Aftermarket Suspension

[Bobby15hill]

About seven months ago i put on a 4 inch suspension lift and now my front suspension shakes around 40 miles an hour. I replaced the shocks with ranch rs5000 and it is still shacking. i was wondering also if my coil springs could be the culprit. I just want to get help because the vibration is insane.

 

[TexasNomad]

If the shaking starts at 40mph and stops once you drop below I think you have a tire out of balance.

 

[countryboytn]

Welcome to FTF!

I'm not sure about your problem...maybe post up some more specs (vehicle, year, etc.) and somebody should be on who can help you either tonight or tommorrow....


EDIT: Tex beat me to it.....lol

 

[LEB Ben]

First I have to ask, does it continue after 40mph or does it 'trim' out? If it continures, I'd say it's either a tire out of balance or the d-shaft threw a wieght and is out of balance. If it 'trims' out sounds like the beginning of the dreaded Death Wobble. In which case, check TRE's, drag ling, trac bar etc. and tighten/replace.

 

[TexasNomad]

I'd just check for tires being out of balance or maybe out of round, swing it by a tire shop and have them balance them.

 

[Skandocious]

First I have to ask, does it continue after 40mph or does it 'trim' out? If it continures, I'd say it's either a tire out of balance or the d-shaft threw a wieght and is out of balance. If it 'trims' out sounds like the beginning of the dreaded Death Wobble. In which case, check TRE's, drag ling, trac bar etc. and tighten/replace.

Good post Ben. Follow what he said above, that pretty much covers all bases.

It's pretty unlikely that your front springs could be causing the vibration unless something isn't secure. I'd look more towards out of balance tires, and if not it's probably in your steering.


And Welcome to FTF

 

[Bobby15hill]

Well i work at discount tire and i have checked the balance the balance of my tires. My truck is a 1992 Ford F150 2wd super cab short bed. The wobble is scaring me a bit. I dont want to end up killing myself while driving.

 

[Bobby15hill]

The vibration continues above 40 miles an hour. im also thinking about checking the front bearings in my hubs.

 

[Bobby15hill]

I also am running 33 12.50 15 goodyear wrangler MTR's. any suggestions

 

[blacksnapon]

Uftfball has it. Its the dreaded "death wobble". Its common in anything with coil springs and a live axle. With this type of setup, you have a "panhard bar" under there. Its a bar that runs from the frame across to the other side of the suspension. Its purpose is to keep the suspension centered under the vehicle. The bushings on either side of this bar get worn, allowing this spooky oscillation. Aftermarket companies make 3 piece plastic replacements that work quite well.

 

[flareside_thunder]

Also go through and retorque every nut/bolt that got touched when you did the lift........