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Automatic Transmission Mannerisms

19859 Views 20 Replies 11 Participants Last post by  hikingmike, 
hikingmike
I have a new xB with just over 1K miles on it and I'm sure everything is working great but I thought the behavior was interesting and I'm not accustomed to it so I thought I'd post my observations here and see what your guys' responses were. Let me say this my first 4 cylinder and first non-Ford or Pontiac.

No coasting:
It slows down after I let off the gas (I'm sure this is not news to you guys). It doesn't coast. And I'm not talking about just air drag. This seems to be something that would hurt MPG, would it not? Is it downshifting pretty quickly after letting off or what exactly is it doing?

My wife's MINI (with CVT) does this as well except it is definitely more pronounced. It will slow down moderately after you let off the gas, and then at a certain point it will feel like you are braking, and then eventually it will release suddenly and you'll coast freely until you stop the car. If you're not used to it, you'll pull up to a parking spot or you'll pull up to a traffic light and basically stop way early. It's a bit odd having that happen and you have to hit the gas a little more to make it all the way into your parking spot. I'm accustomed to it now though. Just go in hard, lol.

My previous cars would coast freely for a long time and gain speed on downhills moreso than this car does.

Now why is this? Is this done to save brakes? It could very well save you in the long run with brakes. Is this generally how automatic cars behave now?

Up and down revs when lightly pressing gas to maintain speed:
Now this one is a little more concerning as it's a strange behavior. Since coasting is different, I will sometimes depress the gas very lightly to maintain speed. Sometimes I will notice the RPMs start to go up and down like the transmission is confused and I feel it too. There is a particular downhill I took today where I'm going 45 and it's pretty obvious. Maybe I'll try it again and make a video. It doesn't seem healthy. Is it shifting on me or what?

Untimely downshifts:
This car downshifts a lot more than my previous cars. Ok it's a 4 cylinder, no big deal. I don't yet have the shift points ingrained in my being. I knew exactly when my previous cars would shift and I drove with them. I notice when I'm taking a turn oftentimes as I accelerate out of the turn it has to downshift to get me going. That's fine but it would have been great if it downshifted earlier when I was braking or coasting (or not downshift at all) because it causes a noticeable delay in acceleration right when you're gassing it. I'm not racing here either. The same happens if I have been coasting up to a traffic light and then when I can go I start hitting the gas again lightly, it downshifts causing a little pause. I would prefer it keep it in the same gear and then downshift if needed by me pressing a little harder.

2nd gear, sluggish, then zoom:
Again 4 cylinder ok, I have no problem dealing with it and the car is really fun to drive. If I hit the gas harder after the shift to 2nd, it won't respond much until it gets to 3500RPM. At that point it feels like an imaginary rope starts pulling the car on faster. Woo, fun. My other cars didn't have any surges like that.

Now I notice that the first gear is pretty short. What I mean is the xB can jump nicely in 1st or if you're not gassing much it skips to 2nd pretty quickly so perhaps they geared it for power at lower end there. If you are gassing it from 1st and into 2nd, then it starts in 2nd already pretty high in the RPMs so it picks right up and you don't experience sluggishness.

What are your thoughts? Perhaps my car will continue learning and adjust this behavior over time based on my driving.

By the way, the auto-stick is pretty darn cool. Thanks to Tartan Jack for the info in the sticky about it. I probably won't use it normally being a flatlander but it's fun to play with.
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J
You, hikingmike, are awesome! I thought I was the only automatic driver who put so much thought into observing shift points.

So, in order:

Coasting:
Give it a little gas to increase speed and force an upshift, then get off the gas, as when going down hill. It might not work at first, but I've read on the forums that the ECU learns the driver's habits. Eventually it will figure out you want to coast and upshift.

And give it more miles to get used to you. As the engine aged, my '08 automatic upshifted and coasted more willingly.

Strange revving:
Dunno; simplest explanation would be the gearbox hunting between 3rd and 4th. Same thing; give it time to break in or just use S-mode to force it into 3rd. Maybe rowing up to "S4" will help convince it to pick 4th instead of hunting.

Untimely downshifts:
This is interesting, because our transmission is actually a point of disagreement among the journalistic reviews. Some like the quick shifts, while others find it twitchy and slushy with exactly that tendency to be in high gear at low speed. My only suggestion is to use S-mode to force it into 2nd; eventually, the car should start to shift differently.

2nd gear, sluggish, then zoom:
I believe it's a limitation of having only 4 gears. In that sense, this issue is the same problem as above.

The simplest way I can put it is that: 2nd gear is the only speed gear, from 10mph to 65mph. No matter what, 4th is just top gear with barely any passing power, 3rd is barely short enough to climb hills with, and that leaves us with 2nd, and 2nd is long enough to provide acceleration at almost all common speeds.

Also, the automatic transmission downshifts into 1st. It's hard to realize, because that rush of speed after the shifting delay feels like 2nd, but in fact it's 1st.

If you have a chance, take an on-ramp at 20 and floor it up to 55. At the starting speed, the car will already be in 3rd or 4th doing about 1500rpm. Once you floor it, you'll get a shift delay, and then a walloping pull of acceleration with the engine quickly spinning up to 6500rpm, then another wallop for the upshift. That initial wallop was actually 1st gear. I've counted up, and 1st gear tops out at about 30mph, 2nd gear never really tops out, but once I let off the gas, it upshifts twice, to 3rd and then 4th, both of which gears don't really offer much passing power.
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hikingmike
Hey :) Thanks for the response! And I'm also glad to hear from someone else out there drives the automatic with similar attention.

JonCordova said:
Coasting:
Give it a little gas to increase speed and force an upshift, then get off the gas, as when going down hill. It might not work at first, but I've read on the forums that the ECU learns the driver's habits. Eventually it will figure out you want to coast and upshift.
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Sounds good, I'll work on it. I think I haven't done it this way before because it would make me go too fast (cops). However if I started out more aggressively it would upshift to where I felt was natural and then I could let off and not be going too fast at that point.

JonCordova said:
And give it more miles to get used to you.
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Yeah I figured this was part of it. It seems like the ECU is really good at learning from what I've been reading. This makes me wonder a bit if my driving habits are a little different from most people for them to set things this way initially.

JonCordova said:
simplest explanation would be the gearbox hunting between 3rd and 4th.
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That's my guess.

JonCordova said:
Also, the automatic transmission downshifts into 1st. It's hard to realize, because that rush of speed after the shifting delay feels like 2nd, but in fact it's 1st.
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Yeah I didn't put that in but I could tell it was downshifting multiple gears sometimes. That works for me.

JonCordova said:
This is interesting, because our transmission is actually a point of disagreement among the journalistic reviews. Some like the quick shifts, while others find it twitchy and slushy with exactly that tendency to be in high gear at low speed. My only suggestion is to use S-mode to force it into 2nd; eventually, the car should start to shift differently.
Click to expand...
Good to know about this. I think I do like the quick shifts (up and down) in general... but not the quick downshifts at lower speeds like after I'm making a turn. I knew exactly what gas pedal pressure would cause a downshift in previous cars but in this car and situation you don't have a choice - if you accelerate out of a turn it downshifts right away. Maybe I, or the car, will learn more and adjust to this.

JonCordova said:
I believe it's a limitation of having only 4 gears
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Yup makes sense. Though my previous cars also only had 4 gears. 5+ gear A/Ts are a lot more common recently. Probably combination of just 4 gears and low torque at low RPMs in 2nd.

JonCordova said:
If you have a chance, take an on-ramp at 20 and floor it up to 55. At the starting speed, the car will already be in 3rd or 4th doing about 1500rpm. Once you floor it, you'll get a shift delay, and then a walloping pull of acceleration with the engine quickly spinning up to 6500rpm, then another wallop for the upshift. That initial wallop was actually 1st gear.
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Ok will do :) I did similar from maybe 45 to 75 in my test drive. There is a very convenient stretch of interstate right next to the dealer.
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T
Having bought a '11 recently, one thing I have noticed that might be what is confusing you. When in 4th gear, it has a lock up for the converter. This basically locks the converter from slipping and in turn, lowers the RPM's (better mileage) and decreases the heat in the trans (no slipping converter).What I find is at cruise in 4th, if I give it a light amount of gas (like to increase speed or a slight grade), the lock up will turn off and the RPM's will jump up about 300 RPM's or so. This is not an actual downshift but if you are watching the tach, it seems like it is. Downshifting into 3rd is like an 800-900 RPM jump.Most modern trans have had lock up converters for a while. Some are better than others.Also, the engine has VVT (variable valve timing). I believe this "kicks in the cam" about 3500 RPM's. This allows a less powerful lower RPM range (better gas mileage) if you keep your foot out of it but if you need the power, once you hit the VVT range, it ramps up the cam for more power, hence that feeling like someone starting pulling you faster. Turbo engine has this similar issue with turbo lag.As stated above, the trans is a learning trans so it will take a few thousand miles to learn your driving habits. Hope that helps.
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erozcs
this is good stuff. thanks for starting this thread!

i experienced alot of what's being discussed here, but didn't understand the technology behind it. during my first couple of yrs of ownership i was back & forth to the dealer trying to figure out what was going on with my tranny. i wasn't satisfied with the generic explanations they had. finally talked to a master tech that explained things in a practical way that i could understand. it changed the wayi drive my B; i liked it even better.

i feel more in control now that i understand what's going on internally with the ecu, engine, & tranny. others will benefit from this thread.
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NITROBUSA
Ive got a adaptive auto in our 4x4 so was kind of use to it.
In saying that the rukus is different again.

I've noticed a few issues since I have fitted the 19s, a couple times going down a hill on way home from work it has either dropped from 4th or unlocked the lockup, then goes back to what it was doing, haven't quite noticed but I think I had cruise control on?

Also the gear change around 45km is more noticeable with the 19s.
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hikingmike
tikibox said:
Also, the engine has VVT (variable valve timing). I believe this "kicks in the cam" about 3500 RPM's. This allows a less powerful lower RPM range (better gas mileage) if you keep your foot out of it but if you need the power, once you hit the VVT range, it ramps up the cam for more power, hence that feeling like someone starting pulling you faster.
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Wow the cam kicking in! That sounds right to me now. I am no expert but I've learned what a DOHC feels like on my parents' Taurus :)

The converter lock sounds interesting. Great info with the cruise control demo. I'll keep a closer eye on RPMs when I can, and especially when trying to repeat the RPM oscillations to see how much it is.

erozcs said:
talked to a master tech that explained things in a practical way that i could understand. it changed the wayi drive my B; i liked it even better. i feel more in control now that i understand what's going on internally with the ecu, engine, & tranny. others will benefit from this thread.
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That's great, good to hear. I can look forward to both me and my car learning a bit over time and making things "feel right".
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NITROBUSA
Noticed another one today, if coasting down a slight incline and still have the excelerator pushed, but neither excelerating or decelerating, the auto chucks a spaz & dont know weither to drop a gear or stay?
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juddsandage
heh sorry, when you guys say the that the VVT "kicks in the cam" am am only reminded of the old saying "V-Tech Kicked in Yo!"

But on a serius note, I have notice that when my B is on an slight incline (like the off-ramp next to my work) that sometimes when I let off the brake and go to give it a little gas, it doesn't seem to do anything at all, I have to give it a bit more gas before the car actually moves. I'm wondering how much of that is normal idiosyncrasies of the trans or from the VVT-I cause I just bought this thing used like 2 weeks ago so it still has the learned behavior from the previous owner.
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J
juddsandage said:
...when my B is on an slight incline (like the off-ramp next to my work) that sometimes when I let off the brake and go to give it a little gas, it doesn't seem to do anything at all, I have to give it a bit more gas before the car actually moves. I'm wondering how much of that is normal idiosyncrasies of the trans or from the VVT-I cause I just bought this thing used like 2 weeks ago so it still has the learned behavior from the previous owner.
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From a complete stop on a steep hill, right?

I wouldn't be too worried about it; any automatic car will roll backwards at idle. The hill just has to be steep enough. You can hold an automatic stationary on a steep hill by using just the accelerator, giving it just enough gas to overwhelm the hill but not move forward.

As long as it downshifts when you floor it and screams up to redline, I'd say the transmission is fine.
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H
Great post dude I also get what you mean when coasting speed drops...I thought ot was odd at first but after driving it u get used to it lol .......only issue im having with my tranny is that when shifting into park the lever feels weird and wont shift into P. I have to play with it go up and down till it goes into P.
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hikingmike
I have to say since I've been paying more attention, I definitely notice the lockup that tikibox mentioned with the 300-400 RPM jump. Just gassing a little at cruising speed in 4th will cause it. That could have been what the RPM oscillation was. It is certainly noticeable enough. Also, I've used the autostick a bit more and it helps with the car upshifting (and then downshifting) when I don't want it to so I can take turns much better (when I use it). The automatic and I are seeing a little more eye to eye also and many times now it hasn't downshifted unnecessarily when I gassed slightly in 4th after coasting so that's good. I still have to get the slowing during coast figured out though. Since I've been using the auto-stick I know the slowing feels just like a downshift during coast so it's like it didn't go up to the next gear for better coasting. Perhaps it does that since it would need to drop 2 gears otherwise. I'm still not sure though. Sometimes it does it and sometimes it doesn't. I do know it's always there when dropping to 31mph while coasting, which is in 2nd I guess.

The way I can describe it is that it felt like the car was setup for those annoying drivers that stay close behind people and constantly hit the brake and the gas, and negatively affect my zen smooth driving :)

I agree with JonCordova about the steep hill. juddsandage said slight incline though. Anyway, it sounds pretty normal and I thought the xB actually picked up speed pretty quickly in idle compared to others.
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hikingmike
hidkid said:
Great post dude I also get what you mean when coasting speed drops...I thought ot was odd at first but after driving it u get used to it lol .......only issue im having with my tranny is that when shifting into park the lever feels weird and wont shift into P. I have to play with it go up and down till it goes into P.
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It sounds like you should take it in for warranty work for that! If you have my luck though, it won't do that at the shop when you need it to.

I actually just had one instance where I couldn't get my key to turn to start the car for several tries. Maybe it was the heat. That scares me a little. I know you have to push it in to get the key out after turning it off so maybe it was something related to that locking.
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hikingmike
Now that I've had my box for over a year, I thought I'd follow up on this. The xB and I have gotten more accustomed to each other and these have lessened a bit but I still see some and I guess that's just the way things are.

Up and down revs when lightly pressing gas to maintain speed:
I still have the issue of the car revving (hunting between 3rd and 4th) though not as often as I avoid it more now. My wife noticed it just recently. To a passenger, it's like "what the heck are you doing?", while I'm just holding my foot lightly on the gas. I do this to maintain speed on a downhill, where if I let off the gas I'd slow a bit, but if I hit the gas more I'd accelerate. Now I just try to avoid that situation and hit the gas more or let it off all the way and then go back on it when the hill flattens out.

I have observed the 300 RPM tach jump for the "lock up for the converter" that tikibox mentioned and that is not the same issue. It's more than 300 RPM.

Untimely downshifts:
This still happens occasionally but either I, or the car, or both have adjusted some so it's not a big deal anymore. I know when the car is going to shift now. I still should use the autostick more though. It was money in the Smoky Mountains last fall.

I do still have the occasional slow shift and slightly jerky behavior if I've been coasting up to some slower traffic and then hit the gas again as they move forward. This happened a bit in my last car too though. Hitting gas after coasting a little sometimes induces a bit of a jerk.

No coasting:
I hardly notice this anymore. I probably just got used to it. I drove my wife's MINI again and I still slow down in it unexpectedly early if I'm going slow enough speed pulling up to a stop sign or something.

2nd gear, sluggish, then zoom:
Well I am used to the acceleration in all situations now. I wouldn't be able to tell you if anything changed. I know it still pulls harder when higher up in 2nd when the "cams kick in".

I probably still need to adjust a bit how I drive, basically to do a little more gas-brake I guess. I don't want to be one of those people though :)
Oh yeah and in another thread it was mentioned to try turning off the traction control for a different problem but I think I'll give it a try and see if I notice a difference (besides the obvious traction control actions).
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G
+1 :cheers:
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markio
I'm 2000 miles in and the no-coasting thing is definitely noticeable. The moment I let off the gas it lurches upwards and starts to slow. I don't know if I dislike it. I use my brakes less often in stop-and-go and I guess that's kind of nice.

How would you guys characterize the car's sound? Is it rumbly? I came from a Subaru boxer engine and of course I love that rumble young man rumble.
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hikingmike
markio said:
How would you guys characterize the car's sound? Is it rumbly? I came from a Subaru boxer engine and of course I love that rumble young man rumble.
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Well I'd say that my stock exhaust has a pleasant low purr to it :)
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hikingmike
It's been a while and I thought I would update this again with my current experience since I had it in mind lately. Both I and the car have probably learned from each other now that I'm almost at 25,000 miles and 2 years.

2nd gear, sluggish, then zoom: This is probably the most interesting one to me. I can change my mind here now and I think it's completely the car that has adapted in this instance. I previously said:
"If I hit the gas harder after the shift to 2nd, it won't respond much until it gets to 3500RPM. At that point it feels like an imaginary rope starts pulling the car on faster. Woo, fun."
Click to expand...
Now I notice that I can hit the gas right after the shift and it responds! That's what I like. It's hard to describe, but I know when I can do it.

No coasting: eh, I don't really notice this anymore as I am completely used to how it behaves, and it probably coasts a little more also. Nothing to see here.

Up and down revs when lightly pressing gas to maintain speed/gearbox hunting between 3rd and 4th: I still can have this on rare hills where I'm just lightly pressing to maintain speed. I know about this and mostly now what I do is just not use the gas that lightly. I either hit it and gain a little speed, or let off all the way and slow down a little, to just gas later when the hill is ending. This way I'm helping out the car I guess.

Untimely downshifts: This still annoys me a little, mostly the shifting right out of turns. I like the auto-stick and that solves it but I actually don't use it that much.
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G
In 30+ years of car ownership, my XB is my first automatic and not a day goes by when I don't curse at the tranny. I should have bought the stick but I let the dealer and girl friend talk me into an auto. Mental note, never go car shopping with the girl friend.

Going around a corner and rolling on throttle just plan sucks, some times I get to stay in 2nd and accelerate smoothly and pretty quickly and other times it hesitates for second and I'm left in limbo waiting for it to get into 1st. I've had the car for 3K, wish the tranny would learn already. I'm thinking of doing an IS250 steering wheel mod for the paddle shifter just to manage corners better without having to reach over and drop it into sport mode.

I will say, 3rd is my favorite gear for back country windy roads, I just put it sport mod and leave it 3rd. Seems to have the perfect amount of engine braking and power. Many of my favorite roads I can zip through 50-70 mph and only have to tap the breaks for serious turns. No problems keeping up with my manual driving friends.

I also have to say the XB has quite a bit of hill climbing grunt for a four banger, I have surprised quit a few people with its ability to pass people on canyon climbs.
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5zero4
Use the sport mode to shift for a few days and it will speed up the learning process. I'm at 50k miles now and it's pretty much perfectly predictable in regular auto mode. After a day of autox it was even better. The is250 steering wheel is cool, but the paddle shifters is not really something I use regularly. But the steering wheel itself is so much better than the stock wheel in terms of look and feel.
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