Why drive a manual?


#141

hmmmmm… the analogy seems off – if you mean a lit match, it is the flame that lights the fuse, and gravity’s role in the sun’s fusion reaction is not like a flame (and gravity is not like the fuse either)

OTOH, gravity is the force that pushes nuclei together (Newtonian physics) to cause fusion and energy release (Einsteinian physics)


#142

I don’t want to tell you guys to take it outside because I don’t have to listen, but maybe just talk a little lower. :grin:

I suppose at least with a manual, I could nurse it home. Not always the case with an automatic, but still the only manual I have is the lawn mower and I refuse to get the new automatic undependable transmissions.


#143

Another factor may or may not be the fact that a manual has to close and then open the throttle during every shift and also the engine on a manual shift car may have a heavier flywheel, which has to be accelerated along with the car as the engine revs increase.
There are however manuals that can do clutchless shifts at full throttle, used in pro-stock drag racing and also Formula 1 cars.


#144

Closing and opening the throttle on shifts doesn’t engage an accelerator pump anymore since engines are fuel injected. So no extra fuel squirt.

The flywheel isn’t heavier than a flex-plate and torque convertor.

F1 cars have throttle by wire so they don’t actually do full throttle upshifts per se. The dual-clutch types can be shifted with almost seamless power delivery with electronic control of the shift, clutches and throttle. All that is managed by the ECU. NASCAR and most road racing transmissions are clutchless but require a lift or “electronic lift” but can be bang-shifted if you are on good terms with your trans builder.

Drag cars with Lenco clutchless planetary transmissions want the driveline shock of shifting as a boost. Those gearboxes are nearly bulletproof.


#145

What are the unreliable automatic transmissions on the lawn mowers? The hydrostatic transmissions? Those do give trouble sometimes, I think. But I have a 12 year old zero turn with dual hydrostat transmissions and will never go back. Of course, I’ve got a pretty big yard and don’t particularly like mowing. The zero turn (and the ability to increase or decrease speed on the fly) lets me get done with mowing and move on to something else. Cuts the mowing time in half vs. the old style mower I had previously that only had a 2” smaller deck.


#146

The Tuff Torque K46 model hydrostatic transmission are what are on most mowers and are very light duty unless the fluid is changed each year. Problem is they don’t put drain plugs in them so you have to pull it first. Plus you can’t pull anything with them like trailers, sweepers, aereators, etc. or up and down hills. Not until you get to the more pro models with the K66 transmission are they any good. Been an on-going problem so now they are starting to use a plastic CV trans in some but still not the good ole standard variable speed transmission as in the past. If you want a twin cylinder, 42", with a standard transmission, you can’t get it. Either take a hydro or a smaller engine but you can’t get both anymore.

You’ve probably got a couple more substantial hydros or you just mow flat ground and don’t pull anything with them.

That’s my rant for the day and why I’m keeping what I’ve got.


#147

No problem, wasn’t questioning your decision. I’m not sure what type my mower has. It’s a Cub Cadet, but just the variety sold by Lowe’s. I’m pretty sure the transmissions on mine are made by HydroGear, and they do have an aluminum housing. But that’s about all I know about them.

I thought I had a problem a few years ago because one transmission would stop pulling when it got hot, but it turned out to just be the drive belt needed replacing, I think. Before I replaced the belt I did change the oil in the transmissions. I tried to siphon it out, started to disassemble and pull the transmissions, then just said the heck with it, picked up the front of the mower and stood it up. Probably didn’t get all the oil out, but I was tired of screwing around with it. Haven’t had an issue since, so I assume it was the belt. It is kinda dumb that they don’t put a drain plug in them.

I do mow a pretty big hill. Not in my yard, but I mowed my older neighbor’s 2 acres for a couple of years when he had surgery. My yard is a pretty flat 3 acres. I don’t pull anything with it. Never really have pulled anything with a lawn mower.

I wasn’t trying to convince you to buy one. But mine’s been ok. Belts, blades, bearings, and a couple of switches needing replaced over 12 years isn’t too bad, I guess.


#148

I don’t fully open and close the throttle when shifting. I attempt to approximately match RPMs to the shift. Lower for upshifts and higher for downshifts. I had no idea NASCAR race cars now have no clutch. Shifting to neutral when coming to a stop would work. Do they just hit the gas and slam the transmission into first to go?


#149

I think they still have clutches, but with dog box transmissions you can shift without disengaging the clutch.
Nearly all motorcycles use dog box transmissions, no synchronizers in them. You can shift them clutchlessly. Just hold a light but steady pressure on the shift lever, the torque of the engine locks the transmission in the gear it is in, as soon as you roll off the throttle, the transmission will shift to the next gear.

The Liberty transmissions used in NHRA pro stock racing are dog boxes with a difference, the driving side of the dog clutches are undercut so the torque holds them in engagement but the coast side of the dogs are ramped so they kick the dog out of engagement during coast. If you lift your foot off the gas, they will kick the engagement dogs out of engagement.
When doing full throttle shifts, the next highest gear is engaged and the transmission is briefly in two gears at once, the lower gear then kicks itself out of engagement due to the dogs being ramped on the coast side of the dogs. Sort of like the starting crank on old hand cranked tractors.


#150

The rep at tuff-torq said that every manufacturer was given the option of a drain plug for an extra 50 cents and they all turned it down. 50 cents is 50 cents I guess in the lawn mower competition. Maybe the belt but I suspect it was the fluid change. When you get them all apart, you can drill in a drain plug. I think they even have a kit for it, then depending on who you ask, they poo poo the fluid changes. Kinda like lifetime car transmission fluid.


#151

Allow me to toss another wrench in this mess. My Kia Forte SX 6spd M/T has a 2 speed differential. Final drive is 4.10 in reverse 1st and second. Final drive is 3.10 in 3rd thru 6th. I don’t know how the magic works and really have no desire to know. The transition is automatic and seamless. I looked up the transmission ratios once. I recall 4th was close to direct. 5th and 6th are overdrive. At 60mph (accurate speedometer) in 6th engine is turning 1900rpm.


#152

So my 03 needed new trans lines this week, $550, sure a manual no trans lines but on we go.


#153

They have them, they just use them only on pit stops, not to shift as @B.L.E posted.


#154

I wanted a new 2018 Nissan Versa but the common CVT is prone to failure. Nissan has extended the warranty on the CVT but I keep my cars for 20+ years, and the warranty doesn’t last that long. Took a little doing but I found and bought one with a manual. Since I live in a rural area and don’t have to drive in the city, a manual is just fine. In my 50 years of driving I’ve always had manual transmissions with the exception of one 68 Oldsmobile that I owned for less than a year. I suspect manual transmissions will soon be a relic of the past, especially when all new cars are self driving electric.


#155

There must be a way to do that,

My dad had to walk 10 miles uphill both ways between home and school in 6 feet of snow when he was growing up.

If there’s uphill both ways, there must me downhill both ways. :grinning:


#156

That’s not true at all. My 98 5-speed manual on the pathfinder got the same gas mileage as the 4-speed automatic with same engine.


#157

How about comparing apple to apple. Find a manual and a conventional torque converter automatic with the same number of gears and ratio in each gear. And make sure they have the same engine and installed in the same car. I’d bet that the manual would have less parasitic loss


#158

Yes, the manual has less loss but the automatic still gets better mpg’s. I’ve already addressed that in an earlier post and gave an example. Two actually, V6 and V8 Mustangs from 2013.


#159

You’re the one who made the blanket statement that manuals are more efficient…now you want to narrow the parameters.

Automatics (with same number of gears as a manual) EPA ratings are as good or BETTER then manuals. Been that way for a few decades now. Computer controlled shifting is probably the main reason.


#160

Of course I’m narrowing the parameter. That’s because they don’t build passenger cat manual transmissions to utilize the engine’s power efficient.

If the torque converter automatic gets better mileage than a manual, then why aren’t semi trucks hauling produce with them? Their version of automatics are generally manual transmissions with robotic shifting and clutch.