Really, it's quite simple. DS is performance, D is fuel economy. Only time i'm in D is on the highway to keep it from downshifting on traffic lulls. If you still have lag in DS, get a tune.

 

The worst lag for me is accelerating after almost stopping, like under 10 mph. The transmission just doesn't want to drop to 1st gear. It takes a second or two before I actually start accelerating. I've learned to move into DS and drop it into 1st myself for that.

 

surfjax: Correct, that too is a big problem that is experienced in D or DS without going into Manual shifting. There should be no need to do that in just non-spirited local driving. I hope Infiniti is monitoring this Forum and particulalry this thread. Man, it's been active !! Thanks for the feedback.

 

REDG37: This has nothing to do with getting a Tune....The performance is being compared to the 07 G35 models. The 08s were already modified (de-sensitized the throttle - I felt immediately when I had loaners). There is lag & hesitation... My advise to Shoppers, take it for long - numerous test drives, to see if your happy.

 

There's definately a coorelation between engine performance and transmission performance, with better throttle response it's possible the torque converter could lock quicker and thus remove or reduce the lag. One user already mentioned adding bolts on helped, it would be interesting to hear from those with a tune if they still experience the lag.

 

you shoulda got the 6mt.......

 

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.

 

As if the 6MT doesn't have it's share of problems. Chatter, vibration, noise on 45K car.. laughable.

 

for sure. 92 octane, chevron. not that it really matters (brand).

on a side note, i can understand why hfcs and a cbe would cure the lag. better breathing. i can only imagine that there's tons of restriction headers back.

 

actually, i was going to say the same. question though: chatter from what? the valves? is that exclusive to the 6mts? vibration from...?

 

When you have a small number of cars experiencing these symptoms it's wear or contaminates.. when all cars experience it.. it's design. In a nutshell it's a poor design. Point is each has pro's and con's.. you just have to pick the one that best suits your needs.

 

Maybe you guys should try a tranny cooler?? just a thought! Don't flame me for it!

 

im sure a valve body upgrade would solve a lot of the problems the 7at guys are experiencing.

anyways, here is my opinion. i have had an 08 g35 sedan since Nov of 2007, last week i brought it in for service and got a g37 sedan as a loaner. the car moves, no doubt it has power....BUUUTTTTT, i prefer my 5AT tranny anyday over the new 7AT. i understand why infiniti changed it but the 5AT was one of, if not the best non-dual-clutch automatic tranny in any car. people drive my car who hate automatics and they dont mind it, they say theyre used to laggy, jerky, sluggish autos, and the nissan 5AT isnt any of those things. the 7AT would be perfect if it were just the 5AT with 2 extra gears and the ratios changed. idk the design too well but i def. felt it when driving the loaner.

btw, a 5AT with valve body upgrade, grounding wire (with ground to tranny), and tranny cooler is very comparable to a Volkswagen dual-clutch transmission found in the newer GTI's.

 

Yep - premium fuel for me each and every time.

I can't understand why I am not experiencing the same intensity of problems with my 7AT compared to others here - from reading the posts, it's clear that I don't have these things in the same way. Is it possible I have "taught" my transmission well enough?? It is extremely rare for me to have that 30-50 mph lag or the hiccup when stepping on the gas and a reluctance to downshift - I have experienced it but I must say it doesn't happen often. And I never drive in DS unless I am manually shifting.

My 7AT seems to upshift happily through the gears all the way to 6th and 7th (besides hanging on to 3rd gear FOR-EV-ER - my biggest gripe with the tranny) without lag. But then again, I am usually on the throttle "enough."

Curious about other's insights and experiences, too.

P.S. When you want to forget about the 7AT issues, manually shift up through the gears (early) when accelerating under 3/4 throttle - especially 3rd - 7th - and feel the tight, firm, quick shifts and how the 3.7 pulls like a locomotive even when you shift into 7th at around 70-75 mph. I am determined to love this 7AT.

 

My car has 17k miles so I guess I've either gotten used the lag or it has gone mostly away. But my biggest beef with the auto gearbox is that it tend to be in to high of a gear all the time. I should not be cruising around town in 5th or 6th gear.

But IMO the quickest way to get rid of the lag for passing is to downshift it manually. I drive this car 100% manually on the hwy and my car rarely see any gear higher than 5th. Unless I'm in a long trip and I'm just cruising along.