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Car transmissions - Standard or automatic?
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John McLeod VII Send message Joined: 15 Jul 99 Posts: 24806 Credit: 790,712 RAC: 0 |
I always drive my car via the rev counter (tachometer) it is more accurate for speed than the speedometer. I know that in 5th gear it is 22mph/1000 rpm so I just know that 2000 is 44, 3000 is 66, and 4000 is 88. Also if I want to get my foot down it is useful to know whether the engine is in its max torque or power curve, or whether I need to drop a cog. Many times I see people pull out to overtake, try to accelerate and hardly anything happens, by the time they've taken a lower gear to pull away, there is a car up their backside in the outside lane! Some cars now have an oil level light in addition to an oil pressure light. The oil level light goes on when a quart down (in the US anyway). I found this out by reading my owner's manual. The only warning light I have seen on my car is the low fuel (which comes on with 70 miles or so left in the tank.) BOINC WIKI |
Gordon Lowe Send message Joined: 5 Nov 00 Posts: 12094 Credit: 6,317,865 RAC: 0 |
I do look at the tachometer from time to time but one place where it is very useful is when you are using engine braking on a long down hill grade. Often high gear will not provide sufficient braking so you keep downshifting till you find a gear that will hold. On the motor home this was a real problem because it had an automatic transmission and anything over 2500RPMs could end the life of the engine. The weight resulted in a fine balancing act where you didn't take all day to get down the hill but you didn't damage the drivetrain or overheat the brakes. There was a movie with Lucy and Desi where they were in a motorhome, and for some odd reason, that's what popped in my mind when I read this. ;~} Some cars now have an oil level light in addition to an oil pressure light. The oil level light goes on when a quart down (in the US anyway). I found this out by reading my owner's manual. The only warning light I have seen on my car is the low fuel (which comes on with 70 miles or so left in the tank.) I've done the silly thing of “testing†my fuel low light. Don't try that. :~} In regard to monitoring speed with the tach, maybe I could have used that idea when my old Nissan Sentra's speedometer cable was broken. I got a ticket for speeding, but it was waived after I got the cable fixed. The car's odometer was also controlled by that cable, so it went awhile in virtual agelessness. I always bring my manual transmission car back to neutral when I stop at a stop sign or a red light. Is this what you all do? I keep my foot on the brake, of course. The mind is a weird and mysterious place |
betreger Send message Joined: 29 Jun 99 Posts: 11415 Credit: 29,581,041 RAC: 66 |
If god wanted me to drive an automatic he wouldn't have given me a left foot. |
bill Send message Joined: 27 Apr 12 Posts: 171 Credit: 2,167,701 RAC: 0 |
I started with an austin cambridge many year ago, |
John McLeod VII Send message Joined: 15 Jul 99 Posts: 24806 Credit: 790,712 RAC: 0 |
The only warning light I have seen on my car is the low fuel (which comes on with 70 miles or so left in the tank.) Depends on where you are. On my route to and from work, there are about a half dozen gas stations I can stop at easily. The round trip is a bit over 50 miles. In the south west, I have seen a sign that said last chance for gas for 130 miles... BOINC WIKI |
J. Mileski Send message Joined: 9 Jun 02 Posts: 632 Credit: 172,116,532 RAC: 572 |
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betreger Send message Joined: 29 Jun 99 Posts: 11415 Credit: 29,581,041 RAC: 66 |
In my rig, left for clutch, right for gas and brake That is the "proper" way to drive. |
Jim Martin Send message Joined: 21 Jun 03 Posts: 2481 Credit: 646,848 RAC: 0 |
A brief return to sensors/gages -- When I was ten, my father, one day, asked me if I cared to knock out a dent in the right, front fender. Of course, I readily agreed. He knew that I could do it, having watched him change tires, many times in the past -- and, this would involve jacking up the car ('36 Chevy), removing the tire (w/rim), and then taking the ball-end of a ball-peen hammer, and pounding out the dents, from the inside of the fender. Reverse process, for a completed job. I did all that, and he was quite pleased. The point, here, is -- With low-pressure sensors in the tires, a person is obliged to take the car to a repair shop (usually, the dealership, today), to have even a hub-cap removed. My point -- not to sound technically-elitist -- is, that, perhaps, cars are being designed for the least-technically-inclined. And, folks who understand at least the basics, are being shunted off to the side. Another example -- Hard-copy road maps? Try Barns & Noble; they're not in gas-stations, any more. Why paper maps? Put the picture of the map in your head, and you don't have to take your eyes off the road to look at a GPS device. |
Julie Send message Joined: 28 Oct 09 Posts: 34060 Credit: 18,883,157 RAC: 18 |
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Jim Martin Send message Joined: 21 Jun 03 Posts: 2481 Credit: 646,848 RAC: 0 |
My two oldest kids know how to down-shift. The youngest couldn't care less. Driverless cars, here we come, I guess. A follow-up point, Chris, is ... what will freeing up our minds lead to? People are becoming more and more detached from former knowledge, to be replaced by an environment which is increasingly-isolated from previous reality. A case, in point: It's becoming more difficult to engage people's interest in nature and its problems. They don't have a "feel" for it, any more. Many homes in Lexington, anyway, have lawn-service. The owners of those homes are too busy in the technical world. They don't realize/care about the consequences of having easy-to-maintain lawns, plus a few shrubs and trees. Everyone, over here (it seems, from my perspective, anyway) wants his place to look like Her Majesty's grounds, and maintained, accordingly. Disaster, when multiplied many-fold. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66336 Credit: 55,293,173 RAC: 49 |
Driverless cars, here we come, I guess. Oh yeah, speeding along with no steering wheel, no brake or accelerator pedals at 25mph max, that's the google self driving car, good for the blind really... @ 25mph it's not much to crow for, as it would take ages to get anywhere, I'll keep My driving skills sharp and drive My own car. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31006 Credit: 53,134,872 RAC: 32 |
Driverless cars, here we come, I guess. 25 is full speed and then some in LA rush hour traffic. |
Dena Wiltsie Send message Joined: 19 Apr 01 Posts: 1628 Credit: 24,230,968 RAC: 26 |
It's not quite like that Jim! Back in the early 60's when I first passed my test, cars were so simple that a 10 year old could work on one (and they did!). At that time in the UK there were still some pre war push-rod sidevalve engines about although OHV and OHC were becoming the majority. You opened the bonnet and you could get to everything, plugs, points, carburettor, filters etc. In those days we changed the vegetable based engine oil every 3000 miles, used flushing oil as well, and used different grades for winter and summer, But quite soon, 20W/50 multigrade mineral oils were coming in that lasted 5000 miles. The extended oil changes are the results of tighter engine tolerances and better additive packages in the oil. My mustang 4.6l with 123,000 miles will still run 5000 miles without adding oil and at oil change time, the oil is still clean enough to see through. But, technology moved on, cars became more sophisticated, Fuel injection came in, electronic ignition, engine management chips, diagnostic machines, instrument panels had a plethora of warning lights. You open a bonnet of a modern car these days and you just shake your head and close it again. Plugs last 60,000 miles, good job, ever tried finding one? You could change the old air filters in seconds, these days they are hidden away somewhere in many feet of ducting. Modern multigrade synthetic engine oils last for 20,000 miles or 2 years, with no sludge in the sump. Good job really as that is where front wheel drive cars effectively have the gearbox! I would put the blame for this on the United States. The technology for fuel injection and engine control has been around a long time but it was far to costly to use. Our pollution control regulations where impossible to achieve without far better engine control so when everybody had to use the technology, it's cost was no longer a disadvantage and everybody switched to it. |
Gordon Lowe Send message Joined: 5 Nov 00 Posts: 12094 Credit: 6,317,865 RAC: 0 |
I change my oil every six months, but have resisted using the synthetic stuff. Any thoughts on this? Also, how often do you all change your manual transmission fluid? My 1999 Saturn SC1 has 133,000 miles on it, and I had the fluid changed just a few months ago, and that was my first time. I bought the car in 2008, when it had 108,000 miles on it. The mind is a weird and mysterious place |
Dena Wiltsie Send message Joined: 19 Apr 01 Posts: 1628 Credit: 24,230,968 RAC: 26 |
I change my oil every six months, but have resisted using the synthetic stuff. Any thoughts on this? Check the owners manual for the oil change period on the manual transmission but 100,000 miles sounds about right for manual transmission or rear ends. The real determination on oil changes is how long the additive package holds up. Truck driver don' t change oil by miles because it can take over 4 gallons of oil. They pull oil samples and send them to a lab that runs a check on the additive package. When the additive package starts to break down, it's time for an oil change. Synthetic oils do tend to last longer but without a test kit, I would advise you stick with the factory oil change period. The reason for changing the oil is not because the oil wears out. The reason is because the additive package breaks down or the oil is carrying to much grime. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66336 Credit: 55,293,173 RAC: 49 |
Driverless cars, here we come, I guess. I doubt it would be allowed on a freeway, otherwise a moped could probably go there, I had one that would do 25mph and there were mopeds that did more than 25mph. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Gordon Lowe Send message Joined: 5 Nov 00 Posts: 12094 Credit: 6,317,865 RAC: 0 |
The reason for changing the oil is not because the oil wears out. The reason is because the additive package breaks down or the oil is carrying to much grime. My car's engine oil gets dirty. I drive light miles, but always city stop n' go, never highway. It's amazing to me that the transmission oil doesn't need to be changed as frequently as the engine's. The mind is a weird and mysterious place |
kittyman Send message Joined: 9 Jul 00 Posts: 51478 Credit: 1,018,363,574 RAC: 1,004 |
I change my oil every six months, but have resisted using the synthetic stuff. Any thoughts on this? I run synthetic in my 24yo 1990 Olds Cutlass Ciera. Why? Because it is the best for the motor. Which still has only 60,000 miles on it, and I intend to drive the car until the wheels fall off. Rebuilding the suspension in a couple of weeks. I change engine oil twice a year, spring and fall, not because it really needs it with the low mileage I drive, but I prefer to run 20w50w in the summer and 5w30w in the winter to make cranking a bit easier when it gets down below zero f here. Your statement about the additives in oil being what 'wears out' is largely true. I have not changed the auto transmission fluid, but I did top it off with a bottle of additive restorer. I think it may have been from Lucas. It replenishes the detergents and thingys that keep gum and sludge from building up and the seals from hardening. Another thing I might point out about automatic transmissions...sometimes when they act up, the filter has to be changed. Yes, auto trannys have a fluid filter too. It's inside the pan. I had a couple of old high mileage Buicks years ago that when the weather got cold, would hesitate to go into gear in the morning. That's because the filter was clogged up and the cold, thicker fluid would not flow through it readily. "Time is simply the mechanism that keeps everything from happening all at once." |
Dena Wiltsie Send message Joined: 19 Apr 01 Posts: 1628 Credit: 24,230,968 RAC: 26 |
The reason for changing the oil is not because the oil wears out. The reason is because the additive package breaks down or the oil is carrying to much grime. Two thing break down motor oil. One is the engine runs at higher temperatures and there is blow by from the rings. Transmissions have oil coolers that allow the oil to reach the optimum temperature and then tend to hold that temperature. I saw a table once from GM and it indicated oil at room temperature would last forever but at the temperature increased, it's life was shorter. That is also the reason why oil coolers have been added to engines. Automatic transmission can have a shorter oil change period if they are used to pull heavy loads because the temperature may rise above the normal operating temperature. This will result in a burnt smell. |
kittyman Send message Joined: 9 Jul 00 Posts: 51478 Credit: 1,018,363,574 RAC: 1,004 |
The reason for changing the oil is not because the oil wears out. The reason is because the additive package breaks down or the oil is carrying to much grime. If the oil truly has a burnt smell, it usually means you are burning up the clutches with slippage. Not usually from the fluid itself. "Time is simply the mechanism that keeps everything from happening all at once." |
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