Jittering around 36-38mph and ~1500rpm '06 M35x

[Shinobi326]

I'm starting a new thread because my response is fairly buried in my old thread about warranty stuff.

I just got back from the dealership and here is the story. The service manager asked if he could drive the car home and back and really spend some time with it to see if anything else is going on; I agreed to that. The SM and the master tech there spent two hours this morning driving my car as well as another used 2006 M35x they had on the lot to see if there is any similarity.

Well apparently there is some similarities. This might simply be a AWD thing, but both cars apparently experience this slight back/forth vibration while the car is running around 36-38mph (in drive) and ~ 1500rpm (on a flat or slightly decline road). My car was more pronounced than this other one, but they both vibrate. The SM is convinced that it's the overdrive engagement and that speed and rpm is right at the point where it can slip and shudder between gears.

This issue cannot be replicated in manual mode at all or when you pop it into neutral at the same driving conditions.

Since they have already replaced the entire transmission, the SM manager is convinced this is normal activity and to not worry about impending failure of something in the drivetrain. He said to simply pop it into manual mode if I have to do driving in those conditions for an extended period of time.

I am concerned about this, but should I be?

What are your thoughts? Have you experienced this in your '06 (maybe '07 -'08?) M35x? If you were me what else would you do? Am I being a pushover or baby about this?

[Menace2Society]

yup i get the same thing in my 06 M35x. only difference is that the rattling of the steering wheel is more around 60mph... but nonetheless there is a problem. I've got 37K w/ new Michelin 245/45R18 aligned tiersthe dealership hasnt been much help either... and i haven't found a solution yet

[Shinobi326]

Thanks for the reply!

My biggest worry is the long term wear on something by letting is jitter around that mph and rpm. I've been trying to get used to popping it into manual drive (4th) when I have the longer stretches of posted 35mph road. However, I still feel like I shouldn't HAVE to do this as a workaround. I know I could simply drive it more aggressively instead of like a grandpa, but again, I don't think I should HAVE to do this.

I'm thinking of simply taking it to a different dealership to get them to evaluate it because its clear that the one I've been taking it to doesn't want to deal with it anymore.

[M45Runner]

However, I still feel like I shouldn't HAVE to do this as a workaround. I know I could simply drive it more aggressively instead of like a grandpa, but again, I don't think I should HAVE to do this.

I am not sure that is true. As the transmission is programmed to perform consistently and if your throttle combined with the speed of travel is forcing the transmission to shift (4th around 36mph and 5th around 38 mph), then, it will do exactly that. So, you would either need to change your driving habit (go either faster or slower) or override it (by using manual mode). It is a nice car, but it is still just a machine, you can not expect too much intelligent from it. Plus, that shows the transmission is very sensitive and respond to speed and throttle input very accurately.

[M45Runner]

I am concerned about this, but should I be?

What are your thoughts? Have you experienced this in your '06 (maybe '07 -'08?) M35x? If you were me what else would you do? Am I being a pushover or baby about this?

Yes, you should be concerned, since it will wear your transmission for sure.

If I were you, I would set the cruise control at 40-42mph and be done with it. So, based on that, you are definitely not a pushover.

[lovemycarM35]

Guys I'm replying to an old thread I have the exact same issue with my 2007 M35x and i'm out of warranty my car is stuttering around 37-38 MPH it's like a pulsating back and forth feeling but only at low speeds and very little throttle any other speed it's fine and if I give it just little more gas it goes away and it doesn't do it all the time. what I noticed is that my transmission is shifting smooth no banging in to gear or rough shifting. The transmission fluid has been flushed at 15K, 30K, 65K it now has 75k on it the fluid is also ruby red
no burn and full. There is a few threads out there with this issues my next step is to clean the throttle body. Any thought on this I can't afford the dealer right now maybe should go get an after market warranty any thoughts thanks


changed the plugs
replaced all 6 ignition coils
throttle body cleaning will be next

[svard75]

Careful with cleaning the TB. The process is to perform the cleaning without moving the butterfly otherwise you could get into a misalignment issue. I had to replace mine when I went nuts on it using the TB cleaner spray. If you really have to clean the inside then disconnect the TB connector and remove it from the plenum to clean both sides but be very careful to not move the butterfly.

[lovemycarM35]

Thanks man for the feed back I may just have the dealer do it I can't afford to break my TB I'm hopping someone throws me some more feed back the member who started this thread never posted back with the fix I do know the dealer replace the transmission and that didn't fix it Im nit sure what this is

[cruzad3r]

any carb cleaner for instance below is fine to clean the TB. There four bolts that you need to take off before you can remove the TB and once it's out, you can spray the cleaner directly to the butterfly valve. Do not touch it and let it air dry.