Questions regarding automatic gearboxes, and associated parts such as torque converters

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25
votes
3answers
14k views

Is there a way to put Prius with dead battery into neutral?

I own a 2010 Prius. It has a dead battery, front facing forward in my garage. I do not have long enough jumper cables. I’ve searched the Internet. Did Toyota really create a car that cannot be put ...
13
votes
2answers
5k views

Why doesn't the engine stall out when you come to a stop with an automatic transmission?

When you come to a stop with a manual transmission you have to push the clutch in or take it out of gear to keep the engine from stalling out. What keeps the engine from stalling in an automatic ...
13
votes
4answers
53k views

What's the point of the D3 gear in an automatic transmission?

My Honda Civic has a D gear and a D3, which apparently prevents it from going into 4th. Why would I want to do this? What is it good for? Does it make my fuel efficiency better or worse? Does it ...
8
votes
1answer
344 views

shifting stops when critically low on gas

I have a 1999 Dodge Dakota. It is a V6, 3.9 Liter, auto transmission. I have a weird problem that no one has been able to answer for me. HOW I CAME TO REALIZE THE PROBLEM: One day I was driving ...
7
votes
1answer
3k views

How does an automatic gearbox know when to change gear

As the title suggests, how does an automatic gearbox know when to change gear, for example, how does the autobox know to shift down when you hit a gradient for example, also how does it know to shift ...
7
votes
1answer
428 views

I'm stupid and added tranny fluid to my coolant tank. What can I expect?

Title pretty much says it all. I'm a computer guy, not a car guy. I saw a bunch of red fluid coming out of my vehcile, assumed it was tranny fluid. Turns out it was antifreeze. This means the bit of ...
7
votes
8answers
10k views

Can coasting in neutral damage an automatic transmission?

When I drove a manual transmission, I got in the habit of shifting to neutral on long, shallow grades to save fuel. Now I'm driving an automatic (specifically, a recent Corolla) and still doing it. ...
6
votes
2answers
259 views

Why doesn't anyone ever repair an automatic transmission?

I am old enough to have had about four transmission failures spaced over about 40 years and at no time did any mechanic ever offer to “fix” it; the only diagnosis has been a complete rebuild. This is ...
6
votes
1answer
872 views

How can I be sure of the reading on my automatic transmission fluid dipstick?

This may seem like a silly question. I've been trying to read the dipstick for my automatic transmission fluid but am having a very difficult time determining the level. The fluid is very light and ...
6
votes
5answers
8k views

Switching from Reverse to Drive - always stop completely?

I've been told by a couple people that it's really bad for a car to be shifted from Reverse to Drive while the car is still moving backwards. Is this true? In my experience: On automatic cars, this ...
5
votes
2answers
1k views

How to put 1997 Toyota 4Runner in neutral with dead battery?

My ’97 Toyota 4Runner with automatic transmission is parked head first in a small garage with a dead battery. I need to put it into neutral to push it out on the driveway so I can jump-start it. (This ...
5
votes
4answers
9k views

Can I use a Dexron III automatic transmission/power steering fluid where a Dexron II is required ?

more generally speaking are 'higher Dexron numbers' also fulfilling the specifications of the lower number fluids ?
5
votes
1answer
693 views

Automatic Transmission or Differential Backlash (Play)

I noticed that my car has what it seems to be significant differential play. I have a 1993 Acura Integra with automatic transmission. What I mean by play is simple: say I jack up only one front wheel ...
4
votes
4answers
9k views

Strong vibrations when idling even after replacing engine mounts (automatic transmission)

I have a '93 Acura Integra with automatic transmission. Ever since I got it some time ago the car has been vibrating a lot when stopped at a light, for example. The vibration is worse when in gear ...
4
votes
2answers
754 views

How hot is “HOT” on a transmission fluid (ATF) dip stick?

I want to add some fluid additive (Lucas) to my transmission, but I don't want to overfill it. The dipstick has add, warm, and hot for measuring. So how hot is the hot level? My temperature gauge ...
4
votes
3answers
9k views

What is ECT Mode for? - Toyota Cars?

I'm not sure if this is a feature on Toyota cars alone, but I currently drive a '99 Avalon XLS and in addition to the D3 mode which I know disables overdrive, right above the radio near the top of ...
4
votes
2answers
760 views

Do I need computer reprogramming when transmission is replaced?

Honda Odyssey 2003: I'm replacing a transmission, and a local mechanic will help me to swap it in my garage. I've been told at a local shop, that in order to install remanufactured transmission ...
4
votes
2answers
222 views

What determines when an automatic transmission shifts?

I'm working on developing an automatic bicycle (mostly microcontroller based) and I'd presume I'd be shifting in a similar way to a car. So my question is, what factors does the transmission take into ...
4
votes
1answer
363 views

Grinding Sound at Specific RPM/Speed

I have a 2011 Ram 1500. For about a month I thought I was hearing a clunk between 2nd and 3rd gear. I finally decided to listen carefully by turning my radio off. I now certainly notice it, but it is ...
4
votes
1answer
459 views

2012 Toyota Tacoma won't shift into Reverse

I've just had my 2012 Tacoma towed to the dealership due to the truck not shifting into reverse correctly. I first noticed a problem when I was driving home and the RPMs would get up to between 3 and ...
4
votes
1answer
235 views

What to do when a mechanic can't reproduce possible transmission problems?

I have limited experience with cars. I bought a 2001 Mazda 626 to commute to and from school a few weeks ago. Today when merging on the freeway I noticed that the engine sounded like it was working ...
4
votes
1answer
2k views

Ford Escape won't shift into gear, O/D light flashing

I've got a 2002 Ford Escape (automatic transmission) that will start fine and reverse without any problems, but when I put it in drive and try to pull forward, it remains in idle. I can hit the gas ...
4
votes
1answer
582 views

Remove transmission cooler lines K1500 '00

What is the trick from removing the cooler lines from the transmission on my 2000 k1500? I know how to disconnect the lines. I just don't know how to reach the clip on the lower connection on the ...
4
votes
2answers
674 views

Saab 9-3 stuttering and cutting out [closed]

I've got a 1999 Saab 9-3 2.0l Automatic (not the turbo). It's been running fine, then a bit more than a month ago it started to stutter when accelerating or decelerating. Only occasionally, but it ...
3
votes
4answers
1k views

Does switching to neutral on an automatic transmission improve braking for immediate stopping?

I've been told that when needing to brake quickly, throwing the gear into neutral on an automatic transmission actually allows for better/quicker braking. I understand how things work pretty well but ...
3
votes
5answers
1k views

Should you change all of your transmission fluid?

I took my Lexus RX 300 to the shop, to change the transmission fluid. While talking to the tech, he said he sucked out half the fluid and left the other old half there. Is this proper? Shouldn't they ...
3
votes
3answers
7k views

Automatic transmission: Is shifting to neutral while approaching stops bad?

This is not with the intention of saving fuel (as I have seen many answers assuming savings in fuel while doing this). But I have this habit of putting the vehicle into neutral before approaching ...
3
votes
1answer
93 views

Is my transmission about to go?

I drive a 16 year old Subaru Legacy automatic which still has its original transmission and has never given me a moment's trouble in 16 years. Today while pulling out of a parking spot, I suddenly ...
3
votes
2answers
2k views

Durability of automatic transmission boxes versus durability of manual transmission boxes? Their lifetimes?

My friend is against cars with automatic transmission because he thinks that they break easily and that their repairing cost a lot. He thinks that it is impossible to maintain an automatic ...
3
votes
1answer
96 views

Better to repair a CVT or replace with a used one?

Our 2003 Honda Civic Hybrid transmission died. Honda gave us an estimate of $4500 to replace the transmission. We took it to a different mechanic who suggested that instead of replacing the whole ...
3
votes
1answer
60 views

Handbrake Engaged for 9-10 km Driving Roughly 80 km/h

Make: Mitsubishi Model: Pajero Intercooler 2800 Handling: Automatic Year: 1992 I forgot to release the handbrake on my car this morning. I didn't realize I forgot to release it until I had driven ...
3
votes
1answer
81 views

AWD truck doesn't shift smoothly. I was advised to not change the transmission fluid

AWD Mercury Mountaineer. 1997 Automatic transmission. 8 cylinder 5.0L 150k miles. fairly good shape. Pretty awesome truck. From 1st to 2nd gear, the transmission shifts with a light clunk. Also, at ...
3
votes
1answer
387 views

Howling sound when accelerating

I have a 2007 Ford Ranger that makes a faint howling sound when I'm accelerating, usually after being idle at a stoplight. I've tried slowly revving in neutral and I didn't hear the same noise. ...
3
votes
1answer
822 views

2006 Audi A4 2.0T, No passing power

I have a 2006 Audi A4 2.0T Turbo Tiptronic Automatic that has no passing power. When I step on the accelerator the car will shift down into a lower gear, rev about 3500 RPMs but will not shift up ...
3
votes
1answer
1k views

2004 Mazda 3 - clank when shifting into reverse

Every morning, or after the car has sat for a while, there is a loud clank from the engine area when I shift it into reverse. Sometimes I hear the same clank when shifting into drive, but not always. ...
3
votes
1answer
291 views

How to fix an electronic transmission that chooses overdrive and torque converter lock

'95 BMW 540i Automatic If I drive for a short (5 min) trip say go in to a store and come out. The engine will start and idle fine, but upon gear selection the car will try to drive through the brakes ...
3
votes
0answers
249 views

Could a fuse be responsible for my VW Jetta not shifting while in drive?

Issue with my VW Jetta (2001) Automatic transmission, gasoline engine My tail lights were out because of a missing fuse. So in the dark I looked to find a good one to replace it with (of the ones ...
3
votes
0answers
145 views

Pulley Difference After Drive Belt Change

I have one worry after yesterday's fairly difficult but successful drive belt change on my Big Boy scooter. The main nut on the fron pulley now goes on much less further than before it came off. I ...
3
votes
0answers
435 views

2004 Chevy Malibu jerks when deceleration is followed by acceleration between 25-40 mph

I recently noticed that when coasting or breaking is followed by acceleration (seems to be only when the car is moving between 25 and 40 mph) that there is a slight jerk. After recreating the problem ...
3
votes
1answer
445 views

Manual ECU with Automatic Car

Have 92 Accord with 1.8 VTEC. The Installed Engine is From 98 Accord. The transmission is the original which came with 92 accord. This transmission is operated by Kick Down cable and does not have any ...
2
votes
6answers
9k views

Use of Neutral Gear in Automatic Transmission

I am new to driving A/T cars and I am trying to understand the use of Neutral(N) gear. Should I shift my gear from D to N when my car comes to a complete halt on a red light or somewhere else? As per ...
2
votes
1answer
168 views

when parked on uphill, it's difficult to engage any other gears on my automatic chevy 2004 impala.

when the car is parked on uphill, and I try to move the gear back on to reverse, it becomes extremely difficult. Like you have to put a little effort into it. Once it gets into gear, it makes a loud ...
2
votes
1answer
546 views

2003 Honda CR-V AWD - intermittently Flashing Drive light

My Wife's 2003 Honda CR-V's Drive light in the cluster occasionally starts flashing. The manual states that this means that the transmission requires service, but it doesn't do it all the time, and ...
2
votes
1answer
115 views

What are MDLA and MDMA?

I'm looking at stuff for my 2001 Honda CR-V on Amazon.com, and it has a filter for transmission type. There are two options for automatic: MDLA and MDMA. I have searched on Google, and found the ...
2
votes
4answers
1k views

Can't move Chrysler 300M gear selector out of park

I got into my car this morning and couldn't move it from park after I started it. I can't change the gear at all. I can move the wheel, though. I've tried to wiggle it but haven't forced it because I ...
2
votes
1answer
78 views

Vehicle squeaking 3-4 times when beginning to drive. Stops after getting some speed

Recently I've noticed that my 2012 Nissan Frontier (Automatic Transmission) is squeaking when I start driving from a complete stop. It will only squeak 3-4 times and will go away once I've gained some ...
2
votes
1answer
3k views

Engine Coolant Temperature sensor goes bad whenever the outside temperature is hot

This is on a 1998 Chevy Cavalier, automatic transaxle, 2.2L. This sensor went bad last July and I replaced it then. When it goes bad, the check engine light comes on and then the temperature gauge ...
2
votes
1answer
2k views

Auto transmission shifting late, staying in low gear

The mother-in-law's 2005 Renault Clio (auto) shifts very late and stays in too low a gear. When decelerating the tranny downshifts early (it really likes the revs). The garages all want a heafty sum ...
2
votes
1answer
46 views

Toyota Hilux Surf 1998 Stuck in Park and speedometer and odometer not working

I just bought a 1998 Hilux Surf. It has an automatic gearbox. When pressing the brake the drive selection should be unlocked, but it does not. I need to use the "red button" to unlock the drive ...
2
votes
2answers
203 views

On a BMW E46 330Ci, is it necessary to pull the handbrake lever when you're in 'P' mode?

My flatmate drives a 2001 BMW E46 330Ci automatic transmission. I sat next to him while he drove us to the supermarket. When we arrived, I noticed that he only put the gear lever into 'P' and switch ...