Spring prep gets the RV out of storage. Summer prep gets it ready for heat, distance, and dust. The failures we see in July and August are different from the ones in April: tires that were fine at 60°F and delaminate at 110°F on the interstate, fridges that keep up in spring and lose the battle by noon in Arizona, and lithium banks that stop charging because the battery compartment hit its temperature limit. Work through this list two weeks before the trip, not the night before.
1. Tires, bearings, and brakes (the heat items)
Heat is what kills trailer tires. Ambient temperature plus road friction plus underinflation is the usual combination.
- Check pressure cold, against the placard, and add for load if the tire manufacturer specifies it. Buy a gauge you trust.
- Look at the date code. Trailer tires age out before they wear out; many manufacturers suggest replacement at five to seven years regardless of tread. Check the guidance your tire maker publishes. If you are due, the 15 in 235/75R15 ($240.00) and 16 in 265/75R16 off-road tires ($290.00) fit most HQ campers.
- Repack or at least inspect wheel bearings. A bearing that ran warm last season will fail on a long hot run. The Timken 12 in bearing ($29.00) and 10 in bearing ($25.00) are cheap insurance; the repack guide walks through it.
- Test the brakes on a quiet road and adjust. If they feel weak or grab, see the trailer brake troubleshooting guide.
- Test the breakaway switch. The CURT 12 V breakaway kit ($49.00) has an LED test light so you do not have to pull the pin.
- Carry a tire repair kit ($30.00), a lug wrench ($14.99) that fits your lugs, and wheel chocks ($18.00).
2. Fridge airflow
A compressor fridge that was fine in May will struggle in a 100°F campsite unless the condenser can dump heat. Before the trip:
- Pull the exterior vent cover and clean out dust, wasp nests, and lint.
- Confirm the fridge vent fan ($60.00) spins and comes on with temperature. If there is no fan, this is the single best summer upgrade for a fridge.
- Check the 12 V supply at the fridge under load. Low voltage is the most common cause of a fridge that "stops working" in summer; the fridge-on-12 V troubleshooting guide covers the test.
- Pre-cool the fridge on shore power the night before and load it with cold food.
3. Air conditioning and ventilation
- Run the rooftop A/C for an hour on shore power. Listen for the compressor cycling and check that air at the vent is cold. If the unit is old or was never enough, the Dometic Penguin II 15,000 BTU ($799.00) is the common HQ replacement; the 13,500 vs 15,000 BTU comparison helps you pick.
- Clean the return filter and the air distribution box louvers.
- A 12 V roof vent fan ($225.00) with the rain cover open moves more air overnight than most people expect and costs almost nothing in battery.
- Put an A/C cover ($25.60–$28.80) on for the highway if you are traveling through dust.
4. Power system in the heat
Lithium batteries stop charging above their high-temperature limit, which many quality units set around 122°F–140°F (50°C–60°C). Your battery's datasheet gives the figure that applies. A closed exterior battery box on a black trailer in the sun gets there.
- Check where the battery lives and whether it can breathe. Add a 12 V cooling fan ($17.99) to the compartment if temperatures are marginal; the equipment bay fan guide shows a simple install.
- Inverter/chargers derate in heat. A MultiPlus mounted in a hot locker will throttle output; give it the clearance the manual specifies.
- Look at the SmartShunt history and confirm the bank has actually reached 100% recently. A bank that has been sitting at 80% for months needs a full charge before you rely on it.
- Clean the solar panels. Pollen and dust cut output more than shade does on a long trip.
- Inspect every fuse holder and lug for green corrosion or heat discoloration, and torque them. Carry spares from the fuses collection.
5. Water: fill, filter, and keep it safe
- Sanitize the fresh tank if it sat with water in it. Drain, fill with a dilute bleach solution at the ratio on the product label, let it sit, and flush twice.
- Replace the inline filter. Warm water plus a filter that sat wet all spring is a bad combination. Options: the 6-layer 0.5 micron filter with stand ($139.99) or the reusable brass sediment filter ($69.00).
- Check the water pump runs, builds pressure, and shuts off. If it keeps cycling, fix it now; see water pump cycling.
- Run the tankless water heater and confirm ignition at low flow. Fit a water-saving shower head ($24.99) if you will be rationing water.
- Treat the black tank before the trip and carry tank treatment ($33.00); heat makes odor problems worse.
- Replace cracked quick-connect couplers ($9.99) and hose washers.
6. Seals, awning, and exterior
- Inspect the roof sealant and window seals. UV and heat open up cracks that let the first thunderstorm in.
- Run the awning out and back. Lubricate the arms. If the fabric is chalky or torn, see the awning replacement guide.
- Check window struts hold the windows open in the wind; carry a spare pair of OEM window struts ($25.00).
- Test every exterior light, especially tail lights and side markers.
7. Safety and propane
- Test the LP/CO detector ($42.00) and check its date. They expire.
- Check the fire extinguisher ($90.00) gauge.
- Leak-test propane fittings with soapy water after any regulator or hose change. The Flame King two-stage auto-changeover regulator ($34.99) is the usual replacement for a tired one.
8. Pack the summer spares kit
To the common-problems list add: a spare fridge vent fan, a spare tire (obviously), a 7-pin trailer plug ($19.99), a bag of stainless hose clamps ($8.99), and an extra gallon of drinking water per person per day beyond what the tank holds.
If you would rather hand this to someone, the Essential Annual Safety Service ($449.00) covers brakes, bearings, gas, and detectors in one visit.
Shop this
- 16 in Off-Road Tires 265/75R16 — $290.00
- Fridge Vent Fan — $60.00
- Dometic Penguin II 15,000 BTU Rooftop A/C — $799.00
- CURT 12V Trailer Breakaway Kit — $49.00
- 6-Layer RV Water Filter, 0.5 micron — $139.99
- Brakes, Suspension, Tire & Wheels (collection)