[jpk4wd]

Hi Guys, I'm new to the forum & I am after some advise. I have a 89 Sierra that I have fitted 2in EFS leafs & all new bushings with extended shackles & 30" tyres on 7" F100 rims. Since fitting the lift the car gets "deathwobbles" at 80kph. We have balanced the tyres, adjusted the steering box, removed the sway bar & fitted a Tough Dog RTC steering damper & we are still gettig the wobble. Any suggestions on how to solve this issue would be greatly appreciated.

[want33s]

Check the toe.
Check kingpin bearing condition and preload.
Check wheel bearings.

Go get a wheel alignment and ask for the caster figures. You may need to fit caster wedges between the diff perch and the spring.

[SierraDan]

After that, extended shackles may need to addressed.

[royce]

Make sure your ubolts are all evenly tight, and tight enough

do your shackles up tighter, if it changes the wobble remove them and fit the stock ones and try that

[Gwagensteve]

Put the stock shackles back on - 90% it will go away. You've reduced the caster.

Steve.

[tanshi]

if your getting 80km/h out of it before it starts wobbling i would check the wheel balance.