'03 M45 Clunk/Slip -- Any Ideas?

[M45Caliber]

OK -- while I wait 15 more days for the Elite Warranty grace period to end, something new has just cropped up over the past few days.

When shifting from reverse to drive (car is stopped and not rolling when I do this...) I occasionally get a loud CLUNK sound and it almost feels as if the wheels spun for 1/4 turn on some oil or water - which it hasn't, because I stopped and went back and looked at the road.

Once again, this puppy now has 38K on it, and I had the rear diff fluid changed out by the Infiniti dealer about 3K miles ago.

If this thing had a LSD, I'd say it was the clutch pack going out or grabbing... but my uderstanding is that's not the case on these cars.

Any ideas or suggestions. It's very un-nerving when it happens. Once I am in drive I hear nothing out of the ordinary, even under full-throttle acceleration.

[Double E]

Lift it and crawl under there and wiggle the universal joint (it has one right?) for excessive play. Based on the description, that's where I'd look first.

Check transmission fluid for unusual level or smell/texture.

I have 62K on mine with no similar issues.

[szh]

Definitely check the transmission fluid level!! You do NOT want the transmission to die too soon. An expensive replacement ...

Z

[M4T5]

At best your looking at either: -a bad motor mount (this is easily checked with parking brake on and someone shifting from R to D and vice versa. Look for excessive engine shifting upwards on one side. Though you hardly have the miles on it for that, but it may have enough age on them)

-Bad U-joint (not sure if it has a U-joint...maybe they use a C.V. type joint there instead.) If so, that could be worn or wearing out.

-or worn/ failing internal part in differential.

I hope for your sake it is one those three items. That would be horrible if it is the transmission......

if your M is still under warranty as you are saying it is..... TAKE IT IN NOW!....well tomorrow MORNING! If you still have a grace period remaining, I would quit trying to figure it out and get it in the dealer ASAP. Let us know what you or they find causing this.

J

[M45Caliber]

I will check the transmission fluid tomorrow. Only 38K miles and transmission has been drained/refilled twice; most recently 3K miles ago when they also did the diff. I can not imagine in 38K miles that the transmission is going south. The sound is emminating from the rear of the car, which had me suspecting the diff or u-joint. It's a strange noise/sensation and it's intermitent in that is doesn't do it all the time.

I notice it mainly when I am backing up while turning (like out of my driveway onto the street). Now that I think about it, I am always hearing it when backing up and turing the steering wheel counter-clockwise (example -- car facing north and backing up (south) and turning the wheel so that the front of the car is pointing east - if that makes sense). I stop and drop it from "R" into "D", and touch the gas -- I hear that "Clunk" or "grunch" type of sound and it feels like the wheels slip for a mili-second, then off I go and never hear it again until I do the back up/turn scenario. But NOT all the time -- maybe once outta 4 times do I hear/feel it.I will play around with it some tomorrow and see if I can replicate consistantly. I hate to do too much as the Elite Warr doesn't kick in for 12 more days! Yikes.

If it were a U-joint or transmission issue, I should hear it/feel it all the time - or at least when starting out from a stop, for instance.

I have this strange feeling that perhaps the tech that drained/refilled my diff a few months back might not have filled it completely? I will check that out tomorrow as well.

[M4T5]

You need to raise the car and check all suspension parts with force. Look for any unusual components that shift or have play in them. I almost don't want to say a suspension part, but you never know. I thought your Elite service plan was ending.... didn't know it was about to start.Being it doesn't do it all of the time might be something they will not spend much time diagnosing until problem gets worse and more consistent. If you can get the noise to replicate all of the time, then you can show the tech personally what it is doing.

J

[striz923]

I have heard you most recent description described a couple of times on the forum here. search back for the past few months and see if you can dig it up.

[M45Caliber]

OK -- I have a good friend who is an ASE Certified master mechanic and he owns his own independent repair shop in Mesa, AZ. I've used him for years on our "Kid Cars" -- i.e. cars out of warranty and being driven by our kids. He's honest and he's a great mechanic (heck man, he works on Land Rovers and Jaguars when the Scottsdale dealership can't figure out whats wrong... so he's almost a magician - LOL).Anyhow I drove over to his shop and we put it up on the Hunter alignment rack so we could poke around. Diff fluid started coming out before we had the refill (upper plug on the side of the diff) plug out all the way - a nice clear/pale amber color (just a few dribbles so the plug went back in). So we closed that up. Checked all the struts/shocks, checked the driveshaft and various Ujoints - solid. Double-checked all the suspension bolts as he performed the 4-wheel alignment a month earlier ( newest Hunter rack = like watching a laser light show - cool stuff). Checked the wheels and everything seemed bolted down OK. So, Everything underneath solid. Keep in mind that this car was a garaged California car - in MILD semi-arid climate it's whole life, so ALL of the rubber components look new. Amazing - at 38K miles and you could eat off the undercarrage - NO grime or dirt what so ever. Everthing clean and easy to look at, grasp, and "shake" or try and move around.

Dropped the car and fired it up and checked the motor mounts - nadda. That monster motor doesn't move when torqued in gear. Checked the trans fluid level (that was fun -- never knew there was a 10mm bolt holding the transmission fluid dip stick down - must be some serious pressure in there!) Anyhow, the fluid was clear and full - between the two holes on the stick where the word "HOT" is stamped between them - actually touching the top hole but NOT into the hashed marks on the stick above the holes. I did the sniff test and all I smelled was transmission fluid -- nothing even remotely burnt.

QUESTION: What color is the Nissan ATF? This looked almost clear on the dipstick and no color to speak of when wiped on a towel.

So, now I am at a complete loss. I will continue to drive this until I can replicate the issue for the mechanics OR it just goes away. Any other thoughts appreciated -- thanks again guys.

[Tekmazter]

Hey M45 Caliber. I have an '03 M45 with about 72K on it now. I have had this happen to me randomly since I purchased the vehicle with 48K on it. It's completely random and has never given me any issues other than the odd noise and feel.

I do not know what the issue is. However, I can tell you from my personal experience that it has not gotten worse and has happened in total maybe 5-6 times in 2 years. It's become one of those things where I try and remember to have the dealer take a look at it, but always forget. It just isn't something that happens frequently enough for me to care about.

Some notes:

I drive this car in the Northeast where the seasons can wreak havoc on most vehicles, yet I have not seen this issue get worse. I regularly have the oil changed (synthetic) and maintain fluid levels at regular checks. I occasionally drive this vehicle hard (get on it on the highway in and out of lanes) but have not seen this issue become more frequent. The vehicle is under warranty so I do not overly worry due to the frequency at which I experience what you have described.

Let me know if you get a definitive answer as to what causes this ... I'm more curious at this point unless you find out our cars are doomed

[M4T5]

Since there are no found external mechanical worn parts or loose bolts to be found, this is really starting to sound like an internal issue in the transmission. Sounds like a sensor pertaining to the traction control system. Is it possible that this is just a self initial test of the system? It's possible that it is just noticed sometimes and specific moments that the car is placed from R to D. Have you pin pointed it down to doing this only when the car is switched from R then to D? If so, then it has to be in the transmission. This is not saying there is something wrong with it either. Is it possible that there could be a transmission code that has triggered that does not trigger the check engine light? You should check further into this. Some code scanners only have the ability to check for engine codes, but not transmission, ABS, or air bag codes. Just an FYI..Good luck on figuring this out. I too would like to know the end result if any.

J