Shudder at 40mph (~60km/h)
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Joined: Feb 2008
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Hey guys, definitely not a wheel balance issue. In fact, just to be sure, I had them rebalanced in the summer. From what I've read, and what my mechanical knowledge tells me, is that the torque converter is locking/unlocking at that speed range.
To answer your questions:
-Yes it's an auto, 5AT w/AWD (this problem is not with the AWD though).
-By shudder I mean holding the car at 40mph (60kmh) at a steady cruising speed (but not in cruise control)
-It feels as if the car is going over ripples on the road, slightly bucking forward and back really quickly, mossman said it best: it feels like you're in a manual car in 5th gear when you should be in 3rd, the car bucking and "shuddering"
-I attempted swapping over to DS (sport) when I feel shuddering, and it does not go away (unless the gear changes)
-It happens on level roads, and inclined roads. you definitely feel it more on inclined (uphill) roads. haven't noticed it going downhill.
-It's doing it at approximately 1500RPM
Wayne (gee35x): So this surging/bucking only happens when you're in cruise control?
So some of you guys are having this issue as well, you know what I'm talking about then, hopefully all our minds and efforts together will get this dealt with.
To answer your questions:
-Yes it's an auto, 5AT w/AWD (this problem is not with the AWD though).
-By shudder I mean holding the car at 40mph (60kmh) at a steady cruising speed (but not in cruise control)
-It feels as if the car is going over ripples on the road, slightly bucking forward and back really quickly, mossman said it best: it feels like you're in a manual car in 5th gear when you should be in 3rd, the car bucking and "shuddering"
-I attempted swapping over to DS (sport) when I feel shuddering, and it does not go away (unless the gear changes)
-It happens on level roads, and inclined roads. you definitely feel it more on inclined (uphill) roads. haven't noticed it going downhill.
-It's doing it at approximately 1500RPM
Wayne (gee35x): So this surging/bucking only happens when you're in cruise control?
So some of you guys are having this issue as well, you know what I'm talking about then, hopefully all our minds and efforts together will get this dealt with.
^+1 When I pick my friend up in the morning his driveway is pretty steep and it always happens then. He only lives 20 seconds away so at that point my engine is still cold as well. As others have also said, if I just give it a little more gas or let off the throttle and then back on it pretty much goes away.
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It may well be worth while for the tranny to relearn his driving habits with the possible change in tire diameter if that is the case.
Hey Johnnyzee, I am sooo sorry I am just responding to you. I totally forgot. My stealership included my valve assembly replacements under the TSB for the first generation. It is just a temporary fix, when my car is out of warranty I know this will still be an issue. But I've got documentation that this has been an issue since ownership.
My shuddering is never when using cruise control. It is only during mild acceleration all under 40mph. It is doing it again, so I'll be getting it replaced again probably before 50k. I don't bring it in for that until it starts doing it daily. If my service technician gives me any other info I'll definitely let you know.
My shuddering is never when using cruise control. It is only during mild acceleration all under 40mph. It is doing it again, so I'll be getting it replaced again probably before 50k. I don't bring it in for that until it starts doing it daily. If my service technician gives me any other info I'll definitely let you know.
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Ah, I had this issue when I installed my grounding kit, the car would lurch, studder and pick up. I let my car run with it for a few days after it didn't go away (went almost away to the point where i barely feel it) I just disconnected the battery and reattached it and it fixed it for me. If it's still happening on your car I dunno.
Sounds like we have the same exact issue. It does it when I am not using cruise control. It does go away when I go into DS mode but I thought it always down shifted at 40 going from D to DS. Maybe it was just because I switched into DS going up a small hill. Whenever I give it more gas to force a downshift it stops right away. I have a small hill when I leave work so I experience this just about every single day. It's slightly worse if the engine is cold, but it's always there.
(sucks to be us)!
Originally Posted by leffizet
^+1 When I pick my friend up in the morning his driveway is pretty steep and it always happens then. He only lives 20 seconds away so at that point my engine is still cold as well. As others have also said, if I just give it a little more gas or let off the throttle and then back on it pretty much goes away.
Originally Posted by pfarmer
While he doesn't state as far as I can tell that he is in cruise control, I have to mention that on my 08 that the cruise control actually does cause a lot of speed variation going up and down hills compared to the other cars I have had. Locking in a lower gear helps a little bit. I have an 08 XS. What I am wondering is that he does have 19s but doesn't state what size 19s.
It may well be worth while for the tranny to relearn his driving habits with the possible change in tire diameter if that is the case.
It may well be worth while for the tranny to relearn his driving habits with the possible change in tire diameter if that is the case.
It's happening in regular drive, not cruise control. Nothing to do with the 19's. It does the same thing with the stock 17's, I tried that. I rebalanced both sets, no fix. I re-aligned the wheels, no fix. Reset CPU (unplug battery overnight), no fix. It's been doing this for a long while now.
Originally Posted by baileyt35
Hey Johnnyzee, I am sooo sorry I am just responding to you. I totally forgot. My stealership included my valve assembly replacements under the TSB for the first generation. It is just a temporary fix, when my car is out of warranty I know this will still be an issue. But I've got documentation that this has been an issue since ownership.
My shuddering is never when using cruise control. It is only during mild acceleration all under 40mph. It is doing it again, so I'll be getting it replaced again probably before 50k. I don't bring it in for that until it starts doing it daily. If my service technician gives me any other info I'll definitely let you know.
My shuddering is never when using cruise control. It is only during mild acceleration all under 40mph. It is doing it again, so I'll be getting it replaced again probably before 50k. I don't bring it in for that until it starts doing it daily. If my service technician gives me any other info I'll definitely let you know.
No worries, thanks for chippin' in the discussion here.
OK, so you got the valve assembly replaced using the TSB from a 1st gen G35. I wish I could go to your dealership (road trip, hahaha). Does this fix the problem?
Is there anything else they did or just change the valve assembly? How long does it hold up?
Originally Posted by dghboybigboy
Ah, I had this issue when I installed my grounding kit, the car would lurch, studder and pick up. I let my car run with it for a few days after it didn't go away (went almost away to the point where i barely feel it) I just disconnected the battery and reattached it and it fixed it for me. If it's still happening on your car I dunno.
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From: M.E.M.P.H.I.S/Smyrna, TN
I get this same issue when my car is around 2K RPM, it's a hard vibration like my rear wheels are going to fall off, and of course I notice it more when going up an incline! WTF????
^ you rock!
thanks for that research...
I'm personally not a believer in the "throttle sensitivity ITB" as I have an 08 and I should have this newer flash applied to my model year. I don't see the ECM flash being the culprit.
From what I'm gathering in your posted info, is the problem occurs in this half-clutched state. Someone chime in if i'm wrong here but it appears to me that the problem could be:
- TCM giving improper output to clutch solenoid. (needs reflash???)
or
- Torque convertor clutch / solenoid / piston malfunction (how do you prove/diagnose that???)
TREACHEROUS:
Are you going to address this issue with them when you go in to the dealer? If so, let us know what you can find out. (I'll be ever so patiently waiting)hahaha-this is driving me nuts.
thanks for that research...
I'm personally not a believer in the "throttle sensitivity ITB" as I have an 08 and I should have this newer flash applied to my model year. I don't see the ECM flash being the culprit.
From what I'm gathering in your posted info, is the problem occurs in this half-clutched state. Someone chime in if i'm wrong here but it appears to me that the problem could be:
- TCM giving improper output to clutch solenoid. (needs reflash???)
or
- Torque convertor clutch / solenoid / piston malfunction (how do you prove/diagnose that???)
TREACHEROUS:
Are you going to address this issue with them when you go in to the dealer? If so, let us know what you can find out. (I'll be ever so patiently waiting)hahaha-this is driving me nuts.
Trreacherous: I'm happy those cookies and mocha got the better of you! I seriously hope that this flash takes care of it.
I purchased my G in the beginning of January 2008. It was a new years resolution to treat myself a little...hahaha. It's been a great ride so far except for this shuddering issue...which, as you've noticed, is seriously driving me nuts. I am really crossing my fingers on this for both our sakes.
I definitely think you're onto something with the build dates of the G. My car WAS built sometime in 2007, as it was on the lot before new years day. I may very well have an older version flash. You got me very excited here,there is some hope for me to fix this. I'm also crossing my fingers that this TSB applies to me as well (THANK YOU for getting those ITB and flash version numbers for me by the way...very helpful).
I'm also with you, I didn't buy the G for its gas mileage, not a concern for me either. I just want the thing to be smooth, that's all I ask.
I'll wait a few weeks to see how your flash is holding up before I run in to the dealer. Keep us updated.
Thanks for the awesome help!
I purchased my G in the beginning of January 2008. It was a new years resolution to treat myself a little...hahaha. It's been a great ride so far except for this shuddering issue...which, as you've noticed, is seriously driving me nuts. I am really crossing my fingers on this for both our sakes.
I definitely think you're onto something with the build dates of the G. My car WAS built sometime in 2007, as it was on the lot before new years day. I may very well have an older version flash. You got me very excited here,there is some hope for me to fix this. I'm also crossing my fingers that this TSB applies to me as well (THANK YOU for getting those ITB and flash version numbers for me by the way...very helpful).
I'm also with you, I didn't buy the G for its gas mileage, not a concern for me either. I just want the thing to be smooth, that's all I ask.
I'll wait a few weeks to see how your flash is holding up before I run in to the dealer. Keep us updated.
Thanks for the awesome help!
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Joined: Sep 2009
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If I remember correctly there is a magic number mph for torque converter lockup, something like 28 or so if one is maintaining speed in that area.
^ That's great that you have 2 test drivers (you and the mrs.) working on if it has been fixed or not.
Let's hope it doesn't get to the valve body or TC replacement, (crossing my fingers).
On that note...
The people in here having this same issue...have any of you had your ECM reflashed and still have this problem?
Let's hope it doesn't get to the valve body or TC replacement, (crossing my fingers).
On that note...
The people in here having this same issue...have any of you had your ECM reflashed and still have this problem?