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og
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Discussion Starter #1
just replaced my carrier bearings hoping they might have been the cause (and they needed to be replaced anyway) but it has not fixed the problem. i experience it particularly in second and fourth gear, somewhat in third and fifth, not at all in first. it is a rotational vibration felt right around 3k rpms. it is felt more in the seat than anywhere else. starts faintly around 2500, gone by 3500. can also be felt particularly when car is under load at partial throttle. not speed dependent :mad:

had the car up on a lift, everything (axles, tie rods, driveshaft etc) seems solid. haven't checked motor mounts yet.

has anyone else had this problem? i am frustrated, any help is appreciated :)
 

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hey i'm in the same boat but i figured it was the carrier bearings. i haven't changed them because i don't drive the car much. i'll have to follow this to see what it could be. good luck
 

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No loer a Noob?
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You are describing my engin. It seems to run rough between 2500 and 3000 rpm. Seems to be when the engine gets to 3000 rpm or a little more it smooths out. Almost like the engine just vibrates at that rpm range.

Had done it since I got the car - have replaced tons of stuff and it still does it.

If I am cruising at 65 in 4th gear (around 2700-3000 rpm) I can feel a vibration. when I shift into 5th it is smooth - around 2500 rpm

sam
 

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og
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Discussion Starter #4
hrm, mebbe the problem will fix itself when i install my poly mounts. i doubt it however since the vibration is not felt in first gear at all. i expect it is something with the drivetrain, not the motor. driveshaft balance, axle problem, differential/transfer case/vcu, wheel hub/bearing something like that. cannot find it tho, hopefully someone else had the same prob and found the fix.
 

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yea thats how it is, but mine had never done it until i had my clutch replaced and tranny rebuilt, and then it did it. i thought maybe it was the way the tranny was installed or the shitty internals cuz it started grinding 2nd and 3rd 2 weeks after it was rebuilt.
 

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No loer a Noob?
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I have poly mounts now ;) - if anything it is worse now. (make me think engine)

replaced all idlers in the engine - clutch, throw out bearing, carrier bearings, U-joints.

sam
 

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og
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Discussion Starter #7
dammit i was hoping the polys would help, it doesn't sound like it. it originally seemed like changing the carrier bearings helped, but it did not. so now i'm stumped :mad: i'll be doing the 120k this week, but i don't expect much from that either :( new clutch (w/ tob) went in not too long ago as well. frustrated.
 

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og
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Discussion Starter #8
can anybody help us out here? i'm stumped.

i noticed yesterday on the drive home that the vibration is there even on deceleration, i.e. no throttle. as i decelerated through 3k rpms in second gear i felt the vibration, just coasting down to a stop no feet on any pedals.

i'm starting to get worried about it, as i think back i believe the vibration may be increasing, slowly but surely :(

any help or ideas? anybody have a similiar problem they fixed? i don't want to blow my shit up nor break something but i can't find anything wrong!. internal transmission or transfer case or rear or motor as sam mentioned? anyone?
 

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No loer a Noob?
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when you replaced the carrier bearings - how did the u-joints feel? I had a vibration at around 40mph that ended up being the u-joints. They where so stiff that would not bend.

sam
 

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rpm dependant- have you tried replacing your electrical stuff? coils, plug wires, grounds? i doubt grounds will help, but a lot of time, electrical stuff can help smooth out weird engine stuff. if it happens in any gear, then it's not drivetrain related... unless ur entire drivetrain is shot, which i doubt.

check ur timing yet?
 

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Mike, forgive me if I am WAY off base, but don't we have problems with harmonic balancers falling apart?

Just a thought.

Bob.
 

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og
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Discussion Starter #12
skunkworks said:
when you replaced the carrier bearings - how did the u-joints feel? I had a vibration at around 40mph that ended up being the u-joints. They where so stiff that would not bend.

sam
u joints were good. i checked them when i first dropped the driveshaft to change the carrier bearings.


Black_Sunshine said:
rpm dependant- have you tried replacing your electrical stuff? coils, plug wires, grounds? i doubt grounds will help, but a lot of time, electrical stuff can help smooth out weird engine stuff. if it happens in any gear, then it's not drivetrain related... unless ur entire drivetrain is shot, which i doubt.

check ur timing yet?
i just changed the plugs last week, did not change the wires but they are practically new, less than 10k on them. did not check the coils.

i have not checked my timing, i'll be doing so in a week or two, 120k coming up as soon as my hand heals :) i'll check coils at the same time.


OhioSpyderman said:
Mike, forgive me if I am WAY off base, but don't we have problems with harmonic balancers falling apart?

Just a thought.

Bob.
bob, i feel like slapping myself :p i'll be pulling my crank pulley when i do my 120k. i think you may be onto something there *crosses fingers*

thanks fellas :) i'll keep ya posted. has anyone else who's had this problem checked or changed their crank pulley?
 

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Sorry to dig that old post, but I've a VERY similar problem on my car:

no noise in first gear
noise/vibration from 2000 -> 2500 rpm and cycling noise at 3000+ (don't know exactly what rpm)

noise desapears when clutch is disengaged

noise is present whatever the load (strong accel, light load steady speed and slowing down)

So did you find out what was the problem on your car?

Thanks
ZB
 
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