Clearly that was a flame then and you're just trying to provoke a reaction. No-one with any basic engineering knowledge would actually believe that.

And no one with real car knowledge would care one way or another if the car had one or not.

 

I use the tach on my automatic transmission car to determine when it has achieved lock-up.
Sometimes when going up a grade it downshifts and drops out of lock

There's a reason the tranny does that. And your probably doing more damage by doing what your doing. When it drops out of lock when going up a grade, it allows the torque converter to do its job, multiply torque. Lock up eliminate this torque multiplication since it's not needed when not going up hill at speed.

Modern automatic transmissions are different from the old days, unless your driving something from ~80's. The don't use bands any more, except some use them for reverse. They are almost all hydraulic applied clutches now, less heat and more holding power.

 

There's a reason the tranny does that. And your probably doing more damage by doing what your doing. When it drops out of lock when going up a grade, it allows the torque converter to do its job, multiply torque. Lock up eliminate this torque multiplication since it's not needed when not going up hill at speed.

I beg to differ. I know what the "tranny" does.
Locking up doesn't hurt anything. It just takes the torque converter out of the loop.
When my transmission shifts down going up a hill it drops out of lock and goes down one gear.
If I back off the throttle slightly, it goes back in lock and the RPM's drop a couple hundred RPM.
But it's now in a lower gear so the engine is not lugging.
So tell me, how does that do any damage??

 

And no one with real car knowledge would care one way or another if the car had one or not.

QED

 

RPM and shaft count is very important for navigation

Don't know much about boats, but that just sounds silly. Have seen some charts and never saw one that said, "proceed north for "x" minutes at 2000RPM and then turn west for "y" minutes at 3000RPM.

 

I beg to differ. I know what the "tranny" does.
Locking up doesn't hurt anything. It just takes the torque converter out of the loop.
When my transmission shifts down going up a hill it drops out of lock and goes down one gear.
If I back off the throttle slightly, it goes back in lock and the RPM's drop a couple hundred RPM.
But it's now in a lower gear so the engine is not lugging.
So tell me, how does that do any damage??

Never said lock up was damaging. The PCM is doing what it's supposed to in that situation, unlocking the convertor so gear changes can be made. What is possibly damaging is reducing the engine RPM. That also reduces the hydraulic pressure in the tranny, right when higher pressure is needed. The reduction of pressure could slow the timing of the kick down, causing the higher gear and lower gear to be engaged together for a longer time than is supposed to happen. And if you know trannies, you know that during shifts, up or down two gear ratios are engaged at the same time in an OEM automatic. To keep shift change jerking at a minimum. Most people give more throttle to get a down shift not less.

 

shortbus, have you ever seen the movie "the hunt for red october"?

Do you remember the scene where they are going thru the underwater canyon and the navigator orders a certain heading at a certain speed and a certain duration?

Well that knot speed requirement is relayed to the engine room. That knot speed is referenced to the shaft speed, which is referenced to the engine rpm.

The rpm is the only thing the engine room can go by. Every propeller rotation will move ship forward a certain distance.

This is how speed and distance can be determined without a smartphone satellite application.

A good navigator can accurately predict the shaft count at the destination port before sailing.

A silly skill that I'm sure is being lost.

 

Never said lock up was damaging. The PCM is doing what it's supposed to in that situation, unlocking the convertor so gear changes can be made. What is possibly damaging is reducing the engine RPM. That also reduces the hydraulic pressure in the tranny, right when higher pressure is needed. The reduction of pressure could slow the timing of the kick down, causing the higher gear and lower gear to be engaged together for a longer time than is supposed to happen. And if you know trannies, you know that during shifts, up or down two gear ratios are engaged at the same time in an OEM automatic. To keep shift change jerking at a minimum. Most people give more throttle to get a down shift not less.

I'm not most people, I'm an engineer.