98 V79 NA front end vibration (control arms replaced) Topic is solved

[clifford06]

Greetings. I agree that at 60-70 mph is more than likely control arm issue. I had the same problem and removed my pass. side control arm. Mine didn't wobble during the push and pull test. The ball joint was wobble wobble by finger touch. Rubber boot looked great. I would start there because its less labor intense and won't mess with alignment.
I removed my driver side arm and the ball joint was firm. then I saw that the tierod end boot was busted, and the inner tierod boot cover also. I could rotate the tierod assembly front to back. I'll replace the tierod assembly and boot cover this weekend.

[kcodyjr]

misha, I'm interpreting "vibrating" as "something physically oscillating".

Checking front control arms by hand is insufficient. One needs to take a lever and push the bushings around to see how much force they take to move. I'm not quite even sure how to check the ball joints, I let my mechanic do it. The bushings get soft under load long before they get cracked and shitty and shaking around sitting still.

Re: rear bushings. You're right that it shouldn't cause an actual vibration up front unless something else up front is also loose.

4 years ago, I went looking for and found cracked, sagging rear bushings, because it had gotten annoyingly squirrely on the highway, and I'd just done a rack with ends, subframe bushings, and control arms. They weren't making a sound, they were just making straight line stability impossible. I replaced them all with OEM bushings from FCP as a set. It drove like brand new, for a while.

Since then, the right rear outer bushing has failed again, and this time it is making a heavy metal slapping noise.

Thing is, every time a loose rear arm moves, it changes the stance of the car, and if you're trying to go straight, it changes the direction of drift, and you have to chase the wheel to keep it in the lane. The slapping is mostly suppressed during sweeping turns, and with it, the twitching in the wheel.

I'm not sure if this effect could occur fast enough, and in resonance with something in the front, to cause a vibration on its own. Maybe. Probably not. The conditions would have to line up just right. But I could definitely see a rear end problem exacerbating a front end problem.

I'm not saying it's bad rear bushings - but I am saying it's worth inspecting them.

If they're cracked, swap 'em all out. They're 18+ years old.

Moving along.

I think we can rule out a wheel out of balance. That should transmit vibration at any speed, with increasing severity. It wouldn't just show up at 65. It would be there by 15, it would not disappear at 70, and at highway speed, the steering wheel should shake your arms like holding on to an unbalanced fully loaded washing machine on max spin cycle under an overvoltage. Which is actually a near exact analogue of an out-of-balance wheel, except that the washing machine is designed to take a certain amount of that kind of vibration, and a car really isn't.

I could believe that an aftermarket axle might do this, if even one critical tolerance isn't quite right. I could also believe an out-of-true or out-of-round rim might do it. Those would be resonance effects that show up at particular speeds (read: particular frequencies).

I could also believe bad cords in the tires could do it, but I'd also expect other symptoms from that. Handling should feel... squishy in the details, even at moderate speed? Is that a good way to describe it?

[kcodyjr]

Also... every other front end piece is new, including tie rod ends? That's a reason to swap out original control arms right there. Surely the tie rod ends will live a longer life when mated to a brand new ball.

[misha]

You're wrong about wheel balance.Wheel without any weight at all,un-ballanced with a good tyres will not make steering wheel wobbling up to 60km/h.The fact is that up to 60km/h you don't need wheels to be balanced.A reputable tyre installer told me that once.

Other thing....unproperly balanced tyre can be still up to 120-130km/h and start wobbling at 140-160km/h....after that from 160 and higher can become still again without wobbling.

I also had experience that unproper balanced NEW tyres were perfectly still up to 100km/h and at 105 and higher would wobble like mad.

Got them rebalanced at reputable tyre shop and all the wobbling disappeared.
Got perfectly balanced wheels at any speed up to 200km/h.

New tyres from most manufacturers have 3 class of quality....at least in Europe.1st class is the best....etc.

Maybe 98v70dad got bad ones from the factory....2nd or 3rd class.

[98v70dad]

I appreciate everyone's comments. They are helpful. However, this is starting to be a long thread and many people have overlooked a few important key points. I had a vibration problem and needed new wheels and tires anyway (tires worn out and 2 of 4 alloy wheels bent) so I bought new wheels and tires. I had the car aligned. I still had the vibration problem. I had the new tires balanced again. I still had the vibration problem.

I had the vibration problem BEFORE the new wheels and tires and I had the vibration problem AFTER the new wheels, tires and multiple tire balances. I haven't mentioned it in the thread but I actually had the problem over a year ago BEFORE and AFTER putting a set of new tires on the front. So there have been two sets of new tires on the front and the vibration problem persisted after getting them installed. In other words, the vibration problem has been persistent and has outlived several sets of tires on the front end.

Concluding that I got a bad tire or the wheels aren't balanced would make sense to me if the problem didn't exist BEFORE I bought the new wheels and tires. While that is possible I think that it is unlikely in my case.

[kcodyjr]

Re-check the control arms properly with a lever, or take it to an independent Volvo specialist and have him check it.

Joe's Garage is not helpful with your Volvo, and the stealership will happily quote you an $8000 new motor to solve a worn spark plug.

[98v70dad]

Re-check the control arms properly with a lever, or take it to an independent Volvo specialist and have him check it.

Joe's Garage is not helpful with your Volvo, and the stealership will happily quote you an $8000 new motor to solve a worn spark plug.

Based on what my independent garage charges I'm better off cost wise figuring out the problem myself and repairing them myself. If I am not correct and have misdiagnosed it I still have a new part in my car when the old part was 18+ years old and would possibly have failed soon anyway.

Using this philosophy I haven't "wasted" money too many times.

[kcodyjr]

Based on that logic, by all means, replace the control arms.

I'd choose only Lemforder, either from FCP or as a used original part from Erie, but I've not heard complaints about the Meyle HD ones.

Do not under any circumstance use a cut-rate generic aftermarket control arm. Do not use different brands on each side, either.

[erikv11]

Just a heads-up: recently, Lemforder CAs have been cheapest at RMEuropean.

[98v70dad]

I dont know what they hit but a month later I noted the torn boot on the drivers side axle. On the passenger side I don't know if it hit anything but maybe it hit that long axle long enough to bend it a bit.

Thoughts?

Did you replace the entire axle with a good non compromised axle assembly?

No, not yet. Its on my list of possibilities.