[Partner]

I recently drove my daughters 2010 GLS I4 over mildly hilly interstate. Every time it started up the hill, you could feel it downshift and not too gently either. I have driven the same road many times in my 2007 GLS I4 and have never noticed it downshifting (even if it was a gentle shift and didn't feel it, I would notice the RPMs rise.) Now I know that the 2010 has a five speed A/T and my 2007 has a four speed and a different differential ratio so that the 2010 final drive ratio is a little higher (to squeeze out a little better gas mileage). It would seem that this constant shifting back and forth would hurt gas mileage.
I finally slid the gear lever over into manual mode and that stopped all the down/up shifting. Only on a couple of steep hills did the speed drop noticeably by 5-6 MPH. Maybe 1-2 MPH on most others.
I have not noticed any other odd performance by the transmission, it feels very good.
Anyone else noticed the same occurrence or have a comment on the subject?

 

[v33sonata]

I4's suck, Auto tranny's suck. So that means the combo of the 2 are not going to be much better.

 

[mamamia]

QUOTE (v33sonata @ Jul 18 2010, 06:33 PM) index.php?act=findpost&pid=342760

I4's suck, Auto tranny's suck. So that means the combo of the 2 are not going to be much better.

That was indeed a very constructive, helpful, useful, and productive response, v33.

 

[afob3]

Haven't noticed or been bothered by it.

Back in 07 when child number two was on the way we considered trading out of my Elantra. At the time the Optima had the 2.4l + 5 speed auto combo while the Sonata still had the 4 speed. I noticed the Optima felt quicker from a stop light with the extra gear. The Sonata felt like it was 'lugging' in around town driving and took an extra kick of the pedal to gear down.

 

[mamamia]

QUOTE (afob3 @ Jul 18 2010, 07:49 PM) index.php?act=findpost&pid=342771

Haven't noticed or been bothered by it.

Back in 07 when child number two was on the way we considered trading out of my Elantra. At the time the Optima had the 2.4l + 5 speed auto combo while the Sonata still had the 4 speed. I noticed the Optima felt quicker from a stop light with the extra gear. The Sonata felt like it was 'lugging' in around town driving and took an extra kick of the pedal to gear down.

Yes, I had a similar experience couple years ago when a friend came to town and rented the Optima. I took a short test drive and my impression was also the same, as if the Optima was quicker, lighter to start.... Not sure I understand how, compared to my 4 speed the 5 speed auto would cause it to behave that way, though.

 

[v33sonata]

QUOTE (mamamia @ Jul 18 2010, 05:13 PM) index.php?act=findpost&pid=342764

That was indeed a very constructive, helpful, useful, and productive response, v33.

oops... Sorry my wisdom did not live up to your standards. LOL.

 

[eddietel]

I owned an 85 Toyota Cressida that had the same "habit" of downshifting on slight hills and then holding in the lower gear until it sensed we were on a level grade. I overrode the tranny and manually stopped it from downshifting. After a longer trip, I discussed this with my brother (a Toyota Technician ) and he said to let the car run the way it was engineered. I would get better milage and performance that way. He was right! I got improved highway milage, and the car zipped up and down hills. My 4 speed Sonata I4 first drops the lockup torque converter, then shifts down on hills. It never comes close to the red line on the tach, and averages 40 MPG (CDN Gallons so minus 20% for the US gal).

IMHO I would suggest that 25 years later the engineering is much better, and I would let the car run the way it was designed. You'll get better performance.

 

[downhiller88]

QUOTE (v33sonata @ Jul 18 2010, 06:33 PM) index.php?act=findpost&pid=342760

I4's suck, Auto tranny's suck. So that means the combo of the 2 are not going to be much better.

 

[hitchell]

I am a new owner of a 2010 Sonata 2.4 with automatic and I have noticed the same thing and it is very annoying. I have started moving the paddle shifter over to the manual position and the indicator shows that it stays in 5th gear and there is no more down shifting on slight grades. If the grade is enough, the RPM will increase slightly and the speed stays the same when cruise is on, so I would assume that in manual mode the torque converter does not lock up. I believe it would help the mileage and it is much less annoying. On a trip using this approach at 75 to 80 MPH with A/C on I get better than 30 MPG. I would be interested in anyone else's observations and whether anyone knows if the torque converter lockup is disengaged in manual shift position.

 

[ActionMan]

I use the shiftronic mode only on ascents/descents that cause the AT to continually hunt for the proper gear, which is pretty much any mountain pass in Colorado. 3rd gear seems to provide the best power/RPM ratio on ascents as well as braking on descents, I rarely have to touch the brake on descents. For everything else, including slight inclines, I let the AT do its job. While the downshifting can sometimes be on the excessive side depending on the incline, I put up with it due to the increased MPG I get letting the computer shift. I would guess that this is due to the torque converter locking-up in 5th gear. My last big trip from Denver -> Pagosa Springs -> Taos, NM -> Denver (1100 miles) I got an average of 33 MPG. Trips along the front range (75-85 MPH) get around 35MPG, trips up into the mountains (65-75 MPH) get between 32-34 MPG. I doubt I would get those numbers if it was in shiftronic mode a majority of the time. AC in this car seems to draw very little from the engine and I have not noticed more than a 1 MPG variation when it is on.

 

[sbr711]

QUOTE (hitchell @ Aug 15 2010, 10:15 AM) index.php?act=findpost&pid=349476

I am a new owner of a 2010 Sonata 2.4 with automatic and I have noticed the same thing and it is very annoying. I have started moving the paddle shifter over to the manual position and the indicator shows that it stays in 5th gear and there is no more down shifting on slight grades. If the grade is enough, the RPM will increase slightly and the speed stays the same when cruise is on, so I would assume that in manual mode the torque converter does not lock up. I believe it would help the mileage and it is much less annoying. On a trip using this approach at 75 to 80 MPH with A/C on I get better than 30 MPG. I would be interested in anyone else's observations and whether anyone knows if the torque converter lockup is disengaged in manual shift position.

Recall for 2.4 automatic shift program and engine program set, remind them to restet A/T adaptive after doing programs.. :whistling:

 

[downhiller88]

the 4 speed in my 2.4 sonata feels like its from 40 years ago, its sooo slow and soo lazy and its feels like its eating away all the power cuz the gear ratio is just so terrible.. idn why hyundai even put a 4 speed in the sonata for the north american market.. (2006-2008 2.4 sonata in korea came with 5speed automatic) didnt know why they didnt just use that..

 

[TJ8522]

QUOTE (ActionMan @ Aug 15 2010, 09:35 AM) index.php?act=findpost&pid=349480

I use the shiftronic mode only on ascents/descents that cause the AT to continually hunt for the proper gear, which is pretty much any mountain pass in Colorado. 3rd gear seems to provide the best power/RPM ratio on ascents as well as braking on descents, I rarely have to touch the brake on decents. For everything else, including slight inclines, I let the AT do its job. While the downshifting can sometimes be on the excessive side depending on the incline, I put up with it due to the increased MPG I get letting the computer shift. I would guess that this is due to the torque converter locking-up in 5th gear. My last big trip from Denver -> Pagosa Springs -> Taos, NM -> Denver (1100 miles) I got an average of 33 MPG. Trips along the front range (75-85 MPH) get around 35MPG, trips up into the mountains (65-75 MPH) get between 32-34 MPG. I doubt I would get those numbers if it was in shiftronic mode a majority of the time. AC in this car seems to draw very little from the engine and I have not noticed more than a 1 MPG variation when it is on.

On slight grades on the highway, mine will downshift to 4th running 55-65MPH and hold that until I have been on level ground for a tad. I usually let the trans do the shifting. It just depends on what you are used to. I have driven a friend's Mazda with a 3.7 v6 and a 6speed trans that never found the proper gear on a hilly road running less than highway speed, and I have personally owned a 1991 Mercury Topaz GS with a 3speed that NEVER downshifted if you were going more than 45MPH because it was already past 2500RPM and the line on it was 5500RPM. 80MPH in that car was fun, and loud.

The Torque Converter seems to unlock only moments before a downshift is made, but sometimes will and relock if I am only going up a very slight hill, but to sum it all up, I feel that this car does seem to keep the transmission pretty busy on the back roads. I have only owned it for a month and had a Trailblazer with a 4.2 I6 and 4speed that rarely needed to downsift (65MPH was about 1800RPM)