Steering slop help! Slop in rack? Airbag vs Non-Airbag Knuckle differences?

[itsonlygeorge]

I've been chasing a loose steering/drift and have replaced everything I can get at and there is still a measurable looseness in the steering. Right now the car will pull to the right under acceleration and then pull back towards left when letting off the throttle. I have done some research and am replacing the RTABs with AKG poly since the Garagistic ones I installed a few years back are 80A and might be worn out by now after a few cross country road trips with a loaded down car (ski gear is heavy). I am hoping that it's not a bent trailing arm and that it can be adjusted out with the upgraded subframe I am planning to install this weekend.

With the steering wheel locked there is movement when shaking at 3/9 o'clock. Movement appear to be coming from inner-tie rods but you can see the rack and steering column rotate. None of the u-joints in the steering column are loose, however the lower one has a tiny bit of play if you really try to rotate it. This play was what I was trying to eliminate when replacing the rack last year. It was the same amount of play with the old rack after swapping it out.

I took it to an alignment shop (Tire Warehouse) and they think its the tie-rods which are only about 1 year old. They also believe that it could be from the sway bar bushings or sway bar end-links causing it to bind.


- new e36 rack doctor rack with new e36 tie-rods (inner came with rack, installed last fall)
- checked poly FCAB bushings (look good, getting replaced with treehouse soon)
- checked the control arm ball joints (no play)
- checked steering column for play (could be lower u-joint?)
- checked steering wheel and retightened nut (helped?)
- steering guibo is AKG poly (5 yrs old)
- new swaybar endlinks (OEM)
- PS delete kit

Are the steering knuckle/u-joints interchangeable between airbag/non-airbag cars? What else have I missed?

I think mine is a bit loose and I am not sure if the airbag version is the same part as what I have. I have changed every other part on the steering system and I have a sneaking suspicion its either the u-joint (even though there is no real play and the u joint feels tight) or its the lock-pin under the steering wheel being loose?

[scabzzzz]

how did you check the control arms and tie rods? Even if its new, remove it from your mind that its impossible for them to be bad already. Tighten the nuts on everything as well and make sure its all pre-loaded before you tighten.

not sure on the u-joints honestly. go reference them on realoem.com and see if the part number is interchangable with an air bag car and non-airbag car.

[Zambuzan]

I have done some research and am replacing the RTABs with AKG poly since the Garagistic ones I installed a few years back are 80A and might be worn out by now after a few cross country road trips with a loaded down car (ski gear is heavy).

Dang you think they'd wear that quick? And from the AKG website it seems that they only sell rtabs in 75D, which sounds brutal on a street car.

[itsonlygeorge]

how did you check the control arms and tie rods? Even if its new, remove it from your mind that its impossible for them to be bad already. Tighten the nuts on everything as well and make sure its all pre-loaded before you tighten.

not sure on the u-joints honestly. go reference them on realoem.com and see if the part number is interchangable with an air bag car and non-airbag car.

Shop checked them by getting the car in the air and moving wheel. I did same at home and had one wheel on the ground and had someone hold the steering wheel. I didn't see any movement in the outer tie rods or control arms. It looks like its internal to the rack or the inner joints. I will recheck. I have a new set of Lemforder inners that I will likely replace them with.

Zambuzan[/URL][/B]"]Dang you think they'd wear that quick? And from the AKG website it seems that they only sell rtabs in 75D, which sounds brutal on a street car.

Yea. I am curious about this as well. My sub frame mounts are the softer AKG poly so hopefully that softens things up a bit. I just didn't want to order the garagistic bushings again, I had to trim them to fit and I wasn't impressed with fitment.

Condor makes 68D RTABs but they are Delrin and apparently that eventually deforms. I wanted to get the Powerflex 95A bushings but those are super pricy. There are some other brands like IE, and CA Tuned that have RTABs as well but they look cheap and theres no specs on hardness or anything.

[Zambuzan]

Hm, might have to reconsider getting Garagistic 80a subframe riser bushings + rtabs. I haven’t read any long-term reviews about these products.
What did you have trim on the Garagistic bushings?
I think if AKG make 85a rtabs that would be perfect. Other options are Powerflex and IE which are well-established.... not sure what you mean when you say the IE stuff looks cheap tho. IE was one of the first in the market, and have had great reputation.

[varg]

Condor makes 68D RTABs but they are Delrin and apparently that eventually deforms.

FWIW, to my knowledge, and from what they say on their site, they are UHMW Polyethylene. This is a very different material from Delrin, and I have yet to hear of anyone having issues with them deforming. Feel free to elaborate.

CABs have minimal impact on NVH in my experience. They also are not as prone to squeaking if you buy poly unlike the TABs.I have poly in mine, they have rotated in the housings a couple of times and I have considered buying Condor bushings to replace them.

[itsonlygeorge]

Hm, might have to reconsider getting Garagistic 80a subframe riser bushings + rtabs. I haven’t read any long-term reviews about these products.
What did you have trim on the Garagistic bushings?
I think if AKG make 85a rtabs that would be perfect. Other options are Powerflex and IE which are well-established.... not sure what you mean when you say the IE stuff looks cheap tho. IE was one of the first in the market, and have had great reputation.

There was a small ridge on one of the bushings that didn't allow it to fit right in the sub frame slot. I have not taken the sub frame out yet to take a look but I feel the backend move when I accelerate/decelerate and it's messing with the steering. I think those bushings just got worn out. They've been in there for about 4 years of country driving with a loaded down car. I have been happy with the garagistic bushings overall, not to bash their product or anything.

[itsonlygeorge]

I made a quick video of the rack/knuckles before I removed the subframe. The U-joints move easily and do not click or have any flat spots, i cant feel any real play in the assembly. As you can see the inner tie rods don't budge at all. You can see the column turn a bit when its locked due to the locking pin in the column.

https://i.imgur.com/IMkOXgZ.mp4

https://i.imgur.com/cotW7f9.mp4

Should I calll RackDoctor and warrenty the rack?

[jbontke]

That looks like a bad rack. You shouldnt have that up/down movement in the part that connects to the inner tie rod bushing.

[itsonlygeorge]

That looks like a bad rack. You shouldnt have that up/down movement in the part that connects to the inner tie rod bushing.

I am getting a new rack shipped out under warranty. I spoke to rackdoctor and they said its normal to see up/down movement on the drivers side of the rack because it's close to the worm gear which is unsupported. Seems like shittty design on BMWs part. If there's no slop in the steering knuckles, and there's no squeak/bearing issue in the column, and the tie-rods are good, and the poly flex disk has no signs of cracks or deformation, what else is there to go bad? My sanity?

[jbontke]

I am getting a new rack shipped out under warranty. I spoke to rackdoctor and they said its normal to see up/down movement on the drivers side of the rack because it's close to the worm gear which is unsupported. Seems like shittty design on BMWs part. If there's no slop in the steering knuckles, and there's no squeak/bearing issue in the column, and the tie-rods are good, and the poly flex disk has no signs of cracks or deformation, what else is there to go bad? My sanity?

That's really interesting, I am going to have to look at both of my cars and see if they have the same amount of slop.

[zaq123]

https://i.imgur.com/cotW7f9.mp4

Should I calll RackDoctor and warrenty the rack?

Why your whole rack is moving around (second vid). Cracked subframe? could be the issue. Both of my z3 and 325i rack gear has no such up/down play. Also your rear suspension can affect the way your car tracks, bad rear subframe bushings? That would explain accel/decel difference...another thing to consider maybe

[itsonlygeorge]

Front subframe is good. Just took it out to clean/paint. RTABs were rusted up and impossible stuck on the bolts. I had to burn them out. Subframe bushings were good but the silicone had dried up into a solid chunk. Turns out the shock mounts were toast and so were the shocks. That was probably the source of the tracing issue. I have another rack in the way. I’ll install on Wednesday and post up a comparison. Sent from my iPhone using Tapatalk

[zaq123]

Front subframe is good. Just took it out to clean/paint. RTABs were rusted up and impossible stuck on the bolts. I had to burn them out. Subframe bushings were good but the silicone had dried up into a solid chunk. Turns out the shock mounts were toast and so were the shocks. That was probably the source of the tracing issue. I have another rack in the way. I’ll install on Wednesday and post up a comparison. Sent from my iPhone using Tapatalk

Still doesn’t make any sense why the whole rack was moving in the second vid....bolts weren’t tightened?? Sent from my iPhone using Tapatalk

[itsonlygeorge]

Still doesn’t make any sense why the whole rack was moving in the second vid....bolts weren’t tightened?? Sent from my iPhone using Tapatalk

Yes. The rack was just sitting in the frame with the bolts for this video. Sent from my iPhone using Tapatalk