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Heavy Wheels

I was recently driving a friend’s car and noticed how easily it rolled when I let my foot off the accelerator. I drive a 2002 Hyundai Santa Fe V6 front wheel drive, and when I let my foot off the gas, the car immediately starts to decelerate. When driving down hill, or approaching a light, I sometimes shift into neutral and can coast with relatively low resistance. But as soon as I put the car back into drive, it seems to downshift suddenly. This is the only car I have ever owned and was resigned to the fact that maybe it was because I just drive a heavy car. But then I remembered a few years ago, I visited a different mechanic and whatever he did made the car seem to roll better, but now that feeling is gone.

Is there something on the engine, transmission or any other system that can be adjusted?

The transmission’s “logic” can be changed–to some small extent–by reflashing the TCM with updated software…IF updated software to eliminate these downshifts actually exists. The only one who could likely tell you if there is updated software for your transmission is the Hyundai dealership.

You cannot compare your friend’s car (whatever that is) to your Hyundai. How a car performs is an accumulation of countless details that vary from car to car.Comparing two different cars is analogous to comparing an elephant and a hippo. Both are large gray herbivores that like water, but the similarity ends there. They’re entirely, totally different animals that move and behave totally differently.

I agree with VDC that there might be some variation that the software will allow, but you can never expect to make your car behave like your friend’s.

By the way, what kind of car does your friend have?

Engine braking via the transmission can vary from one car to the other so you can’t compare 2 different makes. Both could be normal.

Only thing I would check is to make sure you didn’t accidentally turn off the overdrive, or somehow selected an awd or 4wd setting meant for slick/snowy roads. On some vehicles it’s done by pushing a button.

No 4wd on this old tank. But in comparison, I once rented a Kia Sorento and even drove my friends 2011 Grand Cherokee - that ride felt like I was floating. Both coasted with ease. The car I recently drove was a 2006 Nissan Sentra which made me cringe thinking about all the gas I must have wasted all these years.

It’s been a while since I’ve gotten service at the dealership, but since I only have about 120k, I think it might be worth a visit and get this software checked. Hopefully there will be an update.

Another possibility - a stuck/binding brake caliper, but that would tend to pull to one side or the other.

The differences might be as simple as different tires…or as complicated as differentdesign approaches to the different torque converters.

Is your tire pressure good?
Are your tires designed for low rolling resistance or good poor-weather traction?

If the pressure is good, the tires are all-weather or summer tires, and there are no wear, braking, or handling anomolies that would suggest a problem, and if your gas mileage is as advertised, than I’d be reluctant to mess with the tranny programming. Remember, every action has a reaction, and it isn;t always what we hope for.

Vehicles do vary widely, our Forester slows down much more than other vehicles I’ve driven when I let off the gas.

I thought it might be a caliper, and even thought it might have been parking break, but again, when I shift into neutral, I’m smooth sailing. And yes, I do use all-weather and probably over inflate anyway. 32psi makes the tires look too flat and gives it an even more sluggish ride.

UPDATE: I just got off the phone with the dealer and learned that I did in fact have my transmission replaced back in '04 (under warranty). Totally forgot about that! But according to the tech, there aren’t any program/firmware updates that he knows of.

So it’s either normal, or maybe something with the transmission. I’d guess the torque converter is staying locked up, but that would cause problems as you come to a stop, and you haven’t mentioned any.

its bad form to put your trans in neutral while driving

Is it in line?-Kevin

bscar2: why is it bad to drive in neutral with an automatic?

KMccune: Not sure what you mean in-line? In terms of alignments, I’ve had a number of those and the car stays true on a flat strait surface. I had a slow leak on one of my tires a while back and that kept shifting the car to one side. No longer the case here.

It is not just a bad idea to coast in neutral. In many states, it is actually illegal.

Why?
Because you don’t have the same amount of control over your vehicle when it is in neutral.

If you need to brake, you will not have the additional help of the transmission downshifting to slow you down, along with the brakes.
And, if you need to accelerate in order to avoid trouble, the extra time needed to put the transmission in gear could make the difference between being able to perform an evasive manuever successfully and not doing it successfully.

Didn’t knew that it was illegal. But again, I only use it when driving down long grades then always shift to drive before coming to a stop. The LX has shif-o-matic. Either way, there is not much traffic up where I live, but I thought the poster was referring to some kind of mechanical problem if you coasted in neutral.