Engine, Drivetrain & Forced-Induction
Have Technical Questions or Done Modifications to the G37? Find out the answer in here!

Are You Guys Feeling This - Problems with Lagging Tranny?

Thread Tools
 
Search this Thread
 
Old 07-17-2010, 02:31 PM
  #46  
cdso
Registered User
 
cdso's Avatar
 
Join Date: Feb 2010
Posts: 293
Likes: 0
Received 0 Likes on 0 Posts
I agree. The 7AT was a bad move from Infiniti. Why couldn't they just add one gear instead of 2. I see it as more of a programming issue. From what's I've experienced the tranny gets caught in the wrong gear when slowing down, thus when you try to accelerate, there's not enough grunt. Also, getting the 7AT to kick down when in top gear takes a strong right foot. I've been caught in situations where I've tried to merge onto a highway only to find the tranny not kicking down.

I have hfcs and Tanabes. It does help a little, but not a lot in my mind. Full auto mode is great on the highway unless you need it to kick down. Other than the highway, I use manual mode. It's kind of a situation where I've accepted it for what it is.
Old 07-17-2010, 03:06 PM
  #47  
shank
Registered User
 
shank's Avatar
 
Join Date: Jan 2010
Location: Southern California
Posts: 33
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by surfjax87
The worst lag for me is accelerating after almost stopping, like under 10 mph.
This is the issue I experience the most. Southern California traffic is awful for this tranny because it's typically 15mph down to a complete stop, then roll 5mph then quickly up to 35mph followed by nearly locking up the binders...rince and repeat... To me, it feels like the tranny goes into spasms because it can't figure out which gear to go into... As others have alluded to, I think the tranny wants to get to 7th as fast as it can for fuel economy. At normal highway speeds and driving around town, however, I haven't experienced significant issues... In the last week, I've started to drive in DS in traffic and it seems to help a bit - that and using the paddles in manual mode...
Old 07-17-2010, 03:54 PM
  #48  
ged1067
Registered User
 
ged1067's Avatar
 
Join Date: Nov 2009
Location: S. Florida & Poconos, PA
Posts: 129
Likes: 0
Received 0 Likes on 0 Posts
IDK if this is the same problem, but I had a scary experience. I driving on the skyline drive in the VA mountains having a glorious time on the curvy ups and downs: driving in DS and doing the gears the way I feel it should be done: mostly in 4 and dropping down to 3 for oncoming curves with a fast response to 4th when in the middle of the curve.

Coming around a curve in 3rd I came upon a Stop sign sooner that I expected so I paddled it down to slow down before braking. Wow, the car felt like it was in neutral for a few seconds before the downshift took and I flew right past the Stop sign and only my laundress willknow how I felt. Luck was with me and there were no oncoming cars. I thought I was a goner.

GED
Old 07-17-2010, 06:09 PM
  #49  
owslystnly
Registered User
 
owslystnly's Avatar
 
Join Date: May 2010
Location: rochester ny
Posts: 273
Likes: 0
Received 2 Likes on 2 Posts
werd...shoulda got a 6mt...but try that in NJ or NORTHEAST where dealers mostly stock X's and not many rwd- forget 6mt..."oh we'll have to special order that and it could take weeks to locate one.."blah blah.... next go round will absolutely be 6mt.
I am in the northeast, so I drove down to DC-area to get mine........
Old 07-17-2010, 09:37 PM
  #50  
15951
Registered User
 
15951's Avatar
 
Join Date: Apr 2005
Posts: 563
Likes: 0
Received 6 Likes on 5 Posts
Originally Posted by ged1067
Coming around a curve in 3rd I came upon a Stop sign sooner that I expected so I paddled it down to slow down before braking. Wow, the car felt like it was in neutral for a few seconds before the downshift took and I flew right past the Stop sign and only my laundress willknow how I felt. Luck was with me and there were no oncoming cars. I thought I was a goner.

GED
The car will blip the throttle before downshifting for rev matching (which is awesome, btw). I think that's what you experienced.

Regardless, you should have been on the brakes if you needed to stop that soon.
Old 07-18-2010, 12:21 AM
  #51  
lkevinl
Registered User
 
lkevinl's Avatar
 
Join Date: Jul 2010
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by ged1067
Coming around a curve in 3rd I came upon a Stop sign sooner that I expected so I paddled it down to slow down before braking.
Hey man, brake pads are cheaper than engines and trannys!!

Hi all, I'm new here! I'm in a BMW 335i right now thinking about taking the plunge on the G37 sedan to save some money on monthly payment but still be able to drive a fun, fast car.

This issue is concerning for my decision! In my 335 (6AT), DS mode never sees 6th and in general is always 1 gear below where it would be under the same conditions in D mode when not accelerating. Of course, the other difference is that DS mode up-shifts more aggressively at higher RPMs then in D mode. Punching it in D vs. DS shows very little difference when it comes to responsiveness. DS mode is also always 1 gear closer on the downshift than D when punching it (5th to 4th vs. 6th to 4th) which can some times make D feel like it lags more.

In some of the examples given by others here about changing lanes and punching it, in my 335, my habit in that situation is to switch to DS mode for the more aggressive up-shift, but not to eliminate any lag.

So, is the consensus here that in the G37, switching to DS mode eliminates the lag feeling substantially (or sufficiently) or is it still an issue in DS mode. This would make a difference for me because if this is a non-issue in DS mode, my driving habit from my 335 is to shift into DS anyway during those situations. As a matter of fact, in the city I use DS all the time and only shift to D on the highway to save gas.

Thanks in advance!
Old 07-18-2010, 01:42 AM
  #52  
HappyG
Registered User
 
HappyG's Avatar
 
Join Date: May 2010
Location: New York
Posts: 597
Received 2 Likes on 2 Posts
Originally Posted by lkevinl
As a matter of fact, in the city I use DS all the time and only shift to D on the highway to save gas.
Traffic condition here in NYC area is nasty most the time. I too use DS to get out of situations and then switch to D during free flow traffic.

If you are interested in getting a G, why not test drive one. Try both D and DS mode. That is the only way to see if it will work out for you.
Old 07-18-2010, 02:47 AM
  #53  
lkevinl
Registered User
 
lkevinl's Avatar
 
Join Date: Jul 2010
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by FishMeetFish
Traffic condition here in NYC area is nasty most the time. I too use DS to get out of situations and then switch to D during free flow traffic.

If you are interested in getting a G, why not test drive one. Try both D and DS mode. That is the only way to see if it will work out for you.
Hmmm, did test drive twice but to be honest, I didn't play with DS or paddles much. I should have asked to take it on the freeway too. Good suggestion. I'm thinking with my driving habits, I might not notice the lag issue... just take advantage of the fuel economy on the freeway and spend the rest of the time in DS mode.
Old 07-18-2010, 09:12 AM
  #54  
KLB
Registered User
 
KLB's Avatar
 
Join Date: Mar 2009
Location: Chicagoland
Posts: 700
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by lkevinl
Hey man, brake pads are cheaper than engines and trannys!!

Hi all, I'm new here! I'm in a BMW 335i right now thinking about taking the plunge on the G37 sedan to save some money on monthly payment but still be able to drive a fun, fast car.

This issue is concerning for my decision! In my 335 (6AT), DS mode never sees 6th and in general is always 1 gear below where it would be under the same conditions in D mode when not accelerating. Of course, the other difference is that DS mode up-shifts more aggressively at higher RPMs then in D mode. Punching it in D vs. DS shows very little difference when it comes to responsiveness. DS mode is also always 1 gear closer on the downshift than D when punching it (5th to 4th vs. 6th to 4th) which can some times make D feel like it lags more.

In some of the examples given by others here about changing lanes and punching it, in my 335, my habit in that situation is to switch to DS mode for the more aggressive up-shift, but not to eliminate any lag.

So, is the consensus here that in the G37, switching to DS mode eliminates the lag feeling substantially (or sufficiently) or is it still an issue in DS mode. This would make a difference for me because if this is a non-issue in DS mode, my driving habit from my 335 is to shift into DS anyway during those situations. As a matter of fact, in the city I use DS all the time and only shift to D on the highway to save gas.

Thanks in advance!
What you describe is pretty much exactly how I drive my G. I personally do not experience much of what is being discussed here.

I suggest you take a G out for a good test drive and see what you think.
Old 07-18-2010, 11:09 AM
  #55  
Almatti
Registered User
Thread Starter
 
Almatti's Avatar
 
Join Date: Jun 2010
Location: New York Metro Area
Posts: 604
Received 4 Likes on 3 Posts
Almatti here, This Thread starter.....The response is amazing. Goes to show the "silent majority" out there with dissatisfaction with the 7spd tranny. The recent posts center on the lack of response on the "kickdown" at highway speeds. That seems to happen more in D Mode, a little better in DS mode. The member that described the Bimmer's D and DS modes, i think has it about right concerning the Gs too. DS seems to be one gear lower at certain speeds - mostly at 40 to 50 mph. I noticed and played with this yesterday. In DS mode and then shift up doing 40 or so, you shift up into 5th gear. That's the dreaded gear in this tranny. it won't shift Up of course, speed is too slow, shift down to 4th and see the difference in performance...No you are in Manual Mode. Shift vack to D and then back to DS and see the difference and see that you are again in 4th gear, much more torque in that gear. But put 'er back into D mode, and throttle in and out and FEEL THE GEAR HUNTING AND HERKY JERKINESS OF THE TRANNY. Hate it. The 07 NEVER did that.

Let's keep posting the dissatisfaction here and elsewhere. Maybe Infiniti will Hear Us !!! Screw the 1 mie per gallon you might happen to enjoy - on the highway anyway. I only have about 1k miles on the clock as of today, but driving locally - punching it harder than when I first got it according to the advice of memebers here - I'm getting the same 12 mpg as I did on my 07 !!!
Old 07-18-2010, 01:15 PM
  #56  
gugarci
Registered User
 
gugarci's Avatar
 
Join Date: Jul 2007
Location: Bergen County, NJ
Posts: 541
Received 4 Likes on 3 Posts
In all fairness in my case I would not consider myself dissatisfy with this gearbox. No auto is gearbox is perfect but some of these things can be improved on.

Anyway I drive in manual 100% of the time on the hwy, unless I'm in bumper to bumper traffic. So the kick-down issues for me it's a non-issue. But I wish in DS mode it would not let the gearbox ever be under 2500RPM's regardless of your speed.
Old 07-18-2010, 02:15 PM
  #57  
BillPaul
Registered User
 
BillPaul's Avatar
 
Join Date: Jan 2010
Location: Southeast USA
Posts: 115
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by RedG37SNC
As if the 6MT doesn't have it's share of problems. Chatter, vibration, noise on 45K car.. laughable.
Actually, having a good time with my 6MT. The only thing I would change is I would like a taller 6th gear. Nevertheless, getting 21 mpg around town & 26 mpg on the road. Not bad for a 4 door hot rod.

I do find the complaints about the AT puzzling. e.g. Consumer Reports loved it when they took it on the test track. See CR Road Test + video of G37 sedan (for online subscribers):
Car Model Review - Consumer Reports

Does the AT not eventually "learn" your driving style?

Old 07-18-2010, 06:25 PM
  #58  
cvroom
Registered User
 
cvroom's Avatar
 
Join Date: May 2010
Location: Chicagoland, IL
Posts: 507
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by lkevinl

So, is the consensus here that in the G37, switching to DS mode eliminates the lag feeling substantially (or sufficiently) or is it still an issue in DS mode.
Thanks in advance!
using advice from this thread I have been shifting to "DS" to illiminate lag while moving and accelerating hard. Ive been trying to recreate scenarios where the trans did not respond well when it was in "D" and I have not noticed any lag so far. It seems to be a significant improvement when i switch to "DS".
Old 07-18-2010, 08:15 PM
  #59  
RISKY GUY
Registered User
iTrader: (9)
 
RISKY GUY's Avatar
 
Join Date: Jun 2009
Posts: 2,078
Received 43 Likes on 31 Posts
Originally Posted by ged1067
IDK if this is the same problem, but I had a scary experience. I driving on the skyline drive in the VA mountains having a glorious time on the curvy ups and downs: driving in DS and doing the gears the way I feel it should be done: mostly in 4 and dropping down to 3 for oncoming curves with a fast response to 4th when in the middle of the curve.

Coming around a curve in 3rd I came upon a Stop sign sooner that I expected so I paddled it down to slow down before braking. Wow, the car felt like it was in neutral for a few seconds before the downshift took and I flew right past the Stop sign and only my laundress willknow how I felt. Luck was with me and there were no oncoming cars. I thought I was a goner.

GED
im sure that lag is there to protect the engine & transmission.

I have a 5 a/t & have had similar issues, use the paddles.

the rev match will almost hold the engine speed, to make sure your ok to go into the gear.

I know exactly what you mean, I have some fly bys not cool.

Recently i was downshifting manually, i must have been going to fast for first.

when i downshifted it was on the way down from 2nd to 1st.

but it would not go into 1st gear the indicator just flashed then dropped to 1st.

I have had the car for 3 years, never had that happen.
Old 07-18-2010, 08:39 PM
  #60  
movinon
Registered User
 
movinon's Avatar
 
Join Date: Mar 2010
Posts: 776
Likes: 0
Received 6 Likes on 5 Posts
No lag complaints from me.
I have a 2010 Sedan, 7 speed auto, with 6,000 miles on it. Two weeks ago I came back from a 4,000 mile trip, of which approximately 1,000 miles were 2 lanes. I did "A LOT" of aggressive passing on the 2 lanes.
The transmission was always in D. I never experienced any lag when I floored the throttle. I don't like to waste any time when I pass on 2 lanes, but I actually started easing off the throttle sooner, because I was getting up in the 100-115 mph range during my passes.


Quick Reply: Are You Guys Feeling This - Problems with Lagging Tranny?



All times are GMT -4. The time now is 06:36 PM.