Good Vibrations!

[Terminal]

I drove from Bathurst to Sydney this morning, and after a while I started to notice (hear and feel) a vibration resonating from what I'm pretty sure is the gearbox area. I tried accelerating in a few different gears past 80km/h and the shudder was the same for all, so I determined it isn't a gearbox problem. the engine still revs fine up to 7000rpm so it's not an engine problem. the shudders aren't coming through the steering wheel as such, more the entire car is shuddering, so it's not a steering alignment/balance problem. It picks up a resonance of around 1-2Hz as I'm driving over 80km/h, but it comes and goes, usually for about half an hour at a time. The vibrations are constant however.

My theory is either a Uni-joint on the tail shaft, or a bearing somewhere in the gearbox/tailshaft region. I'm not an expert on the mechanics down there so it's just speculation.

My question now is has anyone experienced a uni-joint or tail shaft problem before? this is a first for me as neither of my previous cars have had the problem. If I'm right and it's a uni-joint, how hard/expensive are they to replace? I'm trying to sell the car, I don't need an expensive repair job right now.

If anyone has some guidance for me let me know, otherwise i'll have to see a transmission mechanic to help me out.

Cheers,

Leshy

[RubyRS4]

It does sound like a uni joint.

I've had one fail ever so slightly and it is definitely felt in the body of the car. Fixing them is simple enough if you wanna give it a go yourself.

Remove the circlip and use a flat head screw driver and hammer to tap them out. A suitable mechanic should be able to replace them cheap enough.

Also, if your tailshaft is out of balance, this will cause the problem also. But the weights to balance it are usually welded on, so its rare.

Edited April 9, 2008 by RubyRS4

[Stinky Rooster]

Not good dude! It might be a uni, but in my experience if the uni is failing there is usually a tapping or knocking sound associated with the vibration due to the bearing surfaces in the uni constantly coming in and out of contact with each other. I know tailshaft balance problems are rare, but I would be looking closely at the rear tailshaft anyway to make sure there are no shiny patches where weights may have dropped off.

Yours is a manual, isn't it? How was the clutch surface of your flywheel when it was installed?, but you will know if this is the problem because the clutch will start to slip.

Also have a close look at your wheels (esp the front ones) to make sure there is no balancing weights that have gone south.

Other than that, all I can think of is the dreaded ATESSA system problems (maybe chain drive to the transfer case?)

[Terminal]

yeah i don't think it's out of balance, hopefully just a uni joint. are they skyline / stagea specific, or just a generic uni joint off the shelf? I'll have a look when I get home on the weekend, see if there's much movement in the joints.

I've already blown one transfer case apart, i don't want to do it again. it's making very differnet noises to the time my transfer case kicked the bucket, so that's why i didn't think that initially. I had the flywheel machined flat when I had it all installed. The vibrations are intermitted, so perhaps it's only just starting to fail? theres a lot of vibration in the gearstick too.

[Stinky Rooster]

Are you sure there is no noise? Cause when the uni in my front drive shaft went, the clacking noise drove me nearly batshit crazy.

[RubyRS4]

Are you sure there is no noise? Cause when the uni in my front drive shaft went, the clacking noise drove me nearly batshit crazy.

The uni joint can fail ever so slightly that the tailshaft is slightly out of alignment horizontally, making it out of balance. Whereby you feel the vibrations, but no noise might be assoicated with it as the joint spins up with centrifigal forces. A bit like sitting in the Gravitron!

[Terminal]

yeah well it gets worse with speed rather than RPM, which ruled out the clutch. I know I need new front tyres and a wheel alignment/balance, but it shouldn't be vibrating the whole car. also the noise is coming from the gearstick hole. i'm glad i didn't seal the hole completely, else I might not have heard it at all.

I'd hate to go batshit crazy, i'll fix it asap!

[Terminal]

Well my problem answered itself. I'm currently stuck on the side of the M4 near the cumberland highway with a front driveshaft hanging out of my car. cruising along at 90k's something suddenly went BANG then i lost my clutch and the engine died. the driveshaft was hanging off the front of the car like a rag doll.... this is the 2nd time my gearbox has kerploded on me, i don't know what i'm doing wrong, i had professional gearbox mechanics install it after it broke the first time.

anywho, i'll just become a resident of the M4 for the next hour or so until NRMA comes to pick me up I guess.... doh

it has to happen when I'm trying to sell the car doesn't it.

[ssshonky]

sh1t dude ! bad news ! I was hoping to get on here and say" check the tyres for bubbles " and you would be like ZOMG thats it - and I would be like - huzzah - hooray for boobies- and that sort of cary on .

maybe your gearbox / transfer case mounts are stuffed?

[DaveB]

Well my problem answered itself. I'm currently stuck on the side of the M4 near the cumberland highway with a front driveshaft hanging out of my car. cruising along at 90k's something suddenly went BANG then i lost my clutch and the engine died. the driveshaft was hanging off the front of the car like a rag doll.... this is the 2nd time my gearbox has kerploded on me, i don't know what i'm doing wrong, i had professional gearbox mechanics install it after it broke the first time.

anywho, i'll just become a resident of the M4 for the next hour or so until NRMA comes to pick me up I guess.... doh

it has to happen when I'm trying to sell the car doesn't it.

Damn, that sucks but at least you've found the problem big that can be the worst part, not being able to find what the problem is...

lol you've got no car, you're stuck on the side of the M4, and you're still posting?

Edited April 10, 2008 by DaveB

[Terminal]

well when i initially put my gearbox in, the transfer case destroyed itself within a month. I got the whole thing replaced properly and now this happens after 6 months. I'll be talking to the workshop in question about a warranty on this, because there's no way I'm that unlucky to buy 2 lemon transfer cases

[RubyRS4]

Oh man that sucks the big one!

If its your driveshaft that blew, how recently was your gearbox fixed the first time? Try hitting up the mechanics for a repair. Was it bearing failure? Check the docket/invoice from you previous work to see what was involved. It might be covered.

Sorry, the only assistance I can give seeing I'm in Adelaide and you're on the side of the M4.

Added: can you get pics of the damage/break? Post 'em up

Edited April 10, 2008 by RubyRS4

[Terminal]

Damn, that sucks but at least you've found the problem big that can be the worst part, not being able to find what the problem is...

lol you've got no car, you're stuck on the side of the M4, and you're still posting?

Wireless Baby! I've got my work laptop with me and a NextG card

[Terminal]

Here's the damage I can see

[Stinky Rooster]

Is that the front or rear driveshaft? And why have you lost the clutch?

[Terminal]

Great, the tow truck they brought out can't tow AWD's... yay NRMA

[RubyRS4]

Great, the tow truck they brought out can't tow AWD's... yay NRMA

Its not AWD right at this moment

[Terminal]

That's the front. I don't know why I lost the clutch, but she's flat to the floor

[Stinky Rooster]

Um...maybe because the front shaft has taken out your clutch actuator

When mine went, the uni had punched the bearing retainer almost al the way through, I was about 5km of driving away from what happened to you....

[Terminal]

yeah luckily i have a spare slave cylinder at home, but the rest might be a problem, what do transfer cases go for these days?