• HiddenLychee@lemmy.world
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    6 months ago

    What do you find people want to tow? I’m often at a loss when people bring this up because I’ve never once had a moment in my life where I was disappointed by the lack of towing capacity of my small car

    • barsoap@lemm.ee
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      6 months ago

      Note that Americans basically all drive automatic transmissions, those have a thing called a torque converter. Unless that part is actively cooled it’s going to overheat when asked to do high-torque stuff over prolonged durations and as that active cooling needs space and weight it generally only comes with truck-sized vehicles.

      In short: The reason Americans don’t haul caravans and horses and boats with cars is because they can’t drive stick.

      • dual_sport_dork 🐧🗡️@lemmy.world
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        6 months ago

        ?

        Every automatic transmission car sold since the 1970’s and probably earlier has had a transmission cooler, right there alongside or in front of the radiator.

        • interdimensionalmeme@lemmy.ml
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          6 months ago

          Also all of them have locking torque converters so there is no energy loss at constant speed. Also also, unless going upward at an incline. Most of the power requirements come from aerodynamic drag, not rolling friction of the trailer.

          • barsoap@lemm.ee
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            6 months ago

            You can’t lock the converter when accelerating because that’s not a constant speed you’ll stall the motor under the torque load, and to accelerate you need to overcome momentum. Neither drag nor rolling friction are anywhere close to high torque.

            And I have no idea what the previous poster meant with a transmission cooler, I guess it’s a different thing because a torque converter very much is not a transmission, if you want to compare it to anything then to a clutch. In any case I’ve got that explanation from an actual American actual car mechanic and random lemmings aren’t going to change my mind especially while making no mechanical sense.

            • dual_sport_dork 🐧🗡️@lemmy.world
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              6 months ago

              Wow. The remaining 7,950,999,999 people on this planet now have something to be thankful for, because none of them are as wrong as you.

              You clearly did not actually understand what your mechanic told you.

              A transmission cooler is exactly what it sounds like. It is built exactly like a radiator and works the same way. It is mounted in front of or next to the radiator for the engine. On a lot of newer cars it is actually part of the main radiator. Transmission fluid flows through it and excess heat is dumped into the air. On many vehicles it’s also served by the radiator fan, i.e. for situations where the vehicle is not getting airflow because it’s not moving.

              The torque converter is part of your automatic transmission literally operates by moving the transmission fluid. There is no separation between the transmission fluid used in the torque converter and the rest of the transmission where the hydraulic valves use it to actuate the clutch bands, etc. to shift gears. The same bath of transmission fluid is circulated through the torque converter, the rest of the transmission, and the transmission cooler.

              This is not a truck thing. Even my dinkum Saturn SL I had when I was a teenager that was so pathetic it was literally made of plastic and did not crack 100 horsepower had a transmission cooler – as designed from the factory. The vast majority of passenger vehicles made in the last half century or more with automatic transmissions have transmission coolers built in. It has nothing to do with towing, either.

              Your torque converter absolutely can be locked under acceleration and in fact, nearly all vehicles equipped with a locking torque converter do so as part of their normal shifting pattern when moving up through their gears. This is observable from the driver’s seat if you know what’s happening. The locking and unlocking of the torque converter feels like an “extra gear” in between the gears. Some Japanese cars from the 80’s have a “TC Locked” light on a dash that illuminates when the converter is locked and you can watch this happen in real time. The usual pattern is 1st gear, shift to 2nd gear, lock converter, unlock converter and shift to 3rd, lock converter, unlock converter and shift to 4th, etc. A traditional automatic transmission only has 4 gear ratios, but it will feel like it has seven. Guess why.

              Think about it real hard for a minute. A locked torque converter is the same, mechanically, as a fully engaged clutch. If you could not lock the torque converter during acceleration, by the same logic you would not be able to fully release the clutch pedal during acceleration on a manual transmission car, either. It is glaringly obvious that this is not the case.

              I am not a “random lemming.” I have four decades of actual real world mechanical experience and have disassembled and rebuilt more transmissions, engines, and vehicles in general than you have probably sat in throughout your entire life.

              • barsoap@lemm.ee
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                6 months ago

                A locked torque converter is the same, mechanically, as a fully engaged clutch.

                Which stalls the motor under high torque load.

                • dual_sport_dork 🐧🗡️@lemmy.world
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                  6 months ago

                  Tell us you didn’t read what I just wrote without telling us you didn’t read it.

                  The engine will only stall under load if it is at so low of an RPM that it is generating insufficient torque to overcome the inertia. Which if you are moving and in the correct gear for your speed is never.

                  Which is why your transmission has more than one gear.

                  Remember back 30 seconds ago when I told you to think? Actually try it this time. Or maybe plug some of your bullshit into Google first before continuing to make a fool of yourself in front of everybody.

                  • barsoap@lemm.ee
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                    6 months ago

                    Which if you are moving and in the correct gear for your speed is never.

                    In stop and go traffic it’s practically always. The car needs to be able to handle that, it can’t be rated higher than that situation.