Steering issue at highway speeds

road warrior · Post by **road warrior** » Thu Sep 06, 2018 7:44 pm

the rubber joint you speak of, is that no 8 ?

Jakg · Post by **Jakg** » Thu Sep 06, 2018 8:51 pm

Joycey wrote: ↑Wed Aug 29, 2018 5:46 pm Another thing that's often overlooked on the E85/86 is the wishbones outer joint (to the hub), most cars have a ball joint there but the E85/86 has a rubber joint which mine quite a bit of play in.

I would adjust the steering ring as its simple a free first.

Do you have any more information on this? All the pictures online show a ball joint both at the subframe and hub end with a regular bush at the back, as per the E46 and most other cars.

Bad_Pritt · Post by **Bad_Pritt** » Fri Sep 07, 2018 6:09 am

road warrior wrote: ↑Thu Sep 06, 2018 7:44 pm the rubber joint you speak of, is that no 8 ?

No, number 2 in the second diagram

Bad_Pritt · Post by **Bad_Pritt** » Fri Sep 07, 2018 6:14 am

So, I replaced the droplinks, wishbones and stabilizer rubbers. I got an alignment and turns out that the tie rods have quite a bit of play. So I ordered a set of those after all. The steering definitely improved, but it’s not as sharp as I’d like it to be. I’ll keep you posted on the progress

Markos_Z4 · Post by **Markos_Z4** » Sun Sep 09, 2018 12:22 am

what wheel size do you have at the front ?

my z4 has 140K KM i have 9J wheels at the front . . .
i change all the parts on the pic my steering feels like brand new right now
best thing i change was the swaybar front rubbers with Powerflex polyurethane bushings

my z4 was all over the place on the highway . . . now i can drive with no hands on the steering wheel
if i turn right and take my hands of the steering wheel , the steering wheel will go automatic returned to center point

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Bad_Pritt · Post by **Bad_Pritt** » Sun Sep 09, 2018 7:05 am

I’m running 8,5 in the front and 9,5 at the rear I think

road warrior · Post by **road warrior** » Fri Sep 28, 2018 9:29 am

So looked for the no2 rubber you spoke of, sadly as 2.0 slugs are not deemed worthy of that. Is That good news or bad I wonder

Billbob · Post by **Billbob** » Fri Sep 28, 2018 11:14 am

Talk to the guy at Z shed in Earlstown near Warrington he can sort the sticky steering, he is brilliant .

Jembo · Post by **Jembo** » Fri Sep 28, 2018 11:29 am

You should also try driving a //M. Spent a fortune on all of the above on my old 3.0 which sorted loads out, yet the first drive with the //m’s hydrologic steering is a revelation.

Have come to the conclusion you can get the elec version quite well sorted with time & money, though there’s no substitute for hydrolics

exdos · Post by **exdos** » Fri Sep 28, 2018 11:33 am

If all the parts are fitted properly and in good condition, then your problem is likely to be the geometry causing the issue.

If the front -ve camber has been increased (pulling the pins on the front top mounts) then this will make bump steer more likely. Likewise, if you have any amount of toe out (adjusted on the tie rods) this will make the steering very twitchy indeed. Hope this helps.

Bad_Pritt · Post by **Bad_Pritt** » Fri Sep 28, 2018 12:17 pm

In the meantime I have replaced tie rods and all other mentioned parts, getting it aligned again soon, but already loads better

road warrior · Post by **road warrior** » Sat Sep 29, 2018 7:48 pm

Vis a vis toe in/out situation I wonder if I had it set toe in a bit it might stop the twitchy ness a bit?

exdos · Post by **exdos** » Sun Sep 30, 2018 9:19 am

road warrior wrote: ↑Sat Sep 29, 2018 7:48 pm Vis a vis toe in/out situation I wonder if I had it set toe in a bit it might stop the twitchy ness a bit?

If you have toe-in, when the steering is set to drive straight ahead, then both the front wheels are set to roll to a point which converges at some place in front of the car, which might be as far away as infinity. However, if you have toe-out, then the front wheels are set to roll divergently, and both wheels are trying to turn away from each other in opposite directions, and the moment the steering is turned in either direction, the inside wheel is already on a turning path, which makes the car change direction instantly. Therefore, increasing toe-in makes the car inherently more stable for driving straight ahead but adds "scrub" to the tyres which increases rolling resistance and tyre wear but you don't want toe-out on a road car.

Z4Tuga · Post by **Z4Tuga** » Sun Oct 28, 2018 3:19 pm

I'm also experiencing this problem, intermittently though. When I first got the car I noticed this immediately driving home on the M5 but then for the first 2 or 3 weeks it was in and out of the dealership to sort some other little things so never got the time to get around it. As soon as I had the opportunity to drive it on the motorway again I made sure the tire pressure was right and one thing I noticed was that the left side had less 0.5 bar (was at 1.5). Pumped both tyres up to 2.0 and the problem seemed to go away. Could easily go up to 100mph without any play on the steering wheel. A couple of days later though, back on the motorway the problem seemed to have returned. Checked tire pressure again and the left tire had lost 0.2 bars. This was in the space of a week. Please bear in mind that I haven`t yet done any work on the front suspension, not even balancing or alignment, and the tires on the car seem to be a budget brand, although fairly new. My question is, would such a small variation in tire pressure be enough to cause this issue? Also, is this a normal loss of pressure in such a short period of time or could I be looking at a small puncture?

Bad_Pritt · Post by **Bad_Pritt** » Sun Oct 28, 2018 7:13 pm

Doesn't seem like a normal loss of pressure at all, these are sportscars and should be able to take some abuse. Quality of tyres obviously will always affect quality of the ride. But you should also look at how the tyres are worn because that could be an indication of bad balancing of tyres and or bad alignment. Never a bad idea to have both of those checked out as that's relatively cheap as well.

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