vibration @ 105+ in Brumby

stinky · Post by **stinky** » Sun Dec 17, 2006 3:01 pm

The last week or so the moment I hit around 105 in the brumby I get a really audible vibration, I don't really get any extra vibration through the steering wheel. Sounds and feels like I'm just driving over really bad road.

Any ideas what it could be ? I not long ago did most of the bushes in the front end, and have brand new front struts and springs. CVs are in good nick, and steering rack feels fine.

Suby Wan Kenobi · Post by **Suby Wan Kenobi** » Sun Dec 17, 2006 4:11 pm

You may have thrown a weight on a rear wheel or have a tyre thats sad on the rear.

SuBaRiNo · Post by **SuBaRiNo** » Sun Dec 17, 2006 5:58 pm

Wheel Bearings? Is it like a roar sorta noise?

Dave

stinky · Post by **stinky** » Sun Dec 17, 2006 6:06 pm

tyres are fine ... I did both front wheel bearings within the last 12 months ... but I guess it could be rear bearings. Yeah it is a roar sorta noise.

Suby Wan Kenobi · Post by **Suby Wan Kenobi** » Sun Dec 17, 2006 6:46 pm

I only say rear as once you have eliminated the front end being an issue the rear can present very similar effect if there is a problem back there. If its a wheel bearing you have scraping noises for a while before shuddering. Another possibility could be a tailshaft uni.

stinky · Post by **stinky** » Sun Dec 17, 2006 6:52 pm

Yeah I would expect scraping noises from wheel bearings which I haven't had.

I just had the tailshaft uni replaced and shaft rebalanced ( $200! I think they took me to the cleaners ) because it was noisy. Actually now that I think about it, this noise probably started about the same time I did that ...

SuBaRiNo · Post by **SuBaRiNo** » Sun Dec 17, 2006 11:00 pm

I still would not rule out your rear wheel bearings... Mine went... never heard the scrapping your refering to... Just a roar at particaluar speeds... ignored it till one day the rear wheel locked solid on me.

Dave

stinky · Post by **stinky** » Mon Dec 18, 2006 9:33 am

yeah I think I'll ignore it until xmas is over ... trying to find a mechanic who'll take it in is hopeless ... I guess I could try someone like beurepairs ? but that sounds scary letting a tyre guy at my bearings.

Cynical · Post by **Cynical** » Mon Dec 18, 2006 12:03 pm

i've had tyres go slightly oval shaped on me before, and give similar vibration, you can check this by letting some air out of the tyres, if its the tyres the vibration should go away.

just a thought...
Cynical

Fang · Post by **Fang** » Mon Dec 18, 2006 12:22 pm

stinky wrote:yeah I think I'll ignore it until xmas is over ... trying to find a mechanic who'll take it in is hopeless ... I guess I could try someone like beurepairs ? but that sounds scary letting a tyre guy at my bearings.

I had a similar situation last Christmas. I reluctantly took my car to Midas for some suspension work. But they were pretty damn good. This was the one in Mansfield - don't know how others are.

BlackMale · Post by **BlackMale** » Mon Dec 18, 2006 2:44 pm

So it does not occur before 105, does it go away after you have passed the 105 (ei 110, 115km/h) or does it still continue to vibrate?

stinky · Post by **stinky** » Mon Dec 18, 2006 4:26 pm

It's happened a few times randomly at other speeds, like 2 or 3 times, but consistently at 105. I haven't tried to take it past it ... don't really want to.

BlackMale · Post by **BlackMale** » Mon Dec 18, 2006 5:27 pm

Awww don’t really want to COM’N!!! No only joking. Sorry i am a lil brain dead this arvo...

OK this 1 going to sound weird but its possible that you have found the harmonic balance of a component for it/them to resinate.

I asked if it goes away as there will be several set (not preset) points where you will just reach the correct frequencies for things to resinate – as as you reported it come and goes, this is always at a few set speeds correct? (note this only applies to this car it its current state). I know we used to own an kitted out Ford Meteor (yes I know) but it used to do the same at about 95km/h and 112km/h.

I take it that you are reporting on something that the Brumby has never done before? Have you changed anything on the car since you noticed the noise? I know it sounds like I should lock myself up and I am not saying that this IS you problem however its worth looking at you will be surprised if something has moved slightly and wind is now dragging around it differently then before it may create the effect your reporting. IF you go faster then 105km/h and it does not go away then yes you have reason for concern and I would not do it either, but you may find that the vibration goes away again.

Trust me larf as you might no straight jacket required - well yet anyway.

stinky · Post by **stinky** » Mon Dec 18, 2006 6:43 pm

after jacking the rear end up and turning the wheels by hand I'm pretty sure at least one of the wheel bearings is shot, with the other not feeling great either.

I've heard replacing rear wheel bearings is a real bugger, so I'll probably find a local mechanic to do it for me.

SuBaRiNo · Post by **SuBaRiNo** » Mon Dec 18, 2006 7:38 pm

Definatly pay someone to do it... u can thank me later... Rear wheel bearings and rebuilding an engine are almost the only 2 things i wont do.

Dave

steptoe · Post by **steptoe** » Mon Dec 18, 2006 8:17 pm

the rear bearings are costly...like 140 0r 170 per side, just for the bearings + labour. I bought a second hand unit for $45 a few year ago. Best option at the time for me. Had no vibration though.

Does this vibration change whether power on or power off at 105 k. When I get this I fix by swapping CV shafts!

BaronVonChickenPants · Post by **BaronVonChickenPants** » Mon Dec 18, 2006 8:27 pm

Yeah you could just replace the torsion bar as a temporary fix.

cameron · Post by **cameron** » Mon Dec 18, 2006 8:52 pm

If you want to do them yourself, I will lend you the tool to undo the locking nut.

stinky · Post by **stinky** » Wed Dec 20, 2006 1:49 pm

The mechanic just gave the car back and said it's the rear diff at fault.

anyone in brisbane got a spare 3.9 rear diff ?

steptoe · Post by **steptoe** » Thu Dec 21, 2006 11:36 pm

a mechanic diagnosed a stuffed front wheel bearing as stuffed diff carrier bearings $1200 quote. A better mechanic found the wheel bearings - a few days before I bought it and the asking price went up accordingly !!