Sway bar bushing issue
 

Hello internet. I feel like I messed something up with my sway bar install. Installed a Perrin 19mm front bar, after having greased the crap out of the inside of the supplied bushings and everything is torqued to spec. But now, before installing endlinks I cannot physically rotate the bar in the bushings.

Yes, I know car forces are way more than my wee little arms can generate, but I was quite easily able to rotate the OEM bar once the end links were disconnected and I wouldn't think this should be 5x or more greater force needed.

Any ideas on what could have gone wrong? Is this normal?

I have no experience on this brand of bars but I’ve tried all the whiteline ones on both front and rear and they were all the same, when installed the bar cannot rotate as freely as the oem one. This should make the bar stiffer and the solution is using a washer or two to relieve some pressure on the bushing, keeping the holding bracket a tad higher basically.
I did this on my rear 16mm whiteline solid bar and it worked, I haven’t done the same for the front cause I wanted it stiff and solid so it didn’t bother me at all.

Upon further research, the search term for this seems to be "sway bar binding". Knowing that leads to finding videos/articles that say shimming with washers is a common solution.

Apparently it should not be difficult at all to rotate the bar.

Interesting that their bushing is so undersized. Might be too late now, but do you know the ID of the bushing? Or is it an issue of the bushing external shape that gets too compressed by the bracket?
I experimented with a Whiteline 14mm rear bushing with the 15mm 2017+ OEM sway bar and it still rotated freely (the bar did bind after a few months, presumably as the grease was forced out).
I'm also using Whiteline 18mm front bushings with the OEM bar and it rotates freely.

Nah, I just assumed the kit would just work and put it all together. I don't think getting any measurements from the unclamped bushing would be of any value anyway. I will say that I recall it being a bit tight before torquing the bolts to spec but I assumed that's because the grease was so sticky.

Took a measurement of the Perrin bushings and stock bushings unclamped. The Perrin bushings are about 3mm taller than the stock ones, and being poly probably will compress less than the oen rubber.

This happens to be precisely the thickness of one of the Whiteline endlink heavy duty washers, but I should probably use those on the end links like I'm supposed to lol. Washer hunting I go...

...

Found two regular sized washers to shim with that combine to 3mm thickness. I'll see how that goes. Other options include one or two larger washers 2mm thick each. If anyone has had a bad experience with shiming this way, let me know so I don't break stuff?

Update: 1.5mm shim on the stud and 3.8mm shim on the bolt seems to have made it better. Still not great.

I think the bar might be too short or warped somehow and that's causing weird angles with the bushing on the curved bits. There's about 1/4 inch of play side to side and at a very specific point the bar rotates easily, though it is inconsistent. Grrr.

Likely designed to need some break in, worth emailing Perrin tech support iirc they’re decent.

I've had the Perrin 19mm sway bar before but didn't run into this issue. @strat61caster is right the first step is to contact customer support and hopefully get them to send you replacement bushings. You absolutely do want the bar to freely articulate up and down. I personally wouldn't run bar bracket spacers...I think you'll find a way to free up the bar without them.

I don't think it would be a problem installing 20mm bushings if that didn't work out.

Also, when you applied ze lube did you lube just the inner portion of the bushing, or did you also do it on the bar itself where the bushing sits? I like to include the bar as a place to lube since grease may be squeezed out of the bushing when slipping it on, especially when the hole is small diameter relative to the whole bushing.

Update on this. After communicating with Perrin technical support, the conclusion is that the bar is within spec but the bushings are too tight and likely out of spec. They are going to send me new bushings. It seems they may have gotten a bad batch so it might take some time.

Other points of note from Perrin support if anyone is troubleshooting a similar issue and finds this:
-Bushings should allow for easy actuation of the bar without shimming clamps.
-There may be some break-in that normally occurs with the bushings, but it should not be difficult to actuate at first.
-1/4" of gap between the bar stops and bushings is within specification.
-Bar thickness measured at 19.15mm is within specification
-It appears that I did not mess up the installation, but installing the bar upside down has caused strange issues in the past.

I think my front bar has the same issue. I disconnected the endlinks and the ever present jiggle in my front end disappeared, and the suspension felt like it was working incredibly much better / smoother. I got under the car, and with one hand on each end of the bar and pulling down, I actually lifted my upper body off the creeper before the swaybar rotated. ��

The bushings definitely fill the bracket way more than the stock ones, and stick out past the surface where it mounts to the car.

Is there someone in particlar I should speak with at Perrin?

-Mike

@Spuds Did you ever get this resolved? I’m having the same issue on my 25mm Eibach front bar. The bushings are 25.4mm ID and according to Eibach they are designed with “crush” in them. They advised the bar being tough to move is normal but from my research that answer just didn’t sit right so I started looking into it and came across this thread.

I haven’t had a chance to disconnect one endlink to see if there is any change yet.

Yes, I guess I forgot to come back and update this. Perrin sent me a new set of bushings and it was much better. Still had some resistance as I recall but wasn't impossible to move.

Edit: Text from my build thread:
"Perrin sent me new sway bar bushings last week, but forgot the lube. Got some from Amazon and finally got around to installing them. On measuring them, the hole seems to be about 0.1mm larger in diameter, though the bushings are about 1mm taller . Definitely better than before once assembled with no shims but still a bit more resistance than I'd expect. I added a 2mm shim to the clamp on each side and called it good enough. I'll check it again after driving a bit. No pics of this one."

Thanks for the follow up Spuds. I'm going to try shimming the sway bar bushing bracket to subframe connection to reduce the bind. The only other 25mm bushings I could find for our cars cost $60 so I figured trying out some spare washers from my box is worth a shot first.

I also discovered that my Eibach bar(set to stiff) is hitting the lower control arms on both sides. Stock length end links dropped on TRD springs(.75" drop). Really didn't expect to have this issue with the mild drop but here we are.

Wild to feel the steering bind so much that the steering wheel is bouncing back towards the center when the wheels are in the air.

I ordered up some Whiteline KLC179 front end links from Amazon and will redo the bar install with property set up end links. Install video for reference : https://www.youtube.com/watch?v=yNZ6AJhJmVY

I'm going to have to check mine when I get it out of storage again. I have the Perrin 19mm and I don't recall trying to rotate the bar just sitting there or having any issues with it. In fact, I really didn't notice any major change with it even on the stiffer setting (~70% stiffer) for autocross.

I do know mine has this weight issue on the passenger side of just contacting the control arm now that I have RCE SS-1 coilovers. Looked like it was more about the material on the ends and how the two adjustable holes were positioned. With a stock bar and one mounting point, it would clear no problem.

Something tells me things are sitting 100% right or something. I am using the stock swaybar endlinks again as the Perrin ones I had contact the chassis with -4 degrees of camber. They're simply too thick at the attachment points. A bummer because in street class trim (aka stock-ish) they worked and held together great with no noises or issues. Even with the coilovers they were fine until I added the camber for racecar purposes.

I went ahead redid the install. I shimmed the sway bar bushing brackets with 1 small washer(I'll report back with the washer thickness) at all four bolts/studs which allowed the bar to rotate much more freely. It still takes a little effort to rotate but nothing significant enough to cause bind IMO.

I resolved the sway bar to FLCA contact. I didn't have a lift or blocks to place under the wheels to get the entire weight of the car down but did my best to simulate it using a jack under the FLCA. The jack wasn't able to compress the front end enough to achieve the same center of hub to fender measurement as if the car was on the ground with the cars full weight but it was somewhat close at roughly 14" vs 14.75".

In an effort to get the bar end as horizontal as possible I may have inadvertently shortened the new links too much. Sway bar clearance with the body of the car under compression(at the top of the sway bars arch) looks to be a little tight so I may need to go in and lengthen the links. Planning to apply some painters tape and put some miles on it investigate further.

I haven't gotten a chance to really drive it after the reinstall but from my limited 5min test drive, suspension binding appears to have been greatly reduced, the noise from the FLCA contact is gone, and it feels like the car tramlines much less(I had none with the same alignment and stock from sway bar/links).

Having similar issues with the RCE 20mm front sway bar. Just removed and will shim and test. Also, noticed that the 22brz has some extra reinforcement on the area, will take pictures after reinstall