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Triumph TR6 - Wobble at speed
|I've had my '6 for a little more than a year now. When I bought it the suspension was in pretty bad condition, as was the engine.|
It did wobble quite a bit at speed, and the shocks were really sloppy etc etc.
During the winter I have put it through a quite extensive overhaul. Engine rebuilt, and new bushings all around, new shocks, new springs, 4 new u-joints etc.
The PO claimed that he had balanced the wheels just prior to my purchase, so I thought that going through the suspension would cure the wobble, as my mechanic told me that 30+ year old bushings may very well cause all kinds of problems, inclunding wobblin and shaking when the suspension parts get to move more than they should.
Anyway, now the car just runs great, BUT... The wobble at appr. 65-70 mph is still there. Otherwise it rides nice, but at this speed there is very noticable shake. I will get the wheels balanced, but I am afraid it wont do, it is such a strong wobble at this particular speed range, otherwise, as I said, it runs great.
Assuming you are now up to scratch with the mechanicals, it is probably that the tyres have had it, particularly if you have run them for a while on the wobbly suspension.
They are almost certainly out of balance, but are probably also out of round and unevenly worn. You should try re-balancing first. Balancing quality will vary - the best is to get an 'on-car' balance done which balances the hub, rotor (disc), tyre and rim together. Also get the rims checked for straight and true. The wheel bearings also should be up to spec.
Do all 4 wheels, but the wobble back through the steering wheel is most likely front end.
In addition to what Roger said - do you have wire wheels?
|Thanks for the replies so far! No, I don't have wire wheels, they are stock&original as far as I know. I sincerely hope it is the tyres, I am going to get them balanced (and aligned as well while I'm there) on monday.|
I really hope the balancing helps, the tyres are old, actually I should buy new ones but I havent made up my mind about wich I should get.
I just hope it's not the prop-shaft or drive shafts that are unbalanced, I'd like to think that the drive tarin an d suspension really is ok!
When I got my car running, (basket case at purchase) I took it down for front end alignment. As they were hooking the attachments to the front wheels, there was quite a bit of play in the front wheel bearings. The mechanic asked if I had put new wheel bearings in, and told me he found they would gain a little 'slack' after the initial install, and tightened 'em back up. So you might check for bearing play up there!
|SR: Had the same trouble with my '72 when I got it. Turned out the wheels themselves were dinged and bent. Had to replace with a set of Panaracers. No problem since. FWIW.|
|J. L. Stein|
|Put the rear end up on jackstands, remove the wheels and run the car up to speed. You will find out pretty quick if you have a problem with the drive train or if the problem is wheels/tires.|
In my case I was chasing high speed vibration - not really a wobble but a seat-of-the-pants vibration at about 75 mph. Turned out to be one loose rear hub hold-down nut. I was afraid to overtighten for fear of stripping the NF thread in the aluminum trailing arm. (Good grief some of the engineering on these cars makes it nutty to drive fast!)
Anyhow I digress but removing the wheels and running the car in gear is the best way to diagnose a shimmy.
73 5 speed.
|Ya but duck if that sucker comes off the stands with the hubs turning at 75 MPH. You might also check the drum screws before trying that.|
A few pounds of brake drum vibrating loose at that speed gives Frisbee a whole new meaning. You may have to buy your nieghbors pit bull a set of dentures and a new bad attitude.
Take it to the alignment or tire guy easy if you have a few thousand in equipment.
Usually under 50 bucks for the whole works.
That sounds like my wife...
I keep telling her the hubs aren't going anywhere with drum screws properly tightend.
And it isn't falling off the jackstands either.
73 5 speed.
I have been fighting the same problem on my '71 for the 2+ years that I have owned it. Complete new suspension,4 wheel alignment,new tires. I happen to own a tire business and have balanced the tires, replaced steel stock wheels with other steel stock wheels-all to no avail. Even went so far as to replace one of the half-shafts because of slack in the splines. I joined a local Triumph club and brought up this subject with other members. The concensus was that vibration/wobble is endemic to the stock wheels and is best cured by replacing them with alloy wheels. I just rebuilt the engine and tranny, when my bank account recovers my next purchase will be a set of Panasports. It still wouldn't hurt to have the wheel balance checked. If you have the tires replaced make sure they remove them from the backside as the drop-center is reversed. Good Luck
Mike Crane '71 TR6 Sapphire blue
|Well thanks John your wife is likely young and good looking with a lot of common sense. I have all those qualities myself..:)|
Yeah I would do it that way because I have all the right tools and experience. But I don't suggest those idea's on the net. At least without cautions. I never know what the readers level of knowledge or experience is. Or if his tools came from Snap-on or the Dollar Store. Yep I have seen plastic milk crates being used for car stands because the real things are too expensive and these work just as good?.
Mind you I did get a great deal on a TR 250 long ago. Because the young fella launched it through his Dads garage door doing something the same test. Tires on though. Seems he missed his Mom by about a foot sitting in a lawn chair between the car and garage. TR realy only had some bonnet damage but the old mans new Buick was a heck of a mess from all the flying wood door panels coming in the garage.
Just words of caution
|Bill that's a grand response and puts things in perspective. I'v had a few near misses over the years and it is easy to forget the newbs out there who rely on our advice for moving forward problem solving excersises and such.|
For the newbs the worst mistake I ever made while building an automobile was installing a set of rocker arms and at the coarse adjustment stage had one too tight and the end of the casting broke off at high pressure and flew past my eye at the velocity just short of a bullet. I became aware of my mistake as the sound of the tip breaking off was interupted by the sound of the shrapnel imbedding itself in my wall stud.
Yes, you do need to be carefull and think things through to a large extent.
73 5 speed.
|I wrote a lengthy reply to this and must have hit the wrong key...grrr.|
I think what I said boils down to "buy new tires". Don't waste money balancing old ones. If the vibration is still there, at least you're safer. Oh yeah. First check the runout of all the wheels, round and round and side to side. You can make up a simple thing from a wire hanger and a piece of wood, the wheel touches on one side, then measure the gap at its widest (probably 180 degrees around). What's acceptable? 1/8 inch? I need help here. Maybe one of the wheels is worse than the others and the spare is better. Maybe the tire store would do this for you.
|Update on my battle against shaking and wobbling:|
Went to the tire shop. They talked me over to buy new tires (wans't a hard sell really..), they promised to balance them on-car. It turns out that one wheel is out of round, and that the same rear hub bearing is gone too (I've been suspecting the hub, so I asked them to take a look at it while at it), I don't know wich one causes the other one; bad wheel -> hub bearing, or bad hub bearing-> destroys the tire. But I quess it doens't matter...
A new rear hub assembly is on its way to it's new home by now, and I suddenly remembered that the PO mentioned that he once bought a new wheel (for some reason that i can't remember, but...).
Still shaknig and wobbling, but at least I've got new (balanced!) tires, and great hopes for next week when I hopefully will be roaring around at great speed and without any wobbling&shaking (could it be possible?!?!) on a new wheel and rear hub...
SR (still shaking)
This thread was discussed between 27/05/2004 and 01/06/2004
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