Hot answers tagged automatic-transmission
19
The reason that an automatic doesn't stall out while "in gear" and at a stop, while a manual transmission does, is that automatic transmissions use a hydraulic torque converter to connect the engine to the transmission, while manual transmissions use a friction clutch. These two systems do a similar job in a very different way.
A torque converter uses fluid ...
17
According to 2010 Prius Emergency Response Guide (page 10):
Being electronic, the gearshift selector and the park systems depend on the low voltage 12 Volt auxiliary battery for power. If the 12 Volt auxiliary battery is discharged or disconnected, the vehicle cannot be started and cannot be shifted out of park.
The auxiliary battery is located in the ...
14
It is important to note that revving the engine on an automatic transmission car while holding the car stationary with the brakes causes premature transmission wear and early failure. This action causes the fluid to overheat. It also damages the torque converter and driveshaft or cv joints.
If you look at advertisements for performance torque converters ...
12
In addition to what Patrick said, D3, or whatever else it's called in various makes and models, is also useful for those times when you're climbing a hill and the transmission keeps shifting back and forth between gears.
There may also be times, such as when driving on very slippery surfaces, when a gear shift could cause the car to lose traction. In such a ...
12
This is analagous to down shifting in a manual. This is a lower gear for the transmission which means the engine revolves at a higher rate producing more back pressure at the same speed as a higher gear.
When going down a hill, if you downshift that will reduce the demands on the braking system, due to the back pressure. You will often see truck drivers ...
9
If you haven't run the car yet then just drain out the reservoir. If you have run the car then some of the fluid might have started to circulate through the cooling system. If so, flush your coolant.
A small amount should not affect the car's ability to stay cool. So this is not that critical, but you definitely don't want to let your engine overheat.
8
Here are the exact instructions from the owner’s manual:
Operations are the same except the item number three:
If you cannot shift the selector lever out of “P” position to other positions even though the brake pedal is depressed, use the shift lock override button as follows:
Turn the ignition key to “LOCK” position. Make sure the parking ...
7
You can add more fluid, but it's best to do it slowly. Your transmission has a lot of gears and tunnels and holes for transmission fluid to go, and it's important to get the fluid down in there in order to get an accurate reading on the dipstick.
After adding fluid, take another ride out on the freeway for a few minutes and make sure you go through all of ...
6
I don't think it will make a difference on gas mileage either way. Anytime the engine is running the front pump on the transmission is being turned by the torque converter and is lubricating the transmission which is also circulating fluid through the transmission cooler.
I don't see how it could cause premature failure of the transmission. Technically you ...
6
Think of it this way.
If you need to brake so incredibly hard that you're worried the automatic transmission is getting in the way, you're better off worrying about things besides whether or not you're in neutral. You're probably about to crash or lose control, so train yourself to concentrate on steering, or making sure you're arms are out of the way of ...
5
To put it bluntly, they had to implement a fuzzy logic analog computer based on hydraulics rather than a digital computer based on binary states:
As usual, How Stuff Works has a reasonable introduction to the basic concepts with enough vocabulary to kick off more detailed research if you're really interested. That link will take you directly to the ...
5
Short answer for Transmissions, Yes.
DEXRON®-VI licensed fluids are fully
backward compatible and can be used in
all applications covered by earlier GM
ATF specifications."
"DEXRON®-VI replaces DEXRON®-III and
DEXRON®-III-H in all applications
except power steering and manual
transmissions
All DEXRON-III licenses expired at the
...
5
A lot of newer cars are smart about shifting (they have electronic solenoids to control the hydraulics). I can put my 2001 Nissan Pathfinder in reverse at 50 MPH, and it's smart enough to not engage, it goes into neutral. However, at speeds below its cutoff point (I've done it at about 15 MPH and regretted it), you can put a lot of stress on the drivetrain ...
5
For general driving, you can leave the car in drive. It doesn't damage the transmission leaving it in drive while stationary at the lights - although you don't want to be doing silly things like revving the engine while holding the brakes on.
In an automatic car, you don't really use neutral. It is a step on the way to selecting Park, which means that the ...
4
In most cars it's a major operation and quite expensive. There's usually body and mount modifications that need to be made. You'll need the new trans and all the controls. Some cars have a different ECU and wiring harness for each transmission. Possibly vacuum system modifications. Sometimes it even requires changing out drive/halfshafts, etc. What ...
4
Follow the vehicle's designated maintenance schedule. If it says you should change the automatic transmission fluid at a mileage near or below 120k, then change it. If not, then don't.
The manual for your 2004 Pontiac Vibe states:
Change automatic transaxle fluid every 60,000 miles (100 000 km) if
the vehicle is mainly driven under one or more of ...
4
If "injector cleaning" products helped but only lasted for one tank, I would try spraying Seafoam directly in at the throttle plate rather than putting an additive in your fuel. This should be a lot more effective at cleaning the injectors.
If that doesn't help, my best guess would be that the vibration is from unequal power from one or more of the ...
3
Being in Neutral or Drive should have negligible to no effect on the distance the vehicle travels when the accelerator is not pressed because the torque converter disengages the engine below predetermined RPM levels.
However, if you somehow were to push just a little too hard and sent the transmission into Reverse instead of stopping in Neutral, you would ...
3
Make sure in the future that where you store your smart key is more then 15 ft. away from the car. If it is within 15 ft. it will drain the battery or deactivate the smart key fuction if the car is left for longer then a week. Under the steering wheel there are 2 red buttons. The left one is for the smart key system right one for tire presure monitoring.
3
That sounds pretty strange to me. I'll admit I don't know a lot about automatic transmissions, but with a manual gearbox I would always drain all the fluid when changing it. As gearboxes wear, small metal filings accumulate, and one of the reasons for changing the oil is to get rid of these filings which, if left to build up unchecked, cause even more wear. ...
3
I am looking @ Page 96 of 1999 Toyota Avalon Owner's Manual. This page shows Dash buttons with labels & some nore. This is what written on that page for ECT.
"PWR" (Power) mode for powerful acceleration
ECT
PWR "PWR" mode indicator light on the instrument panel shows the driving pattern selector button is in "PWR" mode.
3
In the automatics I've been in where people do that, it's a rather dramatic bang/clunk if shifted from Reverse to Drive while still rolling backwards. I hate riding with people that do that, makes me cringe everytime. I hear newer cars are smarter about it, but it still sounds like a bad idea. I hate to risk my transmission on a sensor that might fail ...
3
This car will be able to go up and down reasonably steep hills, but it is not a powerful car, and it is definitely not an off road car.
650cc and 800cc engines are considered pretty small, but on hill climb vehicles the gearing can give you a lot of torque which will help you climb steep slopes. This car has gearing set up for city driving, so it isn't ...
3
The letters are standard:
Park
Reverse
Neutral
Drive
Sport (or possibly Snow - thanks @Brian)
Braking (usually for going down hills)
None of these have anything to do with 4WD or 2WD selection. If your Daihatsu is the 4WD version, it is permanently 4WD - there is no selector on that spec of car. It was a specific Japanese edition.
You have stated ...
3
This sounds like utter nonsense to me. Try this experiment. Get up to a set speed (e.g. 60 mph) and then let your foot off the gas pedal and time how long it takes you to get down to a low speed (e.g. 20 mph) "coasting" in gear. Now, repeat the experiment putting the automatic transmission in neutral at the same time you take your foot off the gas, so that ...
3
The main purpose of neutral on an automatic is for towing or pushing the car. Obviously you can't push it with the transmission in park, and if you tow it with the transmission in gear or in park and the drive wheels are in contact with the ground, you'll ruin your transmission or your tires or both. I'm sure there are some other uses too, but they're ...
3
putting brakes on while waiting on a red light while your gear is in D
can damage the braking system?
In general, no, you're fine.
I think you've conflated several issues that can lead to issues (if not actual problems):
If you were sitting at a light in drive (D) with your left foot on the brakes hard and your right foot flooring the ...
3
This is not uncommon on automatic trans equipped vehicles. Since you didn't state how fast the car in moving it is hard to say if yours is normal. A slight creep forward is normal (5KMH) moving at anything faster is a problem. If it is moving faster than that the idle may be set slightly high which would cause the car to move while in drive.
2
What you are describing sounds like activation of the automatic's kickdown switch. Which is just that, a switch that forces the engine to downshift to provide more immediate acceleration. This is normal, and is usually a physical switch attached to the end of the gas pedal's travel path. It is activated when, say, 90% or more throttle depressed. Newer cars ...
2
That rev range does sound high. It's sounds like the transmission is trying to shift to overdrive (the highest drive gear) but isn't succeeding (scary jerk but no change in speed).
Some internet research indicates that the CD4E transmission in the automatic 626s from that era could have potential problems. However, reading further, I begin to wonder if ...
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