tie rod angle

[texastrendz]

i need the help of some suspension gurus. i have a lot of bumpsteer through the cycle of my suspension. i need a little insight on how a front suspension setup is supposed to work. i have been reading pages and pages of info. the truck is airbaged, from layed out to aired up the tires swing in and out badly telling me i have a bumpsteer condition. is the tierod supposed to parrell with the lower control arm at ride height? i do not know a lot about front end geometry and want to learn. any help would be great.

it is a dual arm with center drag link style front end.

[NZSquare]

Ill have a go at this, Ive been doing loads of reading on it myself the last few weeks.

From what I gather the tie rod angle and bumpsteer condition is more a function of the instant centre than of the relationship to the lower arm, I think plenty of guys use the parallel rule but to get rid of it completely you need to know your instant centre. You can figure yours out with an inclinometer and tape measure.

Heres a diagram:



Then line up the tie rod accordingly (easier said than done)


Im running a chopped crossmember and am expecting the same issue once I get it back on the road. My plan is to flip the tie rods so they install from the underside of the spindle. Im doing this by using these bushings:

http://www.ballisticfabrication.com/...rt_p_1706.html

Ill cut an NF thread down the outside of them, then a matching thread through the spindle. You could just weld them in but the law doesn't allow for that in New Zealand where I am.

I'm new to this so am open to suggestion from anyone else who knows more than me or things what Im saying is "sucks".

[texastrendz]

that is pretty much what i have read also. i have a one ton truck that has all kinds of changes done to it. we narrowed the track with thru the control arms. it has totally changed the front end. i think it will take some testing, frustration, wrench throwing and a ton of beer to get it where i want it.

[texastrendz]

there is a good you tube video a guy does on a car. he shims the tie rod down or up according to the condition. pretty slick gauge he has to check it with. gave me some ideas on how to check how bad mine is. i searched under bump steer and it came up with some videos, some helpful, some not.

[panhandler62]

In doing a mild drop .. say around 5", can I disregard the 3" I get from the drop spindles since they shouldn't do anything more than raise the wheel center without effecting the geometry?

Or, in other words, if I use a 2" spring drop and 3" spindle drop; can I act as though it is only a 2" drop for the purposes of getting the tie rod and sway bar lined up correctly?

[LONGHAIR]

Yes, assuming that the spindle is correct in the first place. It should have the tie-rod mounting location in the same place as your original.