Vibration

[tea18]

Gday guys,

I've got a '79 te72 t18 that is 100% stock. I have developed a severe vibration. I think its in the drivetrain as there is no vibration through the steering wheel. Another symptom is that it eases if I throttle on slightly, taking up freeplay I guess you could say. It also seems to get better and pretty much go away over about 40kph and its there regardless of being in or out of gear.

So I jumped under the car to check it out and the center bearing had a crapload of play in it. I have replaced that and it has made no difference to the vibration at all.

The gearbox, tailshaft and diff all seem to spin normally and everything 'looks' normal.

Any ideas as I'm lost as to where to look now?

Cheers

[Sam-Q]

tailshaft balance

[tea18]

This happened all of a sudden so wouldn't be suss on the tailshaft.

[Sam-Q]

the above point is a good one. I said tailshaft because one of the counterweights could of been knocked off with a rock or something. Admittedly I am don't know much about this subject

[ToddW]

When you replaced the centre bearing were the uni joints free and not binding?

[tea18]

The unis were fine from memory but worth having a look at.

[assassin10000]

There should be some slop/play in the center bearing mounting holes when the bolts are loose. Try and move it so the driveshaft looks almost inline from directly below.

Also check the pinion flange for play, bad pinion bearings could cause this too.

Andrew

[tea18]

I was thinking something with the pinion as the vibe goes through the whole car ie something connected to the body.

So pinion flange, just check the big nut is torqued correctly?

[assassin10000]

Not just that, check the flange itself for play up/down, left/right and in/out. As play like that is a sign of failed pinion bearings.

Although, now that I think about it more, you would also have horrible rear end noise if it was bad. So it's probably not.

Andrew

[Revan]

hmm never feel anything much through the steering wheel on the T18s courtesy of the steering box.... so don't rule out all the obvious/simple crap up front. good luck mate.

[tea18]

Not just that, check the flange itself for play up/down, left/right and in/out. As play like that is a sign of failed pinion bearings.

Although, now that I think about it more, you would also have horrible rear end noise if it was bad. So it's probably not.

Andrew

There is a horrible vibration noise but its hard to tell where its coming from while in the car, I'll check the flange.

[assassin10000]

Check all your wheel bearings, front & rear.

Andrew

[sundee]

Check weather the virbration continues while turning the car lock to lock, if their is a critical vibration occurring somewhere in the front end, this should take up that slop and stop the vibration as those parts will become "under load"
Dont be worried that it stops after 40km... do you have a bench grinder? when you turn them off, they have a point where a critical vibration point occurs.. but they still operate fine.
id be looking at tail shaft balance....
jack car up in all 4 corners and check wheel bearings\
also, jack car up and look at the front end, get someone to turn the wheel slightly and look for excessive movement in the balljoints etc

[Skylar]

Mate had a car with a bent tailshaft. Car shook like hell to 40k/h but cleared up after that. Worst was at 25k/h.

My only experience with bad wheel bearings is that they get worse with more speed.

[sundee]

Sorry, wrote the post before pretty quick, I guess the question to ask is , did the vibration occur suddenly or did it develop over a period of time?

[tea18]

Well, there has been a slight vibe when eng braking for years but nothing major. This one happened all of a sudden, I was trial braking through a roundabout and bam vibration.

[tea18]

So, I broke my finger and had to leave this for a while but back into again now.

Ive just check the front end and all looks as it should. Checked the pinion flange for play and it has no play in any direction, didn't pull the bearing as I would imagine there would be play if it was fingered.

Trying to check the rear wheel bearings but can't get the axles out, lol. The workshop manual says to use a slide hammer, which I don't own. I figured all you DIYers out there would have an alternative method you would like to share with me?

[tea18]

And i just noticed my rear uni only moves up and down and not side to side... Think I just found the issue. Would still like to do the rear bearings anyway i think.

[ThatsHowWeRoll]

uni joint doesn't have to move much to make a vibration. And can develop in a few days...the worse it gets the quicker it worsens..

[tea18]

This is like its seized.

[johl]

if you cant get your axles out just put on a stocko wheel backwards and smash the fuck out of it with a hammer

[tea18]

LOL, yeah I started to do that but pulling n the car started rocking on the axle stands... I'll get the hammer and the spare out.

[Vance]

a mate installed a dildo in your car as a prank?

[blinded]

Trying to check the rear wheel bearings but can't get the axles out, lol. The workshop manual says to use a slide hammer, which I don't own. I figured all you DIYers out there would have an alternative method you would like to share with me?

Not 100% sure, but have heard of people taking the drum off, flipping it and then putting the wheel nuts back on slightly. Then just grab hold of the drum and then that will act as a slide hammer when you slam it into the wheel nuts. something along those lines...

[tea18]

Arh, good idea! I like it, Thank you!!

[tea18]

So it turns out some bright spark at Toyota liked to use 'Staked uni's' the kind that i cant replace myself and alot of driveline joints wont replace either. They reckon to rebuild the tailshaft with the use of replaceable unis is going to be around 1g! The other option was to build a 1 piece for like 600. Im not keen on the single piece as Im worried it'll create some vibration of its own.

So options, 2nd hand tailshaft with the chance I'll be in the same boat again in the nearish future. Or spend a buttload on either a rebuilt 2 piece or custom single piece.

There is also the chance the car will get some kind of 'more modern' motor in the next couple of years, possibly needing another tailshaft anyway, which makes the idea of spending heaps not too attractive either.

Anyone got any thoughts on this? Or have an old tailshaft, lol? WTF I thought uni's arh not too much hassle then, WRONG!

[tea18]

So a custom tailshaft with holy massive unis has solved the issue.

At least I'll be able to make as power as I want and be OK.