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How bad is driving my car through flooded streets?

In the aftermath of the hurricane the local streets around my house were flooded with up to a foot and a half of standing water. So whats the effects of driving through this water.
Theres been a debate going on between my neighbors on whether constant driving will damage the car or not. So some people have been drving (like myself) and some have refrained or have limited there trips. And I’m talking about regular sedans or small SUVs.

BTW nobody (including myself) has stalled out yet.

when the water dries up, change all your fluids(brake, trans, oil, radiator, differential, steering, etc). Then change them all again in a week or two to make sure any water that got in is gone

The worse case is that a hole opens up in the street and you can’t see it. Had one around here that ate a Mazda. A quick acting Samaritan saved the drivers life.

It’s hard to predict just how deep the water is going to get, or how deep is too deep. If you suck water into the air intake, you’ll ruin your engine.

It’s best to avoid driving through water, especially if you’re not sure how deep it will be.

Some cars have air intakes at the bottom of the engine bay to pick up cooler air. If you or your neighbors have such a car and get in too deep, you will suck water into the air intake and will probably destroy your engine.

It really depends on if it was salt water or fresh water. Salt water is bad, fresh water may be survivable!

I have drove car’s and truck’s thru deep water. As long as you don’t stall the car will be fine. You don’t need to change any fluids. If you stall or have to sit for a long time in over 1 foot of water then check the fluids for water. The vents are one way on axles. May or may not be on trans. The big thing is the brakes. Ride them a bit so they dry after you come out of the water. If it is salt water rinse the car good with fresh water as soon as possible. As stated you must know were the air intake is. If is low or high it can sill take in water.

I once drove a Toyota Tercel over a mile with water up to the hood. I drove slow and was following a 1 ton truck. We had no choice. The car ran fine after that. Brakes gave out 2 weeks later. But the brakes going out could have been due to were I driving. I was working in Puerto Rico at the time after one of the hurricanes and it was a rental.
Oh you will probable have problems with the Anti lock brakes sensors.

One more thing . When you are moving the air is trapped under the hood keeping the water from getting around the engine. Also don’t turn the car off right away. Let it run a few min’s to dry it and blow and dry out the muffler. That if you just came out of the water. Never drive in moving water. 1 foot of moving water can push a car off the road.

If the engine sucks in water…say good-bye to engine.

This practice is also the cause of failed suspension/steering components and wheel bearings. Any problem that occurs may not surface until months or years later and when that ball joint has failed or the wheel bearings are rumbling the car owner then assumes it’s due to a defective car at the worst or a worn part (which it is) at the least. They no longer equate that failure with the now forgotten underwater incident.

Boat trailers end up on the side of the highway for the same reason.

In my experience driving in deep mud and water, it all depends upon what you do later. Make sure you never let the vehicle sit and pay attention to lubricants. In cars that aren’t meant for deep water passage, it wouldn’t be a bad idea to change all lubricating fluids. Is it salt or fresh water flooding ? That makes a big difference too. I would worry about rust and “walk” the motor oil spray into body cavities as well.

With a foot of water, you need to be really careful. You could drive your car into a lake or sinkhole you aren’t able to see because it is obscured by the surface of the water.

If you are going to drive through this water regardless of the warnings, drive as slow as possible to keep water from splashing into the air intake.

I had to drive home in Miami during the last Hurricane Irene in 1999, and it was in more than a foot of water. It took me a really long time to get home, but when I finally made it, I had done no harm to my car. I am still driving that same car, and have had no issues with any suspension components.

While driving through water like this, it’s really frustrating to drive as slow as you have to drive to prevent damage, but in a case like this, you can’t go too slow. If you are driving an automatic, you will need to use the brake to control your speed since even at idle speed, you could easily go too fast.

If your car can survive driving in a heavy downpour, it can survive driving in a foot of water, just make sure you always control your speed. Drive as if you are in a boat in a “no wake” zone, but much slower. If you see any white caps in the wake you leave behind, you are going too fast. The wake you leave with your car should be extremely slow and gentle.

oldbodyman: “When you are moving the air is trapped under the hood keeping the water from getting around the engine.”

OMG, that has to be one of the most outlandishly BOOOOOOOGUS things I have ever heard. oldbodyman, what kind of car are you driving that has an air tight hood?

Even a small amount of water will ruin a transmission. A local industry had a flood in the employee’s parking lot. The water was up to the floor of pick ups and although most cars and trucks started and ran with no apparent damage with no indication of water contamination dozens of the vehicle’s transmissions failed within 100 miles. I repaired several and the transmission pans were full of clutch material. The transmission shop said that the water is absorbed by the clutches and when put under a load the water boils, vaporizes and disintegrates the clutch plates.

Thanks all for your advice and past experiences.
The water in my street is river water and not ocean (I live in central New Jersey).
It sounds to me that even if the car has survived up to this point I should have it checked out after the water finally drys. Specifically transmission and suspension.
I had flooding like this about 2 years ago (2009) and I was driving an 02 altima at the time and didn’t have any problems. But then back last July the transmission suddenly went out. Now I’m wondering if that was related?

I have drove 4X4 trucks and cars thru deep water. Have you? The hood on cars and trucks is sealed enough so that as you move thru the water a bubble of air forms and keeps the water away from the engine. Plus you have the wake affect. I have open the hood after driving thru deep water and saw no signs of water that has got on the engine. I once got stuck with a 4x4 in water up to the hood. When I stopped the water only then came out thru the hood gaps. I drive my Jeep in water a lot. If this was not so the distributor would get wet and the Jeep would not run. It is on the side of block. It is not sealed in any way.

Rod Knox you are right if a car sets in deep water. Water can get in to a transmission. But as I said as long as you are moving you will be ok. My 97 Chevy K1500 4X4 truck 322,000 miles, ball joints, steering components all original. Wheel bearing/hubs changed at just before 300,000 miles. This truck has been thru 3 hurricanes. Drove thru salt and fresh water. I just wash it good. Oh the trans was changed due a pice of metal that went thru the pan at about 265,000 miles. It was working good at the time and was original.

I have drove 4X4 trucks and cars thru deep water.

I have…And there’s no way in hell water’s NOT going to get in the engine compartment if it’s high enough…Not one 4x4 has a sealed hood that will create a air pocket to keep water out. I’ve driven F150’s…Army Jeeps…Pathfinders…GMC/Chevy pickups many times over streams/brooks.

But MY very first concern with cars and trucks these days it that air intake snout.
Sometimes deceivingly low to the ground for what one might assume.

If you know you’re going to drive in deep water…
First, open the hood and follow the air intake to learn just where the heck it goes and how low to the groung it is.

We’ve had hydrolocked engines in the shop from surprisingly low water levels.

We’ve hat hydrolocked engines in the shop from surprisingly low water levels.

Water doesn’t have to be the same level as the air intake. Splash a pint or two of water in the air-intake when it’s throttling…and it’ll be enough to hydrolock the engine.

Wow, oldbodyman is sticking to the “air pocket” theory, in spite of its obvious flaws. I’m amazed and bewildered.

I think I’m going to go out and buy a Polarity Pillow to protect me from harmful effects of aluminum.

In the late 40’s, we lived beside a small creek which in the spring melt became a raging river. To enter the bridge from the east when it was flooded, cars had to drive through the water. Since I was very small then, I cannot state it in feet or inches. It was deep on a little kid.

But, I can clearly tell you the cars would drive at a speed which pushed the water ahead of the car at the level of the hood, and they did not choke out. So, for that short distance, a few car lengths, at least, there was a bubble under the hood.


when we were young, all air intakes were on the top of the engine. Today, any are much lower to take advantage of cooler air below the car. Some cars may still have air intakes on top - certainly those with hood scoops do. But many don’t.