Howdy,
I have a nagging vibration that goes through the car at 100k's plus. The faster I go, the worse it gets. It has a sort of rhythm to it which in words would be like "wirrrr, wirrrr, wirrrr, wirrrr" (one second per wirrrr"). I cant quite work out where it is coming from but as the shifter doesnt seem to vibrate I suspect it is the from the tailshft back.
I thought having no rubber grommets where the transmission crossmember bolts to the chassis might be the reason but after putting the grommets in nothing has changed.
I am wondering if perhaps it is the pinion angle (after reading about that on here and in a recent street machine).
I can have a go at fixing it myself but was wondering what sort of business would be the best to take the car to if its beyond my tools and ability? Suspension shop? Mechanics? etc
Car is 308 UC with trimatic and 9 inch. 14 inch wheels all round and it has been lowered a little bit.
Any help with trying to find the problem or a recomendation of someone who can would be great.
Cheers,
Tony
Vibration at 100km/h+ ? Possible causes?
Started by
_Big T_
, Sep 04 2010 05:38 PM
25 replies to this topic
#2
_mumstaxi_
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Posted 04 September 2010 - 05:48 PM
Can you drive through it tone, as in does it go away if you keep going faster 110+ etc, also is it only under load,does it go away if you back off and coast at 100ks ?
First thing id check is your uni joints tho
MT
First thing id check is your uni joints tho
MT
#3
_Quagmire_
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Posted 04 September 2010 - 06:12 PM
wheel bearings unis loose wheel nuts wheel alinment bent rim/rims
suspension bits worn
any number of things
i'd do you unis then take it to a compdent suspenison place (ie not pedders,although you could do there $14 saftey check and not get them to do the work)
but yeah could be a meriad of other things to
does it get worse when braking?
suspension bits worn
any number of things
i'd do you unis then take it to a compdent suspenison place (ie not pedders,although you could do there $14 saftey check and not get them to do the work)
but yeah could be a meriad of other things to
does it get worse when braking?
#4
fuzzypumper
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Posted 04 September 2010 - 06:35 PM
One a second suggests a resonance vibration.
I've had a similar resonance vibration for years at 100-110 kph and higher.
Its a 253, trimatic, banjo and I have changed, the unis, diff centre, wheel bearings,
torque converter, axles checked, new exhaust(but its noisier one), different rear rims and tyres.
None of which has made any real difference.
Off course 100kph in top gear means about 2900rpm for me and equates to the camshaft just coming into
action so extra engine stress come into play.
Im now thinking it may be the trimatic or engine balance.
I did change engine oil recently which sorta changed the intensity of vibration.
Maybe try it second gear at the same revs the vibrations show up in third gear.
Or coast down a long hill at 100kph out of gear idling?
Good luck.
I've had a similar resonance vibration for years at 100-110 kph and higher.
Its a 253, trimatic, banjo and I have changed, the unis, diff centre, wheel bearings,
torque converter, axles checked, new exhaust(but its noisier one), different rear rims and tyres.
None of which has made any real difference.
Off course 100kph in top gear means about 2900rpm for me and equates to the camshaft just coming into
action so extra engine stress come into play.
Im now thinking it may be the trimatic or engine balance.
I did change engine oil recently which sorta changed the intensity of vibration.
Maybe try it second gear at the same revs the vibrations show up in third gear.
Or coast down a long hill at 100kph out of gear idling?
Good luck.
#5
GML-31
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Posted 04 September 2010 - 08:29 PM
Tony make sure your uni is seated properly after you put your diff back in
#6
S pack
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Posted 04 September 2010 - 08:38 PM
Hi Tony
I gather from what you're saying the vibration is road speed dependent not engine speed.
If it was only a noise I would say it is wheel bearings but seeing as it's a vibration I would be looking at the uni joints first.
get under the car, grab the tailshaft at each end and see if there is any movement in the uni's.
Had the same sort of vibration in my LJ and when I pulled the uni joints out some of the needle rollers had vanished into powder.
Cheers
Dave.
I gather from what you're saying the vibration is road speed dependent not engine speed.
If it was only a noise I would say it is wheel bearings but seeing as it's a vibration I would be looking at the uni joints first.
get under the car, grab the tailshaft at each end and see if there is any movement in the uni's.
Had the same sort of vibration in my LJ and when I pulled the uni joints out some of the needle rollers had vanished into powder.
Cheers
Dave.
#7
FastEHHolden
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Posted 04 September 2010 - 08:58 PM
Apart from uni condition and correct seating of the rear uni....Check the phasing of the uni's....are they directly in line front to back?
#8
_tail light_
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Posted 04 September 2010 - 10:02 PM
good point fasteh, the yoke on the tail shaft need to be the same position welded in front to back, especially this tail shaft drive line combo may of required the shaft to bet cut,
the shaft trungens need to be the same poistion front uni to back uni, for the uni to work correctly
the shaft trungens need to be the same poistion front uni to back uni, for the uni to work correctly
#9
surfmaster
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Posted 04 September 2010 - 10:33 PM
Uni joints or maybe rear transmission mount stuffed, or rear wheel balance.
#10
GML-31
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Posted 04 September 2010 - 10:43 PM
hes just had his diff done I think so my money is on the uni
#11
ls2lxhatch
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Posted 05 September 2010 - 01:45 AM
It sounds the the sort of vibration you will get if the pinion and gearbox angles are not cancelled. A diff conversion or even just altering the ride height can put the pinion angle out.
This article explains what you are trying to achieve and how to measure the angles.
This article explains what you are trying to achieve and how to measure the angles.
#12
_Big T_
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Posted 05 September 2010 - 09:15 AM
Thanks heaps for the replies so far. Looks like Uni joints are the first thing I need to check !!
To answer a couple of questions:
After accelerating to 110 and taking my foot off the fast pedal the vibration is still there until my speed drops back to under 100. The vibration doesnt go away if I go any faster than 100, in fact, it gets worse.
Braking doesnt seem to make a difference.
I had 15 inch wheels and the vibration was there at the same point. I changed to 14 inch wheels with no difference. Not sure if this change in ride height would be enough to eliminate a pinion angle problem or not? It does however suggest the wheels are not the problem (bent or out of shape rims).
From what I can gather the vibration is road speed related however I will test today (if I get the chance) and see if it happens at the same revs in 2nd as it does in 3rd (probably about 3500-4000 rpm). First of all I will crawl under the car and check for any play in the uni's.
Cool, I just got a model Antelope SLR5000 for Father Day !! Thanks Wesley
Ok, back to it.
Im not sure I understand the "phasing" Fasteh refers to?
Kev, the diff didnt end up getting done unfortunately. I was hoping it would have been done yesterday however I didnt pan out.
Rear transmission mount. Are these the two bolts where the trans mounts to the crossmember?
Looks like I have some reading to do on pinion angles as well.
Thanks guys, the help is really appreciated.
Have a Happy Fathers Day
Cheers,
Tony
To answer a couple of questions:
After accelerating to 110 and taking my foot off the fast pedal the vibration is still there until my speed drops back to under 100. The vibration doesnt go away if I go any faster than 100, in fact, it gets worse.
Braking doesnt seem to make a difference.
I had 15 inch wheels and the vibration was there at the same point. I changed to 14 inch wheels with no difference. Not sure if this change in ride height would be enough to eliminate a pinion angle problem or not? It does however suggest the wheels are not the problem (bent or out of shape rims).
From what I can gather the vibration is road speed related however I will test today (if I get the chance) and see if it happens at the same revs in 2nd as it does in 3rd (probably about 3500-4000 rpm). First of all I will crawl under the car and check for any play in the uni's.
Cool, I just got a model Antelope SLR5000 for Father Day !! Thanks Wesley
Ok, back to it.
Im not sure I understand the "phasing" Fasteh refers to?
Kev, the diff didnt end up getting done unfortunately. I was hoping it would have been done yesterday however I didnt pan out.
Rear transmission mount. Are these the two bolts where the trans mounts to the crossmember?
Looks like I have some reading to do on pinion angles as well.
Thanks guys, the help is really appreciated.
Have a Happy Fathers Day
Cheers,
Tony
#13
_Woodsy_
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Posted 05 September 2010 - 09:35 AM
I had a similar problem in my Hatchback but if i went faster it would go away, never found out what it was though.
#14
_Yella SLuR_
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Posted 05 September 2010 - 10:02 AM
Sure it's not the engine just running through it's normal firing sequence? Sounds like it. Is it just a whirring noise, not necessarily a vibration? Sounds pretty normal to me.
#15
ls2lxhatch
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Posted 05 September 2010 - 12:03 PM
If it is pinion angle related then the vibration should occur at the same rpm in top gear (tailshaft rpm) regardless of the actual road speed.
In terms of ride height it is suspension ride height not actual ride height. The pinion angle on a Torana will change during suspension travel. You may find that putting some weight in the boot is enough to alter the pinion angle and change the tailshaft rpm where the vibration starts. A spacer under the gearbox will also alter the angles. If either of these change the tailshaft rpm of the vibration then it would indicate that uncancelled angles are the cause.
Phasing refers to the relationship between the two unis on the tailshaft, both unis should be on the same angle. A one piece tailshaft built properly should not have phasing issues as the uni angle can not be changed. It would still be worth checking it was made properly. Phasing is more likely to be an issue with splined tail shafts that can be pulled apart and carelessly reassembled with the unis on different angles.
In terms of ride height it is suspension ride height not actual ride height. The pinion angle on a Torana will change during suspension travel. You may find that putting some weight in the boot is enough to alter the pinion angle and change the tailshaft rpm where the vibration starts. A spacer under the gearbox will also alter the angles. If either of these change the tailshaft rpm of the vibration then it would indicate that uncancelled angles are the cause.
Phasing refers to the relationship between the two unis on the tailshaft, both unis should be on the same angle. A one piece tailshaft built properly should not have phasing issues as the uni angle can not be changed. It would still be worth checking it was made properly. Phasing is more likely to be an issue with splined tail shafts that can be pulled apart and carelessly reassembled with the unis on different angles.
#16
_Big T_
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Posted 05 September 2010 - 04:04 PM
Thanks for the info on pinion angle and phasing Andy, very helpful.
I took the tailshaft out and my bro in law is dropping it off to get balanced and new uni's. There was a little bit of play in the rear uni and when we took the caps off it the little bearing things were crushed and buggered.
The tailshaft D bolts are also looking worse for wear so I need new ones. Anyone know where to get them? Neither autobarns nor repco stock them or know where to get them?!?!?! I wouldnt have thought they were that special. Anyway I will hit Mr Google for an answer but Im guessing someone like The Bolt Bloke would have them.
I will let you all know how it goes.
Cheers,
T
I took the tailshaft out and my bro in law is dropping it off to get balanced and new uni's. There was a little bit of play in the rear uni and when we took the caps off it the little bearing things were crushed and buggered.
The tailshaft D bolts are also looking worse for wear so I need new ones. Anyone know where to get them? Neither autobarns nor repco stock them or know where to get them?!?!?! I wouldnt have thought they were that special. Anyway I will hit Mr Google for an answer but Im guessing someone like The Bolt Bloke would have them.
I will let you all know how it goes.
Cheers,
T
#17
_Bomber Watson_
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Posted 05 September 2010 - 05:17 PM
http://www.summitrac...universal joint
Should be able to get them in Aus to.
Just measure the size of the cap and buy appropriate ones.
Cheers.
Should be able to get them in Aus to.
Just measure the size of the cap and buy appropriate ones.
Cheers.
#18
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Posted 05 September 2010 - 09:22 PM
There was a little bit of play in the rear uni and when we took the caps off it the little bearing things were crushed and buggered.
That will be the cause of your vibration.
Dave
Edited by S pack, 05 September 2010 - 09:24 PM.
#19
_SLR Goat_
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Posted 05 September 2010 - 10:25 PM
http://www.driveline.com.au/
they have a shop at archerfield
they have a shop at archerfield
Edited by SLR Goat, 05 September 2010 - 10:25 PM.
#20
_Yella SLuR_
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Posted 06 September 2010 - 07:04 AM
Good to hear you got it sorted Tony.
#21
TerrA LX
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Posted 06 September 2010 - 10:00 AM
Tony make sure your uni is seated properly after you put your diff back in
Yeah apart from this I would agree with fastEHholden.
Look up setting pinion angle for G/box/shaft/diff alignment.
Oh just seen you found the problem.
#22
_Big T_
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Posted 06 September 2010 - 11:58 AM
Just got the word from the tailshaft fixing dudes. Both Unis were shot. Tailshaft was also not balanced properly. They are replacing the unis, balancing the shaft and supplying me with high tensile U Bolts. Should cost about $250 all up.
Hopefully (fingers crossed) that is all the problem is.
Thanks for pointing me in the right direction guys
Hopefully (fingers crossed) that is all the problem is.
Thanks for pointing me in the right direction guys
#23
_Big T_
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Posted 09 September 2010 - 09:34 AM
Quick update.
Put the balanced and fixed tailshaft in last night and went for a test drive. There is still a slight vibration from 90-110 but it is nothing like the teeth rattler it was before. I need to check that all my bolts (engine mounts, trans\crossmember etc) are all nice and tight as the bad vibration no doubt loosened things up.
Overall, quite happy with the result.
Thanks heaps for the help and education.
Cheers,
T
Put the balanced and fixed tailshaft in last night and went for a test drive. There is still a slight vibration from 90-110 but it is nothing like the teeth rattler it was before. I need to check that all my bolts (engine mounts, trans\crossmember etc) are all nice and tight as the bad vibration no doubt loosened things up.
Overall, quite happy with the result.
Thanks heaps for the help and education.
Cheers,
T
#24
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Posted 12 September 2010 - 09:32 PM
Hi Tony
The remaining vibration you speak of might just be an engine resonance/harmonics vibration in the exhaust system.
The remaining vibration you speak of might just be an engine resonance/harmonics vibration in the exhaust system.
#25
ls2lxhatch
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Posted 12 September 2010 - 10:21 PM
The pinion angle could still be the cause of the vibration and the reason why the unis failed.
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