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

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7
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1answer
2k 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 ...
1
vote
1answer
204 views

97 Bonneville, strange problems accelerating

I'll try to explain this problem as clearly as possible. I have a 97 Bonneville, automatic transmission. When accelerating from idle, sometimes two strange things happen: the car reaches ~20 mph, ...
2
votes
1answer
1k 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
3answers
919 views

1997 Olds 88, trans issue?

A friend of mine pointed me this way due to my current problems; I've been working on this for three weeks and am no closer to diagnosing the issue, so hopefully someone here can point me in the right ...
1
vote
1answer
694 views

Should I change automatic transmission fluid on an older vehicle?

I have a Pontiac Vibe 2004 with an automatic transmission. The mileage now is around 120k miles and I've never changed the transmission fluid. There are no mechanical problems with the vehicle at the ...
3
votes
1answer
692 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 ...
1
vote
1answer
84 views

Cost to alter the transmission system

How expensive would it be to replace a manual transmission system to an automatic?
0
votes
1answer
91 views

Trying to diagnose from this sound when accelerating

I have a '96 Holden Apollo, automatic, that has a point when accelerating where it sounds like its revving up a bit higher and seems like the gears might not be really gripping. Thats my uneducated ...
1
vote
1answer
357 views

Differential Fluid Plug Right Above Catalytic Converter? - '99 Avalon XLS

Recently I was doing some routine maintenance on my 1999 Toyota Avalon XLS and when I was checking the 95k mileage procedures one of the items which caught my eye was replacing the differential fluid. ...
3
votes
5answers
921 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 ...
4
votes
3answers
6k 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 ...
1
vote
1answer
317 views

Automatic trasmission gear lock when accelerating

For awhile now since getting my first car (and only driving Automatic transmissions) I've had plenty of experiences where when making a turn out of a parking lot with my wheels turned a bit too much, ...
3
votes
1answer
971 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. ...
1
vote
1answer
2k views

Best way to diagnose and fix a shifter that sticks in park?

I have a 1997 Caravan [short wheelbase, base model] with a 4-speed automatic transmission. After it sits [off] for a few hours, the shifter will get stuck in park. A little jiggling and a hard pull ...
6
votes
1answer
699 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 ...
3
votes
1answer
282 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 ...
4
votes
2answers
655 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 ...
7
votes
7answers
7k 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. ...
7
votes
1answer
404 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 ...
22
votes
3answers
10k 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 ...
2
votes
1answer
160 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 ...
5
votes
4answers
7k 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 ?
11
votes
4answers
39k 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 ...