Transmission rough shifting in cold weather

[LEXKYM45]

Hello everyone! New member and first post. Just purchased a used "06 M45 Sport off a 2 yr lease last month. Have had some hard shifts from 2nd to 3rd gear when weather outside is below 30 degrees. However, if the M has warmed up for 5 mins or longer , the shift is smooth. Will be taking to dealer for 30k mile service soon to check out. Anybody else having the same issues ? BTW, I love the car! My neighbor has a "99 vette and he's been drooling over the M since I let him drive it. He couldnt believe how well it handled for that size of car.

[auditech10]

You diagnosed the car yourself it seems. You are SUPPOSED to let your car warm up as much as possible before you start driving it. It is considered extreme driving conditions when you get in and mash around in a cold car, you will find that things will wear out faster when you do this. 5 minutes is not really that long, is it????

[newkiebrown]

I did notice that if i'm in a rush to get moving (leaving cold) and i put the car in reverse it will shift hard and *thud* in to gear. After it warms up a bit it'll shift smooth.

However, I do NOT have hard up-shifting issues and I try my best to keep the rpm's low until she's all warmed up.

[LEXKYM45]

Thanks for the insight. I realized after haven driven V6's for years now it should take a little longer for the V8 to get up to temperature. Although it still seems odd for it to only make the "thud " noise only between 2nd and 3rd gear and not any other gears. I don't know. :got me

[nissan jedi apprentice]

like my dad always said, growing up in minnesota. "If i made you sleep in the garage when it's cold and then woke you up to go running at full speed with no wake up time, how would you feel? Keep in mind these are man-made machines and are not infalible.

[malexand7]

I recently purchased a used '06 M45 Sport and experience the same issue when manually shifting from 2nd to 3rd. It is the only gear that ever causes any problems. I get a hard thud when the shift occurs. The problem occurs whether the car is warm or cold. I'm going to have it checked out next week. I'll be sure to let you know what they say.

[szh]

I recently purchased a used '06 M45 Sport and experience the same issue when manually shifting from 2nd to 3rd. It is the only gear that ever causes any problems. I get a hard thud when the shift occurs. The problem occurs whether the car is warm or cold. I'm going to have it checked out next week. I'll be sure to let you know what they say.

Welcome to NICO!

Please let us know what the dealer says ...

Z

[Q45tech]

All modern electronic controlled AT since 1990 have an internal temperature sensor used by TCU to control shift pressure.

Depending on ATF temperature take a 5-10 minute period to reach operating temperature.

Remember each shift cycle costs 4.5 cents [replacement cost after 70k warranty is $4500 minimum]. Treat your AT right with fresh ATF every 30k/2years and it will last a lot longer and prolong the time when you get to spend the $4500.

[LEXKYM45]

My dealer service tech said pretty much the same thing as Q45tech. A warm up is crucial for proper shifting, especially in cold weather. Its all about fluid temp and pressure and low rpms. Also he noted that my transmission would not shift into 5th gear until up to a proper temperature. In other words, by not being in such a hurry and proper warm up the problem went away! Nice!

[jimcarden]

Hi:

Very curious what you found out, as I am now (after 2 years) experencing the very same problem. Sure would appreciate an update. You can email me at [email protected] if you would.

Thanks... Jim

[busaboy]

My 99 Q45 did and my 03 M45 does a similar thing. It is my opinion that Infiniti is trying to "light off" the Catalytic Converter so the engine will not exceed Emissions. It is due to the software for the transmission and engine. Once my Engine Water temperature gets close to normal, the transmission shifts normally. On my Q45 it used to drive me crazy since I thought the transmission was bad. I put 150K on the car and it always acted the same.

More disturbing is that my M45 will knock like crazy if you try to use too much throttle before the engine warms up. It is hard to believe, but I think the engine software ignores the knock sensors until the engine heats up. I have never had a modern EFI engine knock as bad as this car. Once warm, the car never knocks even with 89 octane fuel. I used to use 93 all the time, but the car does not seem to care.
Modified by busaboy at 5:17 PM 4/11/2008

[szh]

More disturbing is that my M45 will knock like crazy if you try to use too much throttle before the engine warms up. It is hard to believe, but I think the engine software ignores the knock sensors until the engine heats up. The software keeps the advance as is allowing the engine to warm up faster. I have never had a modern EFI engine knock as bad as this car. Once warm, the car never knocks even with 89 octane fuel. I used to use 93 all the time, but the car does not seem to care.

This strikes me more as the typical carbon buildup issue that these engines will sometimes get.

1. Try a few WOT runs (after engine is warm) and see if that clears it up.

2. If not, then a BG-44K session (or two) may be needed.

3. If two (maximum) BG-44K sessions do not work, do a powered rail flush.

And, of course, let the engine warm up a minute or two (gauge rises up a bit from the bottom ... does not have to be fully warmed up) before you start out and it will thank you!

Z

[busaboy]

The M45 never knocks when it is warmed up. It will knock like crazy if I nail the throttle before the temp gage is near the middle range. You really think this is carbon build up? I would think it would knock worse when the engine got hot and the hot carbon causes detonation. To me it seems like the ECU is ignoring the knock sensors or is setting the advance too high trying to warm the engine or CATs up.

I used to nail the throttle on 99 Q45 when the engine was cold all the time. It never knocked. The transmission would stay in a lower gear longer until the engine warmed up.

[DashingMax]

I am having the exact same issue with the cold temperatures here in Chicago. Even after warming up for 5+ minutes, the first few times from 2nd to 3rd and sometimes even 3rd to 4th is jerky.

After full warm-up, it is buttery smooth!! Less than 30k miles right now. I will take all of your advise definitely get the transmission fluid replaced during my 30k service.

Cheers!

[szh]

After full warm-up, it is buttery smooth!! Less than 30k miles right now. I will take all of your advise definitely get the transmission fluid replaced during my 30k service.

Good!

Please make sure that they use Nissan Fluid J ... anything else will void the transmission warranty!

Z

[ArbitrageMan]

There is a TSB for this exact issue. Abrupt shifts from 2nd to 3rd while in D, in cold whether. The TSB states that if the tech can duplicate the issue, he should update the transmission software.

[DashingMax]

The only way to duplicate the issue is to let the car sit & get cold again. That means, dropping it off and making 2 different trips and...well...at least it is good to know that a simple software update will fix that!

You guys are very knowledgeable...impressive!

[tytamto]

There is a TSB for this exact issue. Abrupt shifts from 2nd to 3rd while in D, in cold whether. The TSB states that if the tech can duplicate the issue, he should update the transmission software.

Yep, I thought about doing the TSB, since my car does that too. But it is not worth it... all they do is soften up the shift by slowing it down (not good for transmission). I would much rather take a rougher shift when cold, than make my transmission even more lazy

Learn to live with it, and I promise that it will go away in a few months (at least for a while).

[M4T5]

I am having the exact same issue with the cold temperatures here in Chicago. Even after warming up for 5+ minutes, the first few times from 2nd to 3rd and sometimes even 3rd to 4th is jerky.

After full warm-up, it is buttery smooth!! Less than 30k miles right now. I will take all of your advise definitely get the transmission fluid replaced during my 30k service.

Cheers!

Hell..... sign me up for the snappy shifts software!!!!!!!!!

J

[2007 M45 Sportster]

I have a 2007 M45 Sport & I had a similar problem with rough manual shifting between 2nd & 3rd. Today, I took the car in to Infiniti of Tyson's Corner, Tyson's VA. They reprogrammed the TCU back to factory defaults & the problem has gone away. I am very happy. I'm not sure what happened to require the baselining of the software, but it fixed the problem.

I was told by their senior mechanic, that at this time I did not need a transmission flush. I was very supprised to hear this, considering this is a billable service. I was treated very fairly by the dealer.

I also had a problem w/ the as gauge. They also replaced the fuel sending unit

The work was all done under warranty. They took great car of my car.

[The00Dustin]

I was told by their senior mechanic, that at this time I did not need a transmission flush. I was very supprised to hear this, considering this is a billable service. I was treated very fairly by the dealer.

How many miles? I wanted my transmission flushed when I got it, and the girl that schedules appointments clearly didn't have a clue what that even meant, so it was only changed with the standard service (instead of being upgraded to a flush). I talked to the SA about getting it flushed and he said just changing the 4 quarts is fine and they really don't need flushed (and even suggested some people have had trouble because of a flush, which I have always understood to only be a potential problem when the fluid has never even been changed and there are a lot of miles [100K+] on the thing), but everyone on here says they ought to be flushed with some degree of regularity. I asked why there would be a flush procedure in the FSM if it was absolutely unnecessary, and his response was that some people want it done anyway, so they need to have a procedure. All of that said, to those who recommend a flush every so often, is this something you recommend the dealer do, or would a third party be fine?

[dvan]

More disturbing is that my M45 will knock like crazy if you try to use too much throttle before the engine warms up. It is hard to believe, but I think the engine software ignores the knock sensors until the engine heats up. I have never had a modern EFI engine knock as bad as this car. Once warm, the car never knocks even with 89 octane fuel. I used to use 93 all the time, but the car does not seem to care.

Modified by busaboy at 5:17 PM 4/11/2008

Yeah, I know this is an old thread but I believe I have the same issue with my M45 in the morning. Turn the radio off when i pull out of my driveway and hit the gas and I can hear a rapid high pitch 'tick' sound that matches my RPMs. Is this something that be fixed under power train warranty?

I also have the hard shift from 2-3 in manual mode...good thing i am learning all this before I hit 70K in a few months!!