HICAS tie rod ends, vibration, and alignment question

[elwesso]

Well here's the deal.. The last few days when im driving on the highway, the back end feels really squirrley... It seems to jump around somewhat randomly it seems.... its nothing unsafe or anything but it is getting a little annoying... I looked in the FSM and I didnt see anything where it would tell me how to inspect a HICAS tie rod end. It looks like theres a bushing on the hub... Not sure if that goes bad or if that could be replaced...? I have to readjust my sway bar so maybe that has something to do with it. I also need an alignment hardcore, which leads me into my next situation..

I was told by Chet that this is what I should set my alignment specs at:

1*35' camber all around.04 toe in (basically just enough to be barely toed in)7* caster

Do you all agree with this? I want something that handles really good but I dont want to replace my tires a lot. I want it to track fairly good... Car is fairly neutral with my current tire setup, if anything it oversteers a little. Turn in under braking tends to be a little oversteer... I was on an off ramp and slammed on the brakes going into a turn and back end went flying out on me a little... I think i need to retighten my front sway bar a little too...

Current suspension

Tokico blues with california custom springsSPL Front upper links, tension rods, rear upper links, subframe spacersNitto 555 225-45-18 in front, bridgestone RE050 265-40-18 in the rear.

[elwesso]

I forgot to add the ditty about my vibration...

Its been this way since I owned the car... Vibration after 80mph, replaced driveshaft and it took away the vibration before 80, feels real nice.... Driveshaft is a stock rebuilt one from power train industries.... New driveshaft took a lot of the vibration away, its not nearly as bad as it was before... After 70 before it was almost unbearable, now it becomes noticeable at 80ish and then becomes a little unnerving after 90.....

im going to try and change the orientation of the driveshaft on the differential and see if that does anything. I also replaced my wheel bearing in the Right Rear for one reason or another (not sure why, shop said it should be replaced?) and that did nothing....

[elwesso]

No one???

[evildky]

you might want to rake a closer look at your rear strutsmy z32 was very squirley when hitting bumps and expansion joints on the interstate, I replaced the rear struts (one was completely blown and the other had very little pressure left) and problem completely resolved, as for the hicak tie rod ends if you can detect play at the wheel you got an issue if you can't get any play at the wheel and the sockets seem to be snug and in good condition you should be fine

[DAEDALUS]

The knuckle body has a ball joint pressed in. Pull off the tie rod and feel the ball joint for smoothness. Or better yet raise the wheels in idle and have someone try to rock each wheel left to right while you watch for looseness anywhere. What's the spring constant of the springs and what is their free length?

[Exar-Kun]

D- he doesn't know the spring rate...it's one of the problems I encountered in trying to help him with his suspension setup. I have the sneaking suspension those Tokico blues aren't even close to matching the spring rate for him, much less with the limited travel.

Wes: -1.35 camber all around. Starting point anyway.

I'd also double check and ensure you have a hub ring on the wheels and that the person who balanced them indexed the tires, etc.

-Chet

[elwesso]

I actually got to thinking and i think the weird feel in the rear might be due to the poly bushings on my rear sway bar, obviously they have much less give then regular bushings.... so that could be part of the problem.. I will proabbly go back to OEM.

I think I may have isolated the vibration and I think it is probably on the flange of the differential.. its probably not set right... so theres a spec in the FSM to measure the surface and side runout and then remark it, and then reposition the driveshaft to minimize vibration..... Im going to try that first....

My rear struts are brand new with springs that drop the car 2in ... but it doesnt look much, if any, lower than the eibachs that I had, and they also dont feel any stiffer.... I would assume they are roughly the same stiffness as the eibachs, but they are progressives anyway....

I dont think i need a hub ring, since I have the 350Z wheels, they should already be hubcentric... The vibration is no different with a different set of wheels..... These wheels were balanced on a hunter 9700..... Didnt need much if any counterbalancing..

it seems to me with the tie rod ends that one should replace the bushing that is in the hub? Is that replaceable? Everything seems fairly tight back there....

[DAEDALUS]

It is not a bushing, it's a ball joint, and yes, it is replaceable.

[elwesso]

It is not a bushing, it's a ball joint, and yes, it is replaceable.

Heres what im referring to..... highlighted in red. The purple is the ball joint your talking about but im not sure what that goes to.. the highlighted part, correct me if im wrong, has the HICAS rack hooking into it....

[DAEDALUS]

That would be the lower strut bushing (which is indeed probably shot). Loosen the upper strut nuts and remove the lower bolt, then pry the strut off the bushing to see if the rubber's torn.

[elwesso]

That would be the lower strut bushing (which is indeed probably shot). Loosen the upper strut nuts and remove the lower bolt, then pry the strut off the bushing to see if the rubber's torn.

oh... OK... That makes sense, i see whats going on now..

Ill check the wheels sometime and see if theres any play, if i recall correctly there wasnt any last time i checked...

Thanks for the help guys!!!!