[JonnoR]

Hi Guys,

New to here, this is my first post.

I was having some steering issues with my Coily Sierra, it would sometimes pull itself across the road, and sometimes when you hit a bump the steering wheel would shake pretty bad. There was also a vibration in the steering wheel at >60 kmh.

I got the mechanic to check the front end, and they said everything is fine. So I changed the tyres back to the stockies and the issue seems to have gone away.

I want to put the 30's back on, but obviously without the steering issues if possible. My offroad tyres are 30x9.5 R15, but when I was changing them, I noticed that one of the wheels, rear drivers side, has a different offset to the other 3 rims. 3 have a negative offset of about -40 which is pretty large, and the 4th rim has an offset 0, so the difference between them is pretty big.

My thoughts are:

The difference in the offset could be causing the car to pull/wobble on the road. Could this be right?
Could the large -ve offset of 40 be causing the steering to shake when I hit bumps?
Wheels need to be balanced?
Steering alignment?

Any help/comments appreciated.

Cheers.

[Fatzook]

Could be any of the following, or a combination of many of the following.

Worn tie rod ends
Worn King pin bearings
Worn wheel bearings
Wheel balance
wheel offset
tyre condition
tyre pressure
worn/ poorly adjusted steering box
worn struts

and probably a few other things I can't think of at the moment. Given that you swapped the tyres and it went away, I'd start there. Get the big tyres balanced, chuck them on and see what happens. If no joy, start on the swivel hubs/ king pins/ wheelbearings. And consider fitteing a steering dampener.

[JonnoR]

Fatzook wrote:

Could be any of the following, or a combination of many of the following.

Worn tie rod ends
Worn King pin bearings
Worn wheel bearings
Wheel balance
wheel offset
tyre condition
tyre pressure
worn/ poorly adjusted steering box
worn struts

and probably a few other things I can't think of at the moment. Given that you swapped the tyres and it went away, I'd start there. Get the big tyres balanced, chuck them on and see what happens. If no joy, start on the swivel hubs/ king pins/ wheelbearings. And consider fitteing a steering dampener.

Thanks for the reply. Yeah, I was thinking balancing the tyres would be the first things to do.

The guys at the garage checked the steering and suspension, couldn't find anything wrong. I have them inflated to 20 on the front 22psi on the back which should be fine (I reckon). I have had the steering box adjusted recently so don't think that will be the case.

I presume the different wheel offsets won't help though?

Cheers.

[christover1]

Make sure the odd rim is on the back, that will rule in/out that as a cause.

Most often it turns out to be a small fault in car,
that gets exaggerated by larger tyres and big offsets.

Quite often the steering stabilzer (looks like a shock on steering gear) can be a problem,
without it being obvious.

[Ace]

^^ Bigger tyres will amplify a problem (more leverage) and may not be detected but still worn with your stock size. could be a combination of the above mentioned a little sloppy - or only a few fully fkd. possibly put the front end on axle stands and have a feel for play?


Buy another matching rim for your 3 and keep the odd 1 for a spare?

[1DYX]

The tram lining may be caused by the tyres being too wide for the rim.
All my Sierras did that when I was running 255/60R15 on a 7" rim.

I had the shakes as well in my coily, but it has dissapeared since I replaced all the radius arm bushes.

Balance is a cheap check, and don't forget to check for bearing play while the wheels are off the ground.

[Fatzook]

christover1 wrote:

Quite often the steering stabilzer (looks like a shock on steering gear) can be a problem,
without it being obvious.

Coilys don't have steering dampeners. Its worth fitting one though.

[TrevorStaader]

I had this problem and just got my wheels balanced like everyone else is saying and it went away. Goodluck.

[sideways]

I had this problem, then my tyre exploded and the problem went away.

[barnoon]

I have a very similar problem, see my thread for some more tips viewtopic.php?f=5&t=38238

The wobble I get is quite major with my 31s, comes around 65 kph - 80kph, thing is it doesn't do it all the time, some days it will do it constantly all day, other days its barely there. I had my front wheel bearings replaced, wheels balanced, front brakes rebuilt, discs replaced and it's still there. Put a set of stockies on and whilst the problem is still there it is nowhere near as severe, I guess as the tyres are so much smaller and lighter it doesn't get its wobble rhythm up so bad. Haven't had any time or money to chase the problem further at the moment so I'm just learning to live with it for now.

[Gwagensteve]

I'll just reiterate that whilst a badly balanced tyre or out of round wheel might initiate death wobble, it has very little to do with the weight or size of the tyres themselves.

I've driven cars that don't death wobble with 35" Swampers, unbalanced, on offset, beadlocked rims, but death wobble badly with stock tyres.

A bent wheel or out of balance tyre will cause a wobble at the steering wheel, for sure. For that to turn into death wobble (as in self-perpetuating, massive, uncontrollable shake) there is a problem with one of the wear areas of the front end.

Kingpin bearing preload and the condition of the knuckle seals are the things that seem to work to fix this more often than not.

It is possible to fit a steering denial to mask the problem. (Oh, sorry, I meant steering damper ) but whatever is worn out of spec is still worn out of spec, the damper just masks it. It's like turning the radio up so you don't hear a bearing noise in my opinion.

Steve.

[christover1]

I have watched a death wobble from a vehicle in front, to help decipher a problem.
In that case I could see the drag link bowing up n down like a spring.
Not that it proved it was a drag link cause, or result of other issues.
Changing the drag link solved that issue, but owner decided to put a beefier one on, just in case.

[JonnoR]

Cheers for the help guys, I will first take it down to the tyre shop when I get a minute and get them to do a wheel balance. Hope that cures the problem.