Es mejor que revises el neumático antes de salir.

Because es mejor que often introduces a recommendation, judgment, or advice, and that normally triggers the subjunctive in the next clause.

So:

• Es better that you check... → Es mejor que revises...

Here, the speaker is not stating a fact. They are giving advice about what should be done, so Spanish uses the subjunctive.

Compare:

• Revisas el neumático. = You check the tyre. / You are checking the tyre.
• Es mejor que revises el neumático. = It’s better that you check the tyre.

The second one is not a plain statement of fact, so revises is used.

In this structure, que links the main idea to the subordinate clause:

• Es mejor = It’s better
• que revises el neumático = that you check the tyre

So the pattern is:

• Es mejor que + subjunctive

Very common examples:

• Es importante que vengas. = It’s important that you come.
• Es bueno que descanses. = It’s good that you rest.
• Es mejor que revises el neumático. = It’s better that you check the tyre.

Yes. That is also correct, and it sounds very natural.

There is a small difference in focus:

• Es mejor que revises el neumático antes de salir.
  = It’s better that you check the tyre before leaving.
  This speaks more directly to you.

• Es mejor revisar el neumático antes de salir.
  = It’s better to check the tyre before leaving.
  This is more general and less directly aimed at a specific person.

Both are common. The version with que revises feels more like direct advice to someone.

Because Spanish usually does not need subject pronouns when the verb ending already makes the subject clear.

• revises already tells us the subject is tú in the present subjunctive.

So:

• Es mejor que revises el neumático... = normal
• Es mejor que tú revises el neumático... = possible, but more emphatic

You would add tú only if you want contrast or emphasis, for example:

• Es mejor que tú revises el neumático, no él.
  = It’s better if you check the tyre, not him.

Revises comes from the verb revisar = to check / inspect / go over.

This is the present subjunctive form for tú:

• yo revise
• tú revises
• él/ella/usted revise
• nosotros revisemos
• vosotros reviséis
• ellos/ellas/ustedes revisen

So in this sentence, revises means you check.

Because the subject of both actions is understood to be the same person.

• revises = you check
• salir = leaving, with the same subject implied

When the subject stays the same, Spanish usually uses:

• antes de + infinitive

So:

• Es mejor que revises el neumático antes de salir.

If the subject changes, Spanish usually uses:

• antes de que + subjunctive

Example:

• Es mejor que revises el neumático antes de que salga tu hermano.
  = It’s better that you check the tyre before your brother leaves.

So:

• same subject → antes de salir
• different subject → antes de que + subjunctive

Not exactly.

In Spain, neumático means tyre.
A rueda is more like wheel as a whole, though in everyday speech people sometimes use it loosely.

So:

• neumático = tyre
• rueda = wheel
• llanta = rim

In Spain, neumático is a standard word for tyre. A learner coming from Latin American Spanish may hear other words more often depending on the country, but neumático is completely normal in Spain.

Spanish often uses the singular when talking about one specific item or when the context makes it clear.

So el neumático can mean:

• a particular tyre
• the tyre that needs checking
• a tyre in a general practical situation

In real life, someone might also say:

• Es mejor que revises los neumáticos antes de salir.
  = It’s better to check the tyres before leaving.

That may be more logical if you mean all of them. But the singular sentence is still grammatically correct and natural.

Yes, basically. Salir usually means to go out or to leave.

In this sentence, antes de salir means:

• before leaving
• before setting off
• before going out

The most natural English translation depends on context. If this is about a car, before setting off or before leaving may sound best.

Yes, but the nuance changes a little.

• revisar = check / inspect / look over carefully
• comprobar = check / verify / make sure
• mirar = look at

For a tyre, revisar is a very natural choice because it suggests actually inspecting it.
Comprobar also works well if you mean checking pressure or condition.
Mirar is more general and can sound less thorough.

Examples:

• Es mejor que revises el neumático... = better if you inspect/check it
• Es mejor que compruebes el neumático... = better if you verify/check it
• Es mejor que mires el neumático... = better if you have a look at it

Because ser is used here to express a general judgment or evaluation:

• Es mejor... = It’s better...

This is not about a temporary state or condition, so estar would not fit.

Compare:

• Es mejor que revises el neumático. = It’s better that you check the tyre.
• El neumático está mejor ahora. = The tyre is better now.

So:

• ser = general assessment, quality, judgment
• estar = condition or state

A more direct command would be:

• Revisa el neumático antes de salir.
  = Check the tyre before leaving.

That is an imperative. It sounds more direct and straightforward.

The original sentence:

• Es mejor que revises el neumático antes de salir.

is softer. It sounds like advice rather than a direct order.

So the difference is roughly:

• Revisa... = direct instruction
• Es mejor que revises... = recommendation / advice

Yes, very common.

Spanish often gives advice with patterns like:

• Es mejor que + subjunctive
• Es importante que + subjunctive
• Conviene que + subjunctive
• Más vale que + subjunctive

Examples:

• Es mejor que descanses. = It’s better if you rest.
• Es importante que llegues a tiempo. = It’s important that you arrive on time.
• Conviene que revises el coche. = It’s advisable that you check the car.

So this sentence is a very useful model for giving polite advice.