How can you keep your fleet cool and reliable in summer?

Picture this: it’s early June, and you’re thinking ahead. Summer’s just around the corner, and you know what’s coming—the heat, the breakdowns, the chaos. You’ve got a choice to make right now: invest a few hours in maintenance this week, or deal with emergency breakdowns in July and August when your fleet is at maximum capacity.

Here’s the thing—summer breakdowns aren’t inevitable. They’re the result of skipping maintenance right now, in early June, when you still have time to prepare. And honestly? That’s the easy part to fix.

In this guide, we’re going to walk through exactly what you need to do to keep your fleet running smoothly when the heat’s on (literally). We’re talking real-world strategies, not generic checklists. By the end, you’ll know precisely what to check, when to check it, and why it actually matters to your bottom line.

Key Takeaways

• Summer heat places additional strain on vehicle cooling systems, engines, and fluid levels
• Regular checks of coolant, air conditioning, and fluid levels are essential before summer arrives
• Overheating vehicles can lead to costly breakdowns, reduced fuel efficiency, and safety hazards
• Preventative maintenance during summer can save fleets thousands in emergency repairs
• Proper tyre pressure management and battery checks are often overlooked but critical in hot weather

Why Summer Maintenance Matters for Your Fleet

The Impact of Heat on Vehicle Performance

Let’s be honest—summer is brutal on vehicles. Your engine’s cooling system is designed to maintain a specific temperature. In winter, it’s got an easy job. In summer? It’s fighting a losing battle against 25–30°C+ ambient temperatures.

Think of it like this: your cooling system is designed to shed heat. In winter, the outside air is cold, so heat transfers away easily. In summer, you’re trying to push heat into air that’s already hot. It’s like trying to cool down by jumping into a warm swimming pool.

Now add urban traffic into the mix. Your vehicle’s idling in congestion, airflow through the radiator drops to almost nothing, and the cooling system is working at absolute maximum capacity. One weak link—a partially blocked radiator, low coolant, a failing thermostat—and boom. You’ve got an overheating engine. In fact, cars are 50% more likely to overheat, making it one of the leading causes of breakdowns on UK roads.

And it’s not just the engine. Heat affects everything. Your battery? It’s working harder. Your tyres? They’re expanding, which can lead to blowouts if pressures aren’t monitored. Your transmission fluid? It’s getting thinner, losing its protective properties. Summer doesn’t just stress one system—it stresses everything simultaneously.

The Cost of Neglect

Here’s where it gets real. A single breakdown during summer doesn’t just cost you money—it costs you credibility, customer satisfaction, and peace of mind. Unplanned downtime can cost £450–£760 per vehicle, and that’s just the start.

Let’s say one of your vehicles overheats on a summer afternoon. What happens?

• Recovery truck arrives: £300–£500
• Tow to nearest garage: included
• Engine damage assessment: £100–£200
• Actual engine repair: £2,000–£5,000
• Vehicle downtime: 1 week minimum
• Lost deliveries: £1,000–£3,000 in revenue
• Angry customers: Priceless (and damaging)

That’s roughly £4,000–£9,000 for one vehicle. Now multiply that across your fleet. If you manage 10 vehicles and experience just one breakdown per vehicle over summer, you’re looking at £40,000–£90,000 in costs.

Compare that to preventative maintenance: £150–£300 per vehicle, or £1,500–£3,000 for your entire fleet. Research shows that fleets can save £15,000–£25,000 annually by shifting from reactive to preventive maintenance. Suddenly, that maintenance budget looks like the best investment you’ll make all year.

Essential Summer Maintenance Checks

Coolant System Inspection: Your First Line of Defence

Your coolant system is basically your vehicle’s life support system in summer. It’s the difference between a smooth day and a breakdown on the hard shoulder.

Before summer arrives, have a proper coolant system inspection. Here’s what your mechanic should check:

Coolant level and condition: This is the obvious one, but it’s crucial. Low coolant means your cooling system can’t do its job. But here’s what most people miss—the condition of the coolant matters just as much as the level.

Coolant degrades over time. It loses its ability to protect against corrosion and boiling. If your coolant looks dark, murky, or rusty instead of bright red or green, it’s telling you something’s wrong. It’s essentially saying, “I’m not protecting your engine anymore.” That’s when you need a full system flush. According to RAC guidance on car overheating, regular coolant checks are essential to preventing summer breakdowns.

Radiator condition: Your radiator is basically a heat exchanger. Hot coolant flows through it, and air flows across the fins to carry heat away. Sounds simple, right? Except those fins get clogged with dirt, debris, and dead insects. When that happens, heat can’t escape. Your radiator becomes less effective, and your cooling system has to work harder.

A visual inspection often reveals these issues. Look for visible blockages or corrosion. In some cases, a professional radiator flush removes internal deposits that restrict flow. It’s not glamorous work, but it’s absolutely necessary.

Hose integrity: Squeeze your coolant hoses gently. They should feel firm but slightly flexible. If they’re hard and brittle, they’re ready to fail—probably at the worst possible moment. If they’re soft and mushy, internal deterioration is happening. Either way, they need replacing before summer.

Thermostat function: Your thermostat is like the temperature control dial on your oven. It opens and closes to maintain the engine’s operating temperature. If it sticks open, your engine never reaches proper operating temperature. If it sticks closed, your engine overheats. A mechanic can test this during a service.

Here’s the bottom line: don’t just top up coolant and hope for the best. Get a proper inspection. It takes an hour and costs £60–£100. It could save you thousands.

Air Conditioning System Service: Because Comfort Matters

You might think AC is just about keeping drivers comfortable. You’d be wrong. A functioning AC system directly impacts driver safety and alertness.

Think about it—a driver working in a hot cab is uncomfortable, fatigued, and less alert. Their reaction times slow down. They make mistakes. They’re more likely to speed or take risks. That’s a safety issue, not just a comfort issue.

During summer, your AC system needs serious attention:

Test AC performance: The AC should blow noticeably cold air within 30 seconds of starting the vehicle. If it takes longer or never gets truly cold, there’s a problem. Don’t ignore it.

Check refrigerant levels: A pressure test reveals refrigerant levels. Here’s something most people don’t know—even a perfectly sealed system loses a small amount of refrigerant annually (around 5–10%). That’s normal. But if you’re losing more than that, there’s a leak. Topping up refrigerant without finding the leak is like bailing out a boat without plugging the hole.

Inspect compressor function: Listen carefully. A healthy AC compressor is nearly silent. If you hear grinding, squealing, or clicking noises, something’s wrong. These noises suggest internal wear or electrical issues. Don’t wait—have it checked.

Clean or replace cabin air filters: This is the one everyone forgets. A clogged cabin air filter forces the AC system to work harder, reducing cooling performance and increasing fuel consumption. Cabin air filters typically cost £15–£30 and take 10 minutes to replace. It’s a no-brainer maintenance task.

If your AC isn’t performing well, have it serviced before the summer rush begins. An AC failure in July is far more expensive than a service in May. Trust me on this one.

Fluid Level Checks: The Weekly Ritual

Summer heat causes fluid levels to drop faster than in cooler months. This isn’t optional—make it a weekly ritual.

Engine oil: High temperatures thin oil, reducing its protective properties. Check your oil level weekly during summer. Maintenance costs range from £0.20 to £1.10 per mile depending on vehicle age and maintenance strategy—a gap that proper oil management can help close. Here’s a pro tip: consider switching to a higher-viscosity oil if recommended by your vehicle manufacturer. If your vehicle normally uses 10W-30 oil, summer operation might benefit from 10W-40. It’s thicker, so it maintains better protection at higher temperatures.

Always consult your owner’s manual before changing oil viscosity. Different engines have different requirements.

Transmission fluid: Low transmission fluid causes shifting problems and overheating. Here’s how to check: transmission fluid should be bright red and smell slightly sweet. Dark, burnt-smelling fluid means the transmission is overheating and needs service immediately. Don’t ignore this one.

Power steering fluid: Essential for smooth steering, especially in stop-and-go traffic. Low power steering fluid makes steering heavy and difficult. Check levels with the engine warm and the steering wheel straight.

Brake fluid: Moisture absorption increases in humid summer conditions. Brake fluid absorbs moisture from the air. In summer humidity, this happens faster. Moisture in brake fluid lowers its boiling point, which can cause brake fade in heavy braking situations. Consider a brake fluid flush to remove old fluid and moisture.

Make these checks part of your weekly routine during summer. It takes 15 minutes and can prevent major problems. Seriously—set a calendar reminder for every Monday morning.

Tyre Pressure and Condition: The Overlooked Critical

Heat expands air inside tyres, increasing pressure. Overinflated tyres wear unevenly and are prone to blowouts. Underinflated tyres generate excess heat and increase fuel consumption. It’s a delicate balance.

Check tyre pressure weekly during summer months. Here’s the physics: tyre pressure increases by approximately 1 PSI for every 5°C increase in temperature. A tyre that’s properly inflated at 20°C will be overinflated at 30°C. Check pressure when tyres are cold (before driving) for the most accurate reading.

Inspect tread depth to ensure adequate grip. Worn tyres are more prone to blowouts in hot weather. Use the penny test: insert a penny into the tread with the Queen’s head upside down. If you can see the top of her head, tread is too shallow. Professional tyre depth gauges are more accurate and worth the investment.

Look for signs of wear or damage: Bulges, cracks, or uneven wear patterns are red flags. Bulges suggest the tyre’s internal structure is failing—it could blow out at any time. Cracks indicate dry rot, common in older tyres exposed to UV. Uneven wear suggests alignment or pressure issues.

Rotate tyres regularly to promote even wear. Front tyres wear faster than rear tyres due to steering loads. Rotating tyres every 10,000 km extends their lifespan and improves safety.

Battery Testing: The Silent Killer

Summer heat accelerates battery deterioration. A battery that seems fine in winter may fail unexpectedly in summer. It’s like the battery is running a marathon in the heat—it gets exhausted faster.

Test battery voltage and load capacity before summer. A healthy battery should measure around 12.6 volts when the engine is off. Under load (cranking the engine), voltage should stay above 10 volts. A battery tester can measure this accurately. Most garages offer this service for free or a small fee.

Clean battery terminals to ensure good electrical connections. Corrosion (white, blue, or green crusty deposits) increases resistance and reduces electrical flow. Mix baking soda and water to clean terminals, then dry thoroughly. It takes 5 minutes and makes a real difference.

Check battery mounting to ensure it’s secure and won’t vibrate loose. A loose battery can damage internal connections and cause electrical problems.

Replace batteries that are more than three years old. Even if they’re working now, they’re approaching the end of their lifespan. Summer heat accelerates failure. Replacing a battery proactively costs £80–£150. An emergency roadside battery replacement costs £200–£400 plus recovery fees. Do the maths.

Summer Driving Habits That Protect Your Fleet

Avoid Unnecessary Idling: The Heat Killer

Idling in hot weather causes engines to work harder and coolant systems to strain. It’s one of the worst things you can do to a vehicle in summer.

Encourage your drivers to turn off engines when parked, rather than leaving them running. An idling engine produces no power but consumes fuel. Worse, in summer heat, an idling engine can overheat if airflow through the radiator is insufficient. Modern engines can be restarted without damage—the old myth about restarting damaging engines is completely false.

Avoid prolonged idling in traffic. If traffic will be stopped for more than 30 seconds, turn off the engine. This saves fuel and reduces heat stress. It’s that simple.

Use air conditioning judiciously—it increases engine load. AC systems consume engine power. In heavy traffic where the engine is already stressed, running AC at maximum increases the risk of overheating. Drivers should use AC as needed for comfort and safety, but avoid unnecessary maximum settings.

Monitor Driving Patterns: Smooth Wins

Aggressive driving—rapid acceleration, hard braking, speeding—generates excess heat. It’s like revving your engine to the max constantly. Everything gets hotter.

Implement driver training programmes that emphasise smooth, steady driving to reduce heat stress on engines and brakes. Rapid acceleration forces the engine to work at high RPM, generating excess heat. Hard braking generates friction heat in the brake system. Speeding increases aerodynamic drag and engine load.

Smooth, steady driving keeps the engine at moderate RPM, reduces brake stress, and improves fuel efficiency. It also reduces wear and tear on all vehicle systems. Consider implementing a driver incentive programme that rewards smooth driving. Telematics systems can track driving behaviour and identify aggressive drivers for coaching.

Here’s the kicker—drivers who drive smoothly also have fewer accidents. It’s a win-win.

Plan Routes Strategically: The Smart Approach

During peak summer heat, think strategically about routing:

Schedule deliveries during cooler morning or evening hours when possible. Morning and evening temperatures are typically 5–10°C cooler than midday temperatures. This reduces cooling system stress and improves driver comfort. Your drivers will thank you, and your vehicles will thank you even more.

Avoid routes with excessive traffic congestion. Idling in traffic generates heat. Routes with fewer traffic lights and smoother traffic flow reduce heat generation. Use GPS routing software that accounts for traffic patterns. It’s worth the investment.

Build in extra time so drivers aren’t rushed and tempted to drive aggressively. Time pressure encourages speeding and aggressive driving. Realistic schedules allow drivers to operate vehicles smoothly and safely. Plus, your customers appreciate on-time deliveries more than early ones anyway.

Preventative Maintenance Schedule for Summer

Pre-Summer Preparation (May): The Critical Window

Before summer arrives, conduct a full inspection. This is non-negotiable. Think of it as your vehicle’s summer passport—without it, you’re not going anywhere.

Schedule this maintenance in late May, before summer heat peaks and before your fleet enters its busiest season. This ensures vehicles are in peak condition when you need them most.

What should this inspection include?

• Coolant system flush and refill
• Air conditioning service
• Battery test and replacement if needed
• Tyre rotation and pressure check
• Fluid level top-ups
• Brake inspection

Budget 4–6 hours per vehicle for this work. Yes, it’s time-consuming. Yes, it’s worth every minute.

Mid-Summer Check (July–August): The Maintenance Pulse

During peak summer, perform monthly checks. Think of these as health checks for your vehicles.

• Coolant and fluid levels
• Tyre pressure (weekly)
• Battery condition
• Air conditioning performance
• Brake pad wear

These checks take 30–45 minutes per vehicle and can catch problems before they become breakdowns. It’s the difference between a £100 fix and a £5,000 breakdown.

Post-Summer Review (September): The Debrief

As temperatures cool, assess what worked and what didn’t. This is where you learn for next year.

• Review breakdown records
• Identify vehicles that had issues
• Plan preventative measures for next summer
• Schedule any necessary repairs

Document which vehicles had problems and why. This information helps you identify patterns and plan better maintenance for next year. If the same vehicle keeps overheating, there’s a systemic issue that needs addressing.

Technology and Tools for Summer Fleet Management

Telematics Systems: Your Eyes in the Sky

Modern telematics systems monitor vehicle health in real time, alerting you to problems before they become catastrophes.

These systems can alert you to:

• Engine temperature anomalies
• Fluid pressure warnings
• Battery voltage drops
• Tyre pressure changes

Early alerts allow you to address problems before they become breakdowns. For example, if a vehicle’s coolant temperature begins rising abnormally, the system alerts you immediately. The driver can pull over and allow the engine to cool before serious damage occurs.

Telematics systems also provide historical data. You can see which vehicles consistently run hot, which have battery issues, and which have tyre pressure problems. This data guides maintenance decisions. If one vehicle keeps running hot, there’s a cooling system problem that needs addressing.

Maintenance Management Software: The Organised Approach

Centralised maintenance scheduling ensures no vehicle is overlooked. It’s like having a personal assistant for your fleet.

These systems provide:

• Automated reminders for service intervals
• Digital maintenance records
• Cost tracking and analysis
• Historical data to identify patterns

When a vehicle is due for service, the system sends an alert. Maintenance staff can schedule the service immediately rather than relying on memory. Digital records ensure nothing is forgotten.

Driver Monitoring Tools: The Coaching Opportunity

Some systems track driver behaviour, identifying aggressive driving patterns that increase heat stress on vehicles. Drivers who consistently accelerate hard, brake hard, or speed can be identified and coached on smoother driving techniques.

This isn’t about punishment—it’s about coaching. Drivers who understand why smooth driving matters are more likely to adopt better habits.

Common Summer Vehicle Problems and Solutions

Overheating: The Nightmare Scenario

Problem: Engine temperature gauge in the red zone

Causes: Low coolant, faulty thermostat, blocked radiator, failed water pump

Solution: Stop safely, allow engine to cool, check coolant level, have system inspected before driving further

If a vehicle overheats, don’t panic. Pull over safely, turn off the engine, and allow it to cool for at least 15 minutes. Never open the radiator cap when hot—you risk severe burns from boiling coolant. Seriously, don’t do it.

Once cooled, check the coolant level. If it’s low, top it up with the appropriate coolant for your vehicle. If the level is normal, there’s likely a more serious problem (thermostat, water pump, or radiator issue). Have the vehicle towed to a mechanic rather than risking further damage by driving it.

Air Conditioning Failure: The Comfort Crisis

Problem: AC blows warm air or stops working entirely

Causes: Low refrigerant, compressor failure, electrical issues

Solution: Have AC system serviced by a qualified technician; avoid DIY repairs

AC systems are complex and require specialised equipment to diagnose and repair. Attempting DIY repairs can cause more damage. Have a qualified technician diagnose the problem. In the UK, refrigerant handling requires F-Gas certification—only certified technicians can legally handle refrigerants.

Battery Failure: The Unexpected Shutdown

Problem: Vehicle won’t start or starts sluggishly

Causes: Battery age, corroded terminals, alternator issues

Solution: Test battery load capacity; replace if necessary; clean terminals

If a vehicle won’t start, the battery is the first suspect. A battery tester can determine if the battery is the problem or if there’s an alternator issue. If the battery is more than three years old, replacement is usually the best option.

Tyre Blowouts: The Dangerous Surprise

Problem: Sudden tyre failure whilst driving

Causes: Overinflation, underinflation, worn tread, road hazards

Solution: Maintain proper tyre pressure; inspect tyres regularly; replace worn tyres before summer

Tyre blowouts are dangerous and can cause loss of vehicle control. Prevention is far better than dealing with a blowout on a busy motorway. Check tyre pressure weekly, inspect for damage regularly, and replace worn tyres before summer.

Best Practices from Leading Fleet Operators

Proactive Maintenance Culture: The Mindset Shift

Successful fleet managers treat maintenance as an investment, not an expense. A complete maintenance program guide shows that structured maintenance strategies deliver measurable ROI. They understand that £1 spent on prevention saves £5 on emergency repairs.

They:

• Schedule preventative maintenance during off-peak periods
• Keep detailed maintenance records
• Invest in driver training to reduce wear and tear
• Monitor fuel efficiency as an indicator of vehicle health

Fuel efficiency is a useful indicator of vehicle health. If a vehicle’s fuel consumption suddenly increases, something’s wrong. It might be underinflated tyres, a clogged air filter, or engine problems. Monitoring fuel efficiency helps identify problems early.

Supplier Partnerships: The Relationship Advantage

Building strong relationships with trusted maintenance providers ensures:

• Priority scheduling during busy seasons
• Consistent service quality
• Competitive pricing through volume agreements
• Expert advice on fleet-specific issues

Don’t shop purely on price. A slightly more expensive provider who knows your fleet and prioritises your vehicles is worth the investment. During summer when everyone needs maintenance, a good relationship ensures your vehicles get serviced promptly.

Cost-Benefit Analysis: Summer Maintenance Investment

Cost of Preventative Maintenance

A comprehensive summer maintenance programme typically costs £150–£300 per vehicle, depending on the work required. For a fleet of 10 vehicles, that’s £1,500–£3,000 for the entire fleet.

This includes:

• Coolant system inspection and top-up: £40–£80
• AC service: £60–£120
• Battery test: £20–£40
• Tyre rotation and pressure check: £30–£60
• Fluid level checks and top-ups: £20–£40
• Brake inspection: £30–£60

Cost of Reactive Repairs

A single engine overheating incident can cost £500–£2,000 in repairs, plus lost productivity. Multiply this across a fleet, and the costs become staggering.

• Emergency roadside repair: £150–£300
• Engine damage repair: £500–£2,000
• Vehicle recovery: £200–£400
• Lost productivity: £500–£1,000 (depending on vehicle and job)
• Customer dissatisfaction: Immeasurable

Return on Investment

For most fleets, every £1 spent on preventative maintenance saves £3–£5 in emergency repairs and downtime. Preventive maintenance delivers the strongest ROI, with scheduled service consistently reducing breakdowns, downtime, and long-term repair costs. Over a summer season, this translates to significant savings.

If preventative maintenance costs £2,000 for your fleet and prevents even one major breakdown, you’ve saved £1,500–£3,000. Research shows that predictive maintenance reduces unexpected breakdowns by 40%, making the ROI substantial.

Preparing Your Team for Summer

Driver Training: The Knowledge Advantage

Ensure all drivers understand:

• How to recognise warning signs (temperature gauge, warning lights, unusual sounds)
• What to do if a vehicle overheats
• The importance of reporting maintenance issues immediately
• Fuel-efficient driving techniques that reduce heat stress

A driver who recognises an overheating engine early can pull over and prevent serious damage. A driver who ignores warning signs risks catastrophic engine damage. Invest time in driver training—it pays dividends.

Run a quick 15-minute training session with your drivers in May. Show them what warning signs to look for. Explain why smooth driving matters. Give them permission to pull over if something feels wrong. These conversations matter.

Maintenance Team Readiness: The Preparation Phase

Your maintenance team should:

• Be trained on summer-specific issues
• Have adequate stock of coolant, filters, and other consumables
• Have clear protocols for emergency repairs
• Be prepared for increased workload during peak summer months

Stock up on consumables in May before the summer rush. Running out of coolant or filters during peak summer creates delays. Having adequate inventory ensures smooth operations.

Conclusion

Summer maintenance isn’t optional—it’s essential to keeping your fleet safe, reliable, and profitable. By investing in preventative measures now, you’ll avoid costly breakdowns, reduce downtime, and extend vehicle lifespan.

Your drivers will appreciate working with well-maintained vehicles. They’ll feel safer, be more comfortable, and deliver better service to your customers. Your bottom line will thank you. And honestly? You’ll sleep better knowing your fleet is ready for whatever summer throws at it.

Start your summer maintenance programme today. Your fleet—and your business—will be better for it. And that’s not just maintenance talk—that’s a promise.

FAQ: Summer Fleet Maintenance

How often should I check coolant levels during summer?

Check coolant levels at least weekly during summer months. More frequent checks are advisable if your fleet operates in particularly hot climates or undertakes long journeys. Some fleets check daily during peak summer heat. Set a calendar reminder—it takes two minutes.

Can I use a different coolant type in summer?

Always use the coolant type specified by your vehicle manufacturer. Mixing different coolant types can reduce effectiveness and damage the cooling system. Check your owner’s manual for the correct coolant type. If you’re unsure, ask your mechanic. It’s not worth guessing on this one.

What’s the ideal tyre pressure for summer driving?

Follow the tyre pressure recommendations on your vehicle’s door jamb or in the owner’s manual. Adjust for temperature changes, but never exceed the maximum pressure listed on the tyre itself. Remember that tyre pressure increases with temperature—a tyre properly inflated at 20°C will be overinflated at 30°C. Check pressure weekly.

Is it safe to drive with the air conditioning on at maximum?

Whilst safe, running AC at maximum increases engine load and fuel consumption. Use it as needed for comfort and safety, but avoid unnecessary maximum settings. In heavy traffic where the engine is already stressed, moderate AC usage is wise. Your fuel bill will thank you.

How can I tell if my battery is failing?

Signs include slow engine cranking, dim headlights, clicking sounds when turning the key, or a battery warning light on the dashboard. Have the battery tested if you notice any of these signs. A battery tester provides a definitive answer. Don’t ignore these warning signs.

Should I change my oil before summer?

Consult your vehicle manufacturer’s recommendations. Some vehicles benefit from a higher-viscosity oil in summer, whilst others don’t require a change. Check your owner’s manual or ask your mechanic. It’s vehicle-specific, so don’t assume.

What should I do if a vehicle overheats whilst on the road?

Pull over safely, turn off the engine, and allow it to cool for at least 15 minutes. Never open the radiator cap whilst the engine is hot. Check coolant level once cooled, and have the vehicle inspected before continuing. Safety first—always.

How does summer maintenance differ from winter maintenance?

Summer focuses on cooling systems, fluid levels, and tyre pressure, whilst winter emphasises battery health, heating systems, and traction. Both seasons require proactive attention to different systems. Think of it as seasonal vehicle healthcare.

Can I perform summer maintenance myself?

Basic checks like fluid levels and tyre pressure can be done by fleet staff. However, coolant system flushes, AC service, and battery replacement should be handled by qualified technicians. Know your limits—some jobs need professionals.

What’s the best time to schedule summer maintenance?

Schedule maintenance in late May or early June, before peak summer heat and before your fleet enters its busiest season. This ensures vehicles are in peak condition when you need them most. Don’t wait until July—by then, it’s too late.