My M35x has been very well maintained and makes great power, engine very responsive, all gear oils changed with Matic/other correct fluids. The car has 108k miles, no diagnostic trouble codes/no ghost codes, and always run 93 octane. I do have a few extra grounds that I have added and cleaned up, but none relating the the throttle or the transmission directly. I have reset the throttle body and have a new afm so the torque calculation for the transmission/shifting should be pretty good.
Suppose you are cruising in 5th gear at 40-50 mph at about 20% throttle. You want to accelerate/overtake somewhat briskly and put it down to 60-70% throttle.What usually happens is the transmission remains in 5th gear and isnt very responsive, then after a second will kick down to 4th,for 1/4 of a second then kick down to 3rd and rapid acceleration commences.
I know the 5AT is dated technology but my 2006 Toyota Minivan has a much more crisp feeling transmission. It will downshift readily and does so smoothly and quickly.
Is our 5AT just not that refined? I do notice much cleaner/smarter/less boggy shifting and kickdowns after an ecu reset. I have consulted the google machine and see similar things on many other makes and models of cars where the shift quality/behavior is much improved after a reset. It makes it feel like I have more low end grunt because its not trying to lug around in 5th for a bit when i want to accelerate
The thing that makes me irate is that the internet collectively says "ya, its an adaptive transmission and it learns n stuff, so u gotta drive it like u stole it lol" the service advisor at the infiniti dealer told me the same thing, just without the "lol" because he was wearing a suit and trying to be professional.
Now, I am not an automatic transmission expert, but I have a hard time believing in the transmission adapting/learning like all the chain-vaping street race guidos of the internet would regurgitate: which is "if you reset your ecu and drive like a grandma, your shifts are going to be slow, so u gotta like drive it hard for like 500 miles dude" ....bullhonky. I can imagine the adaptation being more along the lines of the pressure transducers delivering information that the TCM uses to trims the hydraulic pressure to make the shifts a little cleaner, then stores that trim after analyzing "x" number of shift sequences. That and "adaptive" in terms of having maybe 2 different algorithms and shift point maps for when you are driving aggressively vs sedately. ANYWAYS
Is this at all normal? my only comparison is a 2003 maxima from 16 years ago that seemed more punchy on the low end.
I will be doing a smoke test, replacing the knock sensor, and knock sensor harness just because im OCD and dont want to be stumbling into a slight lean surge or timing retard that prolongs the torque calculation and response from the transmission
M35x Transmission Behavior, Is this normal?
Re: M35x Transmission Behavior, Is this normal?
Suppose you are cruising in 5th gear at 40-50 mph at about 20% throttle. You want to accelerate/overtake somewhat briskly and put it down to 60-70% throttle.What usually happens is the transmission remains in 5th gear and isnt very responsive, then after a second will kick down to 4th,for 1/4 of a second then kick down to 3rd and rapid acceleration commences.
What you describe sounds like the Downshift Rev-Match feature these cars have kicking in.
I know the 5AT is dated technology but my 2006 Toyota Minivan has a much more crisp feeling transmission. It will downshift readily and does so smoothly and quickly.
Actually, Rev-Match is a more modern feature that is now seen in the lineups of many auto manufacturers
Is our 5AT just not that refined? I do notice much cleaner/smarter/less boggy shifting and kickdowns after an ecu reset. I have consulted the google machine and see similar things on many other makes and models of cars where the shift quality/behavior is much improved after a reset. It makes it feel like I have more low end grunt because its not trying to lug around in 5th for a bit when i want to accelerate
Rev-Match is calculating your engine rpms to your transmission downshift request to give a smooth transition in matching the speeds of these units so you do not expose the transmission to excessive loads & shock during the downshift. Great for improving wear and tear on the unit, and actually gives a smoother transition I think you describe as loosing "crispness" in the shift, as compared to your minivan.
The thing that makes me irate is that the internet collectively says "ya, its an adaptive transmission and it learns n stuff, so u gotta drive it like u stole it lol" the service advisor at the infiniti dealer told me the same thing, just without the "lol" because he was wearing a suit and trying to be professional.
Now, I am not an automatic transmission expert, but I have a hard time believing in the transmission adapting/learning like all the chain-vaping street race guidos of the internet would regurgitate: which is "if you reset your ecu and drive like a grandma, your shifts are going to be slow, so u gotta like drive it hard for like 500 miles dude" ....bullhonky.
This transmission is robust, but certainly could be made into a pile of rubbish by street racers trying to make this transmission perform in an environment is was not made for. It is not a transmission built for racing.
I can imagine the adaptation being more along the lines of the pressure transducers delivering information that the TCM uses to trims the hydraulic pressure to make the shifts a little cleaner, then stores that trim after analyzing "x" number of shift sequences. That and "adaptive" in terms of having maybe 2 different algorithms and shift point maps for when you are driving aggressively vs sedately. ANYWAYS
You are pretty much on target with the above, putting it simply. I am sure it is more complex then just a few algorithms...and the main purpose of learn block is for emissions control & driveability. For example, best shift patterns based on your RPM input & engine load. Driving like grandma vs rocket racer are two extreme ends that the ECM/TCM needs to define to correlate best shift patterns to keep emissions under control & still give you respectable driveability.
Is this at all normal? my only comparison is a 2003 maxima from 16 years ago that seemed more punchy on the low end.
I am not saying you do not have a problem, but I just do not see it here...from what you describe, I feel I could say the same about my M's shifting.
My wife drives my M much more aggressively then I do. After she drives it for several hours, I do feel shift patterns are firmer & quicker next time I get behind the wheel.
I will be doing a smoke test, replacing the knock sensor, and knock sensor harness just because im OCD and dont want to be stumbling into a slight lean surge or timing retard that prolongs the torque calculation and response from the transmission.
Smoke test, knock sensor & harness, stumbling light lean surge, timing retard..all you left out was fuel octane as a possible root cause!
What you describe sounds like the Downshift Rev-Match feature these cars have kicking in.
I know the 5AT is dated technology but my 2006 Toyota Minivan has a much more crisp feeling transmission. It will downshift readily and does so smoothly and quickly.
Actually, Rev-Match is a more modern feature that is now seen in the lineups of many auto manufacturers
Is our 5AT just not that refined? I do notice much cleaner/smarter/less boggy shifting and kickdowns after an ecu reset. I have consulted the google machine and see similar things on many other makes and models of cars where the shift quality/behavior is much improved after a reset. It makes it feel like I have more low end grunt because its not trying to lug around in 5th for a bit when i want to accelerate
Rev-Match is calculating your engine rpms to your transmission downshift request to give a smooth transition in matching the speeds of these units so you do not expose the transmission to excessive loads & shock during the downshift. Great for improving wear and tear on the unit, and actually gives a smoother transition I think you describe as loosing "crispness" in the shift, as compared to your minivan.
The thing that makes me irate is that the internet collectively says "ya, its an adaptive transmission and it learns n stuff, so u gotta drive it like u stole it lol" the service advisor at the infiniti dealer told me the same thing, just without the "lol" because he was wearing a suit and trying to be professional.
Now, I am not an automatic transmission expert, but I have a hard time believing in the transmission adapting/learning like all the chain-vaping street race guidos of the internet would regurgitate: which is "if you reset your ecu and drive like a grandma, your shifts are going to be slow, so u gotta like drive it hard for like 500 miles dude" ....bullhonky.
This transmission is robust, but certainly could be made into a pile of rubbish by street racers trying to make this transmission perform in an environment is was not made for. It is not a transmission built for racing.
I can imagine the adaptation being more along the lines of the pressure transducers delivering information that the TCM uses to trims the hydraulic pressure to make the shifts a little cleaner, then stores that trim after analyzing "x" number of shift sequences. That and "adaptive" in terms of having maybe 2 different algorithms and shift point maps for when you are driving aggressively vs sedately. ANYWAYS
You are pretty much on target with the above, putting it simply. I am sure it is more complex then just a few algorithms...and the main purpose of learn block is for emissions control & driveability. For example, best shift patterns based on your RPM input & engine load. Driving like grandma vs rocket racer are two extreme ends that the ECM/TCM needs to define to correlate best shift patterns to keep emissions under control & still give you respectable driveability.
Is this at all normal? my only comparison is a 2003 maxima from 16 years ago that seemed more punchy on the low end.
I am not saying you do not have a problem, but I just do not see it here...from what you describe, I feel I could say the same about my M's shifting.
My wife drives my M much more aggressively then I do. After she drives it for several hours, I do feel shift patterns are firmer & quicker next time I get behind the wheel.
I will be doing a smoke test, replacing the knock sensor, and knock sensor harness just because im OCD and dont want to be stumbling into a slight lean surge or timing retard that prolongs the torque calculation and response from the transmission.
Smoke test, knock sensor & harness, stumbling light lean surge, timing retard..all you left out was fuel octane as a possible root cause!
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Larz
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Re: M35x Transmission Behavior, Is this normal?
Steve hit it right on it's head. Our cars don't have dual clutches, super chargers, etc that allow for instant responses. They are among the oldest 7 speed gear boxes out there and so they don't have the best or smoothest transitions. I still find, on rare occasions, that my gear box takes a pause, as if it's thinking: "hmmmm we're going at 60 and he has mashed the pedal ... what do I do now? .... wait, I know this ... oh yes! Give it the beans! "
Perhaps yours is a bit slower to react than it used to, but it doesn't sound to me that is is malfunctioning. It may be worth having the dealer do a complete diagnostic. It will result in some sort of labor charge, but at least you will know if there is an issue.
Perhaps yours is a bit slower to react than it used to, but it doesn't sound to me that is is malfunctioning. It may be worth having the dealer do a complete diagnostic. It will result in some sort of labor charge, but at least you will know if there is an issue.
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pedsemdoc
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Re: M35x Transmission Behavior, Is this normal?
This is so very true which makes your perception relative. I thought my '06 M45 was pretty quick with loads of torque, then I thought my '13 M37 was just as fast without as much torque, BUT compared to my '14 Audi RS7 with a 4.0 twin turbo V8.....
(blink of an eye and you're at triple digit speeds) the HP and torque is instantaneous AND ridiculous, and when its in dynamic mode - the exhaust burbles and pops are better than the Bang & Olufsen 1440 watt 15 speaker system!! Certainly changing out the items you mentioned might make some improvements, and certainly making sure that there haven't been any TCU updates for your year/model should help too - the dealer should know if there are any.