VT Shudder at 100 kph

[C-change]

After some advice if anyone has had something similar.

My old 98 VT V6 wagon with 280,000k's had been running great until recently. It has always been very smooth and comfortable to drive and I've had it since 30,000 k's. Anyway now when I drive at 90-120kph I get this annoying shudder through the steering and then the whole car does it. It only starts at 90 k and gets worse the faster I go. Its minor, nothing violent and can be tolerated on the 20 min drive to work but a few hours on the Hume Hwy or the F3 and it drives me mad.

Here is what I have had replaced, fixed in the last 6 months.

New steering rack, lower control arm bushes (front right), left tie rod, new brakes and rotors all around plus 4 new tyres.

When it first started I thought the old tyres were the problem. Mech thought so too but with new tyres there is no change to the shudder. I've had the new tyres balanced 3 times in 3 weeks and no change.

Got me stuffed, any ideas ?

[mustafa76]

it could be universal joint or center bearing in the drive shaft

[jafo]

wheel and camber alignment might help
or as mustafa76 said

[vy-346]

Sounds like a problem with one of your rims, I just had a similiar thing in my VY at xmas after driving through a shitload of mud on hols, and it dried onto my rims and put them way out of balance. Are your rims just the factory steelies or are they Alloys, maybe try borrow or get a cheap set of chaser rims and whack them on and see if it changes anything.

[jazza15]

I have the same problem, this has come up on a few other threads, very similar/same symptoms and people have tried very similar/the same things to try and fix it to no avail.
I have replaced every bush in the front suspension, the steering rack and one of the first things i replaced was a tie rod end.
I started my VY IRS conversion today and currently have the whole IRS out of the car. Before i did this i had the rear wheels off and ran the car in 5th to see if i could see anything wrong. The rear left brake was making a bit of a noise, but my mate said it probably isn't it. Seeing as you replaced all of your rotors, i'd probably say it isn't it too.
More interestingly i found that my left side outer cradle mount bush was completely torn upon removing it. I doubt that i could have done that while removing it and the right side one was pretty much fine. This could be sending that vibration through to the steering wheel.
My other possible option is a bent half shaft (diff to trailing arm), but i didn't see anything of significance during my 'diagnostic test'.
Only other possibility is my front left wheel bearing as it has been gone for some time now.
Good luck with it and let us know how you go, as will I

[C-change]

Thanks all for the suggestions, I'll work through them starting with the cheapest first. Going to take the mech for a ride next week to prove I'm not mad and then go from there.

I was worried that the new rotors might be warped but they reckon thats not it and all suspension components seemed fine when they checked last week. I feels like its coming from all four wheels which makes me think thats where the problem is. Even the kids in the back were complaining about the "shaking" today and that was on the new Dunmore section of the Princes Hwy near Shellharbour. Considering this road only opened a couple of months ago, it must be one fo the smoothest bits of road in NSW and it still shook its arse off. The biggest hassle is the cars age and mileage. I don't want to spent a fortune on it, but I would like it to run like it did a few months ago.

I'll let you know how I get on next week.

[GenOktOniA]

my brother inlaws VX did the same thing, he just got a wheel alignment and that sorted it out, i recomend starting there

[holden_calais_VT_1999]

i am not 100% sure but maybe take it to a suspension specialest in sted of ur normall mechanic and let him take it for a drive. thats what i did he he new what it was straight up. just a surgestion hope it helps cheers

oh and sorry cant remember what the excat problem was

[jazza15]

Thought I'd just update you's on how mines going. Just finished rear suspension overhaul, now every suspension bush, bar stab bar bushes has been replaced.
I will be finally getting a cradle alignment and 4 wheel alignment tomorrow. I believe things like wheel alignments (and new radius rod bushes) will only help dull the symptoms, not fix the actual problem.
I mentioned earlier that my rear left rotor was making noise, I switched it over to the right side, same noise, it has to be warped. I think that's the source of my problem, not much of a surprise as they are getting along a bit, have a fair lip and this particular one has some scoring on it from when i put a brake pad in the wrong way one time :~
A while back when I hijacked someone else's thread about the same sort of problem, someone came up with a general rule of thumb that below 80km/hr it is the front brakes, above 80km/hr it is the rears. Turned out to be a good rule for me I reckon.
One thing you can try doing if you have the equipment is jack your car up and put it on axle stands. I ran mine in fifth moving the wheels at around 40km/hr at idle speed (i figured using the accelerator could get a little bit dangerous), so with an auto you might want to come up with something a bit ifferent to test it.

[50LTRv8]

When you brake, do you feel a vibration through your shifter?

[Tsunamix]

Warped Rotors
Warped Rim
Warped axle (not propshaft)
Poor front alignment

Remove everything on the list that is rev associated instead of road speed associated. It own't be propshaft or prop bearing or gearbox or engine / engine mount associated. I'd be starting with the rotors (common), then alignment as the most likely culprits.

[LowVtWagon]

hey mate, just try getting 4 wheel balances. one of the wheels might have just thrown a weight. usually a shudder will come in about that speed then go after about 110km.

[mark b]

My car had a similar problem last month, mine has done 210 000km's and shuddered round 100 an would go away round 120. I got a full wheel alignment/balance an this fixed half the problem. I got a REAR CAMBER KIT an that fixed the other half of the problem.

Ive read from a few posts that 98 VTs often need Camber Kits at about 200 000km's ( as well as a new key, fuel pump & injectors! ) I may be wrong but if you put a strut bar in early a lot of these suspension problems MAY be avoided.

[gussy17]

you might have a buckled rim. or if you got all new rotors and they didnt clean the surfaces on the wheel bearings it will cause them to run a bit rougher. depends on the dodginess of the person working on the car

[s_ikari2015]

I've had the problem since the day I picked up my 2002 CV8 Monaro. Over 100km/h you get a constant vibration that feels like wheel alignment, but the car tracks perfectly. It vibrates through the car and while you get vibration through the steering wheel it's more of a reaction to the actual vibration, and not from the steering.
I got a puncture on my rear left last week and have been using a couple of old steelies, the vibration is still there but I think the wheel balance was out on the mags as it isn't as noticable. I'll be getting a 4 wheel balance and alignment when I replace the tyre and going from there.
I'll probably be looking at bushes and mounts, particularly driveshaft, afterwards too because I think I've got a bit of play and unusual wear.

I wouldn't be surprised if the dealer principle (who drove the car before they sold it) hit a few kerbs. There's evidence of kerb contact on the rims that I know I didn't do and they're apparently brand new.

If it's a warped wheel or rotor then the Dealer is paying for it under statutory warranty. If it's just wheel balance and alignment then they aren't liable as that could have happened the day I picked up the car and drove it out of their driveway, not that it did.

[LowVtWagon]

doesnt matter if a car is tracking straight, the toe setting could be out which can still cause premature wear, but still drive perfectly straight.

[Paiste402]

sounds like a wheel weight has fallen off. it happens now and again and it causes the car to shudder cause of the imbalance

[C-change]

Back again. Finally managed to get the old girl looked at today and after a very comprehensive inspection and several test drives, they beleive its worn shocks causing the problem. After checking records at home they have been on the car since 2003 and done 170K kms. Everything else checks out ok. Propshaft, universal, wheels, weights the lot. All ok.
Will be booked in next week and I'll let you know if it was the culprit. Fingers crossed.

Someone asked about brake shudder earlier, getting none in the front or rear brakes. Braking performance was very good.

[And_ROOS]

When you brake, do you feel a vibration through your shifter?

I do sometimes, care to tell me what this means when it does that?

[s_ikari2015]

I've noticed quite a bit of play in the left axle. Could this be part of the problem or is that normal?

[C-change]

Problem solved, it was the bloody tyres.

Boys started on the shocks and replaced rear shocks and went for a drive, still shuddered. Went back and had set of new steel rims, fitted new tyres and went for a drive, no shudder. Then put my tyres (bought Dec) on new rims, went for a drive and shudder was back. Put new tyres on my rims after checking rim balance, without tyres, and no shudder. Back up on hoist and replaced new rear shocks with my old ones and no shudder (if they called I would have left new shocks on and saved some work but no probs).

So problem solved. Whilst the tyre manufacturer is a fault, I must thank the boys that worked on it today and last week. Probably 10-12 hours work and for no charge. Probably fair enough to expect that but would also have been very easy to charge for shocks and then replace other stuff trying to solve this problem.

Will certainly be back for more work in the future and its nice to have the old girl running smoothly again.

[LowVtWagon]

hope ur took the tyres back and got brand new ones fitted!!!!

[C-change]

Yes mate, sure did. The blokes that did the work also fitted the tyres. They're a Bridgestone tyre centre so they took care of it. They're sending old tyres back to Bridgestone to check them out. Same brand of tyre fitted and no drama's with em so must have just got a couple of crap ones back in Decemeber. All good now.