Tailshaft or something else??

[Tom86]

Hi everyone,

A quick question for people that have out of balance tailshaft or stuffed uni joint before. What kind of noise or symptom does the car exhibit when you have bad tailshaft? Because lately my car start to make humming kinda noise and vibration at certain speed and it is more evident when hot (ie after 20min drive). I can definitely feel distinct vibration when the engine @ 3100-3500rpm through the cabin and gear stick. If i put my foot down and rev pass the 3-4k range its not so bad, but when I have to just cruise along at freeway speed in 4th or 5th you can definately feel it.

Does this sound like a tailshaft issue or could it be something else?

Thank you

[BeRad]

It could be many things from as basic to needing a wheel allignment to, rebalancing the tailshaft, new uni's etc, rooted uni's ussualy make a clunk/ting noise when you back off the accelerator.

[fatboy13]

i had the same thing happening with my car... ended up being the bearing in the middle of my tailshaft.... (2 piece) it was stuffed and at certain revs and in certain gears you could feel it.

[Vios-GT_07]

why don't you try checking and replacing the uni joints first, and balancing the tailshaft?

a vibration can be caused by anything really... apart from wheel alignment, can also be clutch or flywheel, a buckled wheel, wheel bearings need attention etc etc..

do what i always do, make a list and go through it one by one

edit : if it's specific to a rev, could also be an engine thing so spark plugs, leads, dizzy / coils, fuel filter.. or maybe something's loose undercarriage?

[Tom86]

I suspect that it could be the tailshaft, but just want to check before I pull it out and spend the money. The last quote for replacing uni-joints was almost $500. Damn everything is falling apart on me .

[Black]

$500 for uni joints....... thats gotta be wrong!!

[BeRad]

haha they saw you coming, unis are nice and easy to replace and cheap also... buy a repair manual if you dont know how and give it a go yourself.

[Rodger]

It is unlikely that the tailshaft will suddenly go out of balance. The weights Toyota put on to balance them are usually spot welded on. Uni joints wear so any sound would slowly increase as they wear out and if they fail they really fail and go clunk and usually fall out.

If it is a two piece as said before check the centre bearing support as the rubber mount could have failed.

Try and avoid suspecting the uni joints, they can be notchy when moving them by hand and still be ok and safe to use. They also can get dirt in the bearings and this can be cleaned to free them up a bit.

If the sound is speed specific, changes as load and speed change and is not related to certain gears, I would say diff.
It can come on rather quickly especially if you have given it a good hard run such as a trip down the strip or done a track day. Wearing crown and pinion gears can be very loud and loadest at around 80 - 100km/h. This can be felt and heard in the cabin as a vibration and sound. Hot oil is thinner, so there is less cushioning the gears which makes it louder.

Regards

Rodger

[Tom86]

haha they saw you coming, unis are nice and easy to replace and cheap also... buy a repair manual if you dont know how and give it a go yourself.

I was told that they're non-replacable type (from a Sprinter) and the guy at the shop was going to cut them out and replace them with one from a Ford or Holden??

The tailshaft that is in the car at the moment has never been balance it was piece together from two different car the front half from one car and the other half from other car. I wasn't perfect to start with so I think that is partly to blame.

If it is a two piece as said before check the centre bearing support as the rubber mount could have failed.

Will definately check the centre bearing. The vibration is somewhere in the vacinity of the centre bearing so that could be it.

[The Real Roadrunner]

probably the centre bearing as said before.
some toyotas are non replaceable so that is true.
check c/bearing and replace if worn, balance the shaft when it all goes together as this may be the reason it went bad in the first place.
cheers
linden