break-in requirement and no waiting period. Many owners bolt one on within the first week of ownership.

Is an S&B intake CARB-legal?

Many S&B intakes carry CARB Executive Order numbers for specific applications, which makes them street-legal in California and other CARB-following states. Always check the specific kit's EO status for your year and platform on the product page — and if you're unsure, just ask us before you order.

Get one breathing right

An S&B intake is the rare upgrade where the marketing pitch and the in-truck reality actually line up. Better airflow, better filtration, better sound, real (if modest) gains. The dollars-per-smile ratio is excellent.

Shop the full S&B Filters collection at DNR Customs, browse the rest of the air intakes & filters category to round out your build, and if you want a human to pick the right intake for your year, platform, and the rest of your mod list, request a quote — we'll spec it right the first time, every time.