Vibrating between 20-40

[JulianForsyth]

Hey guys,
Recently was coming back up to Townsville from Airlie beach and began to notice my car having a slight vibration in the steering wheel between 20-40km. After about an hour of driving it started to become really full on and you can see my mirrors etc vibrating still between 20-40. The what I assumed was tyre noise has become so bad now also that I can't even drive with the windows up. Even going 40 the noise is unbareable. Took it into JAX for them to have a look because I've been flat out with work and they noticed I had heel toe wear on the rear tyres and told me my rear shocks need replacing and that this would fix the issue. Also did a rebalance and alignment etc. A week later we had a trip up to cairns and noticed that the tyre noise is even worse than before, it is vibrating worse than before and now to add to the problem if I ever go over 90 the car shakes like crazy which didn't happen before I took it into JAX. Took it back to them to have a check over and they said that one of the tyres was a little bit out of balance but they have fixed it up so it Shouldn't vibrate over 90 anymore and that the road noise and vibration I'm feeling will be just from my back tyres having the uneven wear (worn similar to a stair pattern so made sense in my head). Took it for a test drive and it is still vibrating over 90 despite being rebalanced, still vibrating between 20-40 which is coming through the steering wheel prodominantlt, and getting even louder. I am starting to think it is a wheel bearing issue. The noise does stop when the car is turning but to what I remember it will stop no matter the direction I'm turning (making me think that it is just the centre part of the tires where it is uneven having less weight put on them.). A few other things I'm running dessert Hawks xmt's so I know it's going to be loud but this is just crazy. Any ideas would help, can get a set of hubs for about $150 off eBay so thinking of just getting a pair sent and changing them anyway to see.
Cheers,
Julian

 

[Old.Tony]

Taking a bend in the car does load up the tyre, but unless you're driving towards the limit of adhesion, the noise from the tyres themselves won't change appreciably in a corner. Wheel bearings are a different matter. They load up considerably in corners, and a bad bearing will not only make its presence quite clear but it will start to show other signs of its demise - most notably the ABS system. The ABS ring in the front axles is (my opinion) too close to the wheel bearing and a self-destructing bearing will deposit fragments in the ABS ring's teeth, which results in the ABS sensor becoming faulty. You'll apply your brakes gently and the ABS will fire, the ABS light will come on, speedo will start becoming inaccurate ... all signs of a damaged wheel bearing.

However, the bearing itself isn't often a cause of vibration like you described, which is more often attributable to either a damaged drive shaft or poorly balanced tyres. Since you obviously trust the guys from Jax, it's probably time to look at the drive shafts. Both of them too - in the D40, the front drive shaft turns over when the car is moving, it's just not connected in the transfer case.

There are a number of things to check with each drive shaft. First and foremost is vertical/horizontal play. There shouldn't be any - get under the car and grab the shafts and wiggle them. They shouldn't wiggle - mine don't (yes I got underneath and had a look). If they wiggle, inspect the uni joints on each end. If the wiggling extends past the uni (the uni looks solid) then it's the bearing in the diff/transfer case. I've had both of my transfer case bearings replaced, and the rear diff as well. If there's any movement ("slop") in the uni joint, it needs to go. Either fault will cause the drive shaft to wobble while driving, and there's your vibration.

 

[JulianForsyth]

I had a look underneath and found that there is a bit of play in the right hand side which extends through To the transfer case so like you said I would assume it's a bearing in the transfer case. You said you had these replaced before just wondering do you think it is too complicated to do it yourself (I'm not worst but not the best mechanic either) if it is too complex how much do you think I would be looking at to get the front bearings replaced?
Cheers

 

[Old.Tony]

I had my transfer case bearings replaced under warranty and my diff was rebuilt for $3K, so I'm not sure of the cost of the TF bearing replacement. I think others have had the work done, from memory it was only a couple hundred $.