Why does the gen 4 coast better than gen 5?

[calnra]

So this is probably opposite of what most people think about.

I do a good 100 mile a day commute in my 99 Camry with the 5s-FE engine and 4 speed auto three months out of the year. We own another Camry a 2005 with the 2AZ-FE with the 5 speed auto.

I usually opt to take the 99, because when you drive 100 miles a day in SF bay traffic(880) you tend to watch your gas mileage a bit, when a 50 mile one way drive can take over 2 hours. That and the wifezilla likes the 05 because the 05 rides better with much less wear on the shocks

What I noticed is I get about 2-3 mpg better in the 99 than the 05. One thing I attribute to the difference is the ability of the 99 to coast seemingly forever without any throttle. The 05 slows down quickly when you take your foot off the pedal.

I'm hypothesizing it's because of the lower power and torque of the 5S that generate less engine brake. I keep both cars well maintained with religious oil changes, annual checks, properly inflated tires, etc. if anything the higher gearing of the 05 should give more mpg, not less.

Lately it's been running about 30 mpg in rush hour traffic with the 98 and about 27-28 with the 05.

(btw if I keep the 98 at 60mph with no stoppages and a scangauge for reference I get 36-38 mpg on it)

Any thoughts?

[Jimnist]

Heavier OEM flywheel on the 5S? Or maybe brakes are rubbing on the 05?

[Kandasan]

I've noticed this as well, and I have a 1MZ. It seems like our transmissions want to shift straight to the highest gear and stay there, where as the new cars want to stay in gear, or shift down like for instance going down a hill. I think it maybe a way to keep control of speed. I noticed this in my friend's second gen highlander with the I4, when just coasting it seems like the transmission isn't going to the highest gear and just staying in whatever gear it was in when you let go of the throttle. Also, I know not a Toyota, but my friends 07 Civic would shift down when going down the hill and you pressed on the brake, where my Camry would just stay in the highest gear possible. Again I think this is all to control speed.

[redgtxdi]

I can't say I recall with a gen5 but my 5sfe is definitely the coast king. I don't know if the 5sfe does a full fuel shutoff but I believe that also contributes to the feeling, for example, of the brakes while coasting in my venza. Also fuel comes back on as speeds approach 20mph and it feels like it's coasting more like the 5sfe at that point.

I love everything about the 5sfe and gen4 in general. The way it shifts, the sound of the engine, the seating position etc. I don't know why your wife would prefer the ride of the gen5 over the gen4 but to each their own. Maybe the same reason all the gen7's ride like pickup trucks now.

[xpeed]

I beg to differ. My Gen 5.5, ( 2005 ) actually got better mileage than my 5-spd Gen 4. You should have better numbers for your Gen 5.5 over the Gen 4. I got around 36-42mpg on highway and 30-32 mpg city compared to my Gen 4 where I get 35mpg highway and 25 city. Big differences but you are right that the Gen 5s will slow down quicker than the Gen 4 automatic would, but since I have a 5-spd manual, I can't say it since I can make it coast at will or engine brake it.

It's probably due to each person's driving characteristics, but that mainly points towards newer Toyotas having this feature where they use engine braking on downhill coasting to prevent your car from over-speeding and minimizes you overusing your brakes, where if you were going down a mountain side, overusing your brakes will overheat the fluids and lead to possible brake failure. It's more of a new safety feature for new Toyotas starting from 2003 models.

[touringcamry]

One possible explanation is that newer cars sometimes hold a lower gear while older ones will shift up in the same scenario. For example coasting down a hill, some cars will up shift and newer ones tend to hold the gear.

Another explanation, tire inflation pressure and rolling resistance on the tires. (Unless you have the same tires on both vehicles.) Wheels matter too due to rotational inertia.

My 2007 definitely does fuel cut off, but I don't know about vehicles older than that. I think the Gen4 auto did not lock the torque converter in any gear other than 4th so it would not be possible in any gear other than 4th to cut off fuel while coasting. The 2002-6 I don't know if the torque converter locks in any gear other than OD.

What are the cars like as far as their state of repair? Good plugs and filters?

There are probably hundreds of other variables like stuff you've added to exterior, etc.

[bigbird]

IIRC the gearing is the gen4 is slightly taller than the gen5. Toyota's attempt to make the gen 5 a little quicker with the added weight.

[calnra]

The newer car holding a lower gear to control speed sounds plausible.

Originally Posted by touringcamry

What are the cars like as far as their state of repair? Good plugs and filters?

well maintained, with oil change every 3k and annual thorough checkups, plugs, filters, wires, belts, fluids are regularly replaced.

The 05 does great in steady speed driving, but stop-and-go traffic is where the difference shows up.

[calnra]

Originally Posted by bigbird

IIRC the gearing is the gen4 is slightly taller than the gen5. Toyota's attempt to make the gen 5 a little quicker with the added weight.

the additional gear in the 05 actually resulted in a higher OD in my recollection, at 70 the 99 revs at 2500 while the 05 revs at around 2200.

Of course which ever one the wife takes, it magically never gets above 18mpg no matter how much highway driving she does...

[bdy0003]

You are correct sir. I highly doubt the gearing of the tranny has anything to do with gas mileage if you were comparing straight highway for 8-9 hours since it only happens once. My reasons for thinking the Gen 3,4s are more fuel efficient is because of weight and size. Somehow, the older generations are equivalent to today's compact car or darn near close to it. And, the Gen 5 is not as aerodynamic as the 3 or 4.

BTW, my Gen 3.5 gets 2-3mpg more than my two Gen 5, 5.5. However, its not all that fair cause of different commutes. OBTW again, I stay away from 880 cause of the trucks and everyone goes so slow. Try 580.

Originally Posted by calnra

the additional gear in the 05 actually resulted in a higher OD in my recollection, at 70 the 99 revs at 2500 while the 05 revs at around 2200.

[LostSouthernStar]

I have the Gen 4.5 and I can say that when idling only, it doesn't want to coast very far, I have to use a little bit of gas to get it to coast forward when on a flat grade and when engine is warmed up. I'm not sure if there is something wrong or if it is just the way the car was designed, but yes the Gen 4.5 and younger coast further, mainly due to aerodynamics, weight, and the way the engine itself is designed, every engine idles differently and affects the coasting, as some have more engine braking then others.

[touringcamry]

Originally Posted by bdy0003

You are correct sir. I highly doubt the gearing of the tranny has anything to do with gas mileage if you were comparing straight highway for 8-9 hours since it only happens once. My reasons for thinking the Gen 3,4s are more fuel efficient is because of weight and size. Somehow, the older generations are equivalent to today's compact car or darn near close to it. And, the Gen 5 is not as aerodynamic as the 3 or 4.

BTW, my Gen 3.5 gets 2-3mpg more than my two Gen 5, 5.5. However, its not all that fair cause of different commutes. OBTW again, I stay away from 880 cause of the trucks and everyone goes so slow. Try 580.

Despite the bulbous look, the 2002 to 2011 are more aerodynamic than those preceding it because it has a cD of 0.28. The 1997-2001 were 0.30 cD and the 1992-6 were 0.33. You cannot judge that based purely on its appearance.

[bdy0003]

I CLAIM WEIGHT THEN!!!

Seriously though, I don't really enjoy driving the Gen 5 as much as my Gen 3.

Originally Posted by touringcamry

Despite the bulbous look, the 2002 to 2011 are more aerodynamic than those preceding it because it has a cD of 0.28. The 1997-2001 were 0.30 cD and the 1992-6 were 0.33. You cannot judge that based purely on its appearance.

[calnra]

Originally Posted by xpeed

It's probably due to each person's driving characteristics, but that mainly points towards newer Toyotas having this feature where they use engine braking on downhill coasting to prevent your car from over-speeding and minimizes you overusing your brakes, where if you were going down a mountain side, overusing your brakes will overheat the fluids and lead to possible brake failure. It's more of a new safety feature for new Toyotas starting from 2003 models.

In test driving a 2010 Camry I realized the new gear shifter on the 6th gen is just a joystick, no longer the familiar thumb buttons for unlocking and OD select. I know it's due to switching to a computer controlled interface, but it also leads me to think people just didn't understand how much that little OD button can help. Making the car slow down for you kinda tells us how lazy we as a whole have become even with auto transmissions.

[xpeed]

Yeah, not many people know that that little O/D button is for. Maybe that's why Toyota took it out, and not to mention they put in a new transmission starting with the Gen 6 from the 5-spd to 6-spd auto, which takes out the little O/D button, but in lack of the button, Toyota put in something else that will do it automatically for you by reading the incline of the road you're going on. It still doesn't help though when you want it at will.