Stock ride height

[scott2093]

You're supposed to make sure the upper and lower ball joint nuts are tightened at proper z height. As well as both the control arms....
At least on my 93...
Everything mentions jacking up the control arm or whatever to install the nuts (must be installed at proper z height)...then lowering the vehicle... Obviously you can't put the weight of the vehicle when doing the ball joints..
Trying to wrap my mind around the proper way to do it and hopefully it'll spark a memory of how I did mine...

 

[caw_86]

Thanks for all the advice, sounds like a problem foe future me to deal with

 

[Schurkey]

You're supposed to make sure the upper and lower ball joint nuts are tightened at proper z height.

Ball joints don't matter. The stud just moves in the socket to where it needs to be. The issue is getting the stud wedged into the steering knuckle tight enough that it doesn't spin as you tighten the nut--same as tie rod ends and other tapered-stud items.

As well as both the control arms.

Bonded rubber control arm bushings do matter. Polyurethane bushings aren't bonded, so they don't need to be at "Z" height either when the control arm bolts are tightened.

 

[scott2093]

Ball joints don't matter. The stud just moves in the socket to where it needs to be

Why do you suppose the manual says the big nuts need to be tightened with the control arms at z height?

And with the control arms, would the z height be off when putting vehicle weight on them for the simple fact that they are not tightened? I'm trying to remember how it worked. Sorry if it seems obvious.. I'll look into it..

looks like I posted some questions and my methods somewhere else a year ago when I was dealing with this. I don't even understand my question..lol

Z height position?

I'm about to replace upper control arms on my 1 ton 2wd c3500 crew cab. Alldata manual says to tighten the upper control arm bolts to 140lbs with control arm at z height position? Im confused and don't really know anything on Z height position or if this even applies to my vehicle? Can I just low...

www.gm-trucks.com

 

[Schurkey]

Why do you suppose the manual says the big nuts need to be tightened with the control arms at z height?

Gonna have to look that up some time. I can't think of any reason that it would matter--since the ball joint ball and socket are intended to wiggle around in-use.

As said...if the tapered stud doesn't spin in the tapered hole as the nut is torqued, it shouldn't matter. But that stud does have to be secure in the hole.

And with the control arms, would the z height be off when putting vehicle weight on them for the simple fact that they are not tightened?

Not enough to matter. The whole point is to assure that the bonded rubber of the control arm bushings spends most of it's time unstressed in torsion. The rubber twists when the control arms jounce "up", and it twists the other way when the control arms rebound "down", but at normal ride-height (parked overnight) they should have no or minimal twist--meaning no or minimal torsional stress.

Guys tighten the control arm bolts with the suspension in full droop, so that when the weight is on the suspension, the rubber is twisted, and twisted twice as far as intended when the suspension moves "up". About two weeks later, the vehicle settles because the control arm bushings have ripped the bond between rubber and steel, and the ride-height lowers a little. Then the guys say that the springs have settled. No, it's not the springs, it's that the control arm bushings are no longer trying to push the control arms down, raising the vehicle.

 

[scott2093]

Gonna have to look that up some time

I added some uuper bj,lower bj...upper ca...pics from my 1993 Sierra/yukon/suburban/crew cab/and 3500hd manual..
Even the upper ca says drop vehicle after tightening at z height......and the lower ca says put ..axles...wheels and tires on after all the tightening at z height...

I think from my post on another forum, I must have jacked up the control arms and tightened everything at what I came up with for z height......But when I dropped the vehicle, my z height was off so I did something from there to fix that..Just can't remember exactly how I went about it....
My truck does have a slight + rake /lower in the front but I always thought that was normal for stock

 

[Schurkey]

Interesting that the text says "131" is a nut, while the illustration shows 131 as the Lower Ball Joint, and doesn't show the stud nut at all.

Again--I have NO idea why the stud nut needs to have the suspension at Z ride height before tightening. The bushings, I understand.

 

[scott2093]

Interesting that the text says "131" is a nut, while the illustration shows 131 as the Lower Ball Joint, and doesn't show the stud nut at all.

Yeah there are a lot of interesting things in the manual....forget about tracing ac circuit in my wiring manual......still a project for later...

127 is the lbj..that checks out --of course diagram (hub,knuckle and control arm components--notice the 5 lug 4wd section...)is a few pages back to verify where they came up with that...... And the nut is 124....
but even the steering knuckle install says lbj nut is 131....
I'd like to be shown my error in seeing things . It usually makes me feel much better...maybe 131 was missed from a previous year or manual...idk...

 

[Erik the Awful]

When I swapped my Mustang's control arms, I put jackstands under the control arms as close to the ball joints as I could get them before fully tightening the inner control arm bolts. The ball joints do not need weight on them, tighten them when you install them.

WCJr's on poly, so I just tightened them when I installed them.