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Monday 8am - 1pm 2pm - 5pm Tuesday 8am - 1pm 2pm - 5pm Wednesday 8am - 1pm 2pm - 5pm Thursday 8am - 1pm 2pm - 5pm Friday 8am - 1pm 2pm - 5pm

Hillside Auto Repair

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O'Fallon, MO
Hillside Auto Repair

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Loved by O'Fallon since 1985! 🚗 Hillside Auto Repair: The Professionals You Can Trust for expert service and honest advice.

All backed by a nationwide 3 yr/36k mile warranty. Your family deserves the best - we deliver!

10/20/2026

Is your oil light playing peek-a-boo with you at every stoplight? 🚦

That flicker is not just a friendly hello. It could be a failing sensor, the wrong filter, or something much more serious. Ignoring it is a gamble you do not want to take. 🛑

Read our latest blog to find out why this happens and why you need the trusted professionals at Hillside Auto Repair in O'Fallon. We have been keeping engines safe since 1985.

🔗 Click the link to learn more:
👉https://hillsideautomotiverepair.com/blog/why-does-my-oil-pressure-light-flicker-at-idle

10/19/2026

🚨 O’FALLON, WE NEED TO TALK ABOUT YOUR TIRES! 🚨

Did Missouri's latest cold front make your tire pressure warning light come on? You're not alone! 🍂🥶

When temperatures drop, tire pressure drops with them. A 10°F temperature change can mean roughly 1 PSI difference, and that chilly October morning could be enough to light up your dashboard.

But before you blame Mother Nature and keep driving, remember that nails, leaks, and faulty tire pressure sensors can trigger that little yellow light, too.

🔧 At Hillside Auto Repair, we've been helping O'Fallon drivers keep their vehicles running right since 1985. From minor fixes to major repairs, professional-grade diagnostic equipment, comprehensive maintenance, and our 3-year/36,000-mile service warranty, we're here to take the guesswork out of car care.

We're The Professionals You Can Trust!

Because the only thing that should be falling this October is the temperature, not your tire pressure! 😆

CLICK THE LINK to read our latest blog and learn why the Midwest's changing weather is putting the pressure on your tires, what you should check, and when it's time to call a professional.
👉 https://hillsideautomotiverepair.com/blog/why-is-everyone-s-tire-pressure-warning-light-coming-on

💬 Has your tire pressure light made an unexpected appearance this week? Tell us in the comments!

10/15/2026

How Long Will Your Rebuilt Transmission Last? The Honest Answer. 🔧🚗

You need a transmission repair. You get three quotes, and they are all over the map. Why?

Because not all rebuilds are created equal. A cheap rebuild uses aftermarket parts and skips critical steps like flushing the cooler. It might last 10,000 miles. A quality rebuild uses OEM or OE equivalent parts, replaces all wear components, and addresses the root cause of the failure. It can last 100,000 miles or more.🤑

At Hillside Auto Repair, we have been the professionals you can trust in O'Fallon since 1985. We use the same tools and equipment that the dealership does, and we back our work with a 3-year, 36,000-mile warranty. Do not settle for a temporary fix.🧰

Click the link to read our full blog on how long a rebuilt transmission actually lasts! 👉https://hillsideautomotiverepair.com/blog/how-long-does-a-rebuilt-transmission-actually-last

Question for you: Have you ever had a transmission rebuilt? How long did it last? Tell us in the comments! 👇

10/14/2026

Where Is Your Oil Going? The Mystery Explained. 🔍🚗

Your oil level keeps dropping, but there is no puddle in the driveway. What is going on? 😵‍💫

Oil does not just disappear. It is going somewhere. It could be slipping past worn valve stem seals, sneaking past tired piston rings, or being pulled through a failed PCV system into the intake. 💥

The symptoms tell the story. A puff of blue smoke on cold start points to valve seals. Smoke under acceleration points to piston rings. Silent consumption points to the PCV system.

At Hillside Auto Repair, we have been the professionals you can trust in O'Fallon since 1985. We perform consumption tests, leak down tests, and thorough inspections to find the source. We use the same tools and equipment that the dealership does, and we back our work with a 3-year, 36,000-mile warranty.

Click the link to read our full blog on why your engine uses oil but never leaks!
👉https://hillsideautomotiverepair.com/blog/the-mystery-of-the-vanishing-oil-where-does-it-all-go

Question for you: Has your engine ever developed a mysterious oil habit?

What did you find out? Tell us in the comments! 👇

10/13/2026

New Battery, New Problems? We Can Explain. 🔋🚗

You replaced your battery. Now your car is idling rough, shifting weird, and your windows have a mind of their own. What is going on? 😨

Your vehicle's computers have memory, and when you cut the power, they forget how to behave. Idle relearns, transmission relearns, window resets, and steering angle calibrations are all part of a proper battery replacement on a modern vehicle.

At Hillside Auto Repair, we have been the professionals you can trust in O'Fallon since 1985. We use the same tools and equipment that the dealership does, and we back our work with a 3-year, 36,000-mile warranty. Do not settle for a half finished job.🧰

Click the link to read our full blog on why your car needs a relearn after a battery replacement! https://hillsideautomotiverepair.com/blog/the-battery-swap-that-started-a-rebellion

Question for you: Have you ever had weird electronic issues after a battery change? Tell us about it in the comments! 👇

10/08/2026

Ever wonder why your engine feels like a rockstar one day and a sleepy sloth the next? 🎸➡️🦥

It might be your Variable Valve Timing system, and the culprit could be as simple as dirty oil. We wrote a deep dive on how oil pressure literally changes your engine's personality, plus why your Adaptive Cruise Control is secretly eating your brake pads for breakfast. 🛑🔧

If you're in O'Fallon, Missouri, you need a shop that speaks fluent engine and doesn't charge dealership prices. Hillside Auto Repair has been the trusted name since 1985. We use the same tools as the dealership, offer a 3-year/36,000-mile warranty, and we actually explain what's going on under your hood.

Click the link to read the full blog and learn how to keep your ride feeling like its best self. 👉https://hillsideautomotiverepair.com/blog/what-is-variable-valve-timing

Your car will thank you, and your wallet might too. 🚗💨

10/07/2026

Ever heard a shop recommend a "fuel induction service" and wondered if you were about to get hosed?🤑

Same. But here is the tea. Carbon buildup is real, especially in modern direct injection engines, and it can wreck your fuel economy, idle quality, and acceleration. The catch?

Not every car needs it, and not every shop is honest about that. We wrote a whole blog breaking down when this service is legit, when it is a waste, and how to spot the difference.

We have been O'Fallon's trusted shop since 1985, and we do not do wallet flushes. We do honest diagnostics and real fixes backed by a 3 year 36,000 mile warranty.

Click the link to read the full breakdown and find out if your ride actually needs some intake TLC. 👉https://hillsideautomotiverepair.com/blog/why-do-i-need-a-fuel-induction-service

Your engine will thank you. Probably. Engines are not great at thank you notes.

10/01/2026

We love a good DIY mechanic, but even the best of us get that "UH OH" look when electrical problems strike. 🦌⚡️

Mechanical? You got this. Electrical? That's our jam. At Hillside Auto Repair, we have the diagnostic tools and the know-how to solve even the most confusing electrical mysteries. Don't waste hours chasing wires, let the experts handle it!

📞 Ready to get it fixed right? Call Nikki at 636-240-1050 and schedule your appointment today. We promise, the only dog faces around here is our Shop Dog, Princess! 🐾

09/30/2026

Let’s be honest: YouTube makes car repair look easy. The reality? Sometimes it looks like this meme. 🤷‍♂️

If you’ve reached the "soot-covered and confused" stage of your weekend project, it's time to wave the white flag. Save your eyebrows and your budget, bring it to Hillside Auto Repair. We have the tools, the training, and the fire extinguisher. 🧯

Call and schedule with Nikki today: 636-240-1050

09/22/2026

Can you mix synthetic and conventional oil? Sure. You can also wear socks with sandals. Both are technically possible and both make mechanics cringe. 😨

The chemistry will not cause an explosion, but it will leave your engine running on a compromised blend that protects it less and wears it faster. 💥

Here at Hillside Auto Repair in O'Fallon, we have been the professionals you can trust since 1985. We offer comprehensive auto repair services, dealership level tools, a 3 year, 36,000 mile warranty, and zero judgment. 🧰

Click the link to read our full blog on the chemistry of base stocks and why mixing is not the move. Your engine will thank you, probably with fewer weird noises.

👉https://hillsideautomotiverepair.com/blog/can-you-mix-synthetic-and-conventional-oil

Your engine has enough to worry about without you playing mad scientist in the driveway. 🧑‍🔬

When was the last time you checked your oil, and do you actually know what is in there right now?

Address

400 Church Street
O'Fallon, MO
63366

Opening Hours

Monday	8am - 1pm
	2pm - 5pm
Tuesday	8am - 1pm
	2pm - 5pm
Wednesday	8am - 1pm
	2pm - 5pm
Thursday	8am - 1pm
	2pm - 5pm
Friday	8am - 1pm
	2pm - 5pm

Telephone

+16362401050

Website

http://www.hillsideautomotiverepair.com/

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