Front Control Arm Bushings Slipping

[Luke]

Hey guys

I'm looking for a solution to solve my front lower control arms slipping backwards on my SE due to hard track braking on sticky wide tyres.

The short form of this long post is:

Original bushings worn out on 2004 SE, front lower control arms sliding back into mounting points under braking.
Removed and cleaned up arms.
Replaced bushings with Energy Suspension Poly, arms went through flanges like butter. No sharp edges noted.
Replaced with Superpro. same deal, but not as bad cutting they are softer so squeezed into the holes.
Replaced with I.L. Motorsport rubber, arms slipping backwards again.
Ideas and Help Please.


The long detailed version:

Earlier this year I decided to change my 13 year old bushings as my front lower control arm bushings were worn out. Rubber was squeezing out of them for a while and I could only get 4.5 degrees of caster.
The lower control arms were banging into their mounting points under braking on the track. There was a noticeable clunk each time I hit the brakes, especially at Sandown at Fanfest.

I already had done the front upper control arms some years earlier with ISC Racing Delrin offset bushings to provide a lot more negative camber. These are still in really good condition so I have not replaced them.

I ended up going with Energy Suspension Power Flex Poly Urethane bushing kit for front and rear.
Installed them some time in March this year.
Removal of the old bushings was fairly easy with some threaded rods and basic hand tools.
The rears actually looked quite good when I removed them, I probably did not need to do them in hindsight.
All the new ES Poly bushings were lubed up as required, ie the whole thing according to the instructions and installed. The only ones I didn't change were the rear upper outer bushings as that required a lot more work to do since it is in the knuckle, not the arm. Plus it looked like new anyway.
The arms installed back in easily and everything was torqued up with the suspension loaded.
Took it for a wheel alignment and was shocked at how much extra caster I gained since the arms were now sitting in their correct spot. I could get up to 7.5 degrees.
Up front I went for 7 degrees, - 3.25 degrees of camber and Zero toe.
At the rear I went for -2.5 degrees camber and +2mm toe out. Yes I know very unconventional, lets just say I like to slide around.

I drove the car out, but the steering felt vague. It did not feel like it wanted to centre. I believe this may have been due to the fact that Poly is not a good material for the lower control arms as it does not allow the lower arms to twist like they are supposed to.
After just one Supsersprint at Wakefield Park my alignment felt way out. The lower front bushings failed the Luke test. See pics below.

Note the rear control arms were perfect.

I got a piss poor response from Energy Suspension via Track dog racing about the failure. Energy suspension did not contact me directly, only through the seller did I get a response. Trackdog were all good about it though.

“…sharp, poorly welded edges are cutting the flanges off the bushing edges. This doesn’t fall under manufacture defect, he will need to buy a new set of bushings. We would also recommend that the arms be replaced or at least cleaned up so that they do not destroy the bushings again.”

Great response. Load of crap since they have never seen or touched my arms and I actually cleaned up and painted the arms before installing these.
I say the product is not fit for purpose. How is a compliant relatively soft material supposed to stop a hard thin steel edge with the weight of a car going through them like butter???? I started seeing why there were people out there that say don't touch Poly on a MX-5 for race use.

After that poor response I decided to try Suprpro on the Rear mounting point with Energy Suspension on the front mounting point.
I lubed up the bushing as per their YouTube Video, so again the whole bushing.
Well the same thing happened which I was not to surprised at but at least I got 3 rounds in this time. SMSP GP, North and Marulan.
There was less cutting as the bushing compressed and went back through the hole. I would say that is due to these being much softer than the ES ones. The ES ones on the front points totally had their flange cut off.


I will say that the Superpro unit looks much better engineered and fits far better though.
And their response about the failure was much more realistic.

the bushes have been designed for street use not racing but in saying that we do have some customers using the bushes in their race cars [Total Parts Plus ] is one of them.
I have given your email to our head engineer he would like to make up a new design set of lower control arm bushes for you to try out.

No new design as of yet but I believe they are still working on it. That response from them was in July.


For my 5th round of the Supersprints at SMSP South circuit the suspension killer I just flipped the Superpro bushing in the rear mount and installed some left over ES ones that were still good in the front point.
I did one thing differently. I only greased the Centre pin and the outer flanges as that is what Nolathane says to do. Not the outer case of the bushing. Sort of makes sense as you would want the bushing to rotate around the pin and stay still in the arm. Plus I thought it may stop the arm sliding through the lip so easily.
This made no bloody difference. I only did 3 sessions and the alignment was stuffed. All 4 bushings had been cut through to some degree. The rights ones were far worse than the left.
I even filed and sanded the lips of the arms this time before installation. They were super smooth.


For round 6 I went back to rubber using I.L Motorsport bushings for the front lower control arms.
Install was much more difficult with a press. Thanks Russell for the use of your press.
The alignment was good afterwards. Same as the earlier one but I went for 6 degrees of caster this time.
The car felt terrific. At Wakefield park I went 0.7s faster!!! 1'08.47
But guess what, I noticed I started having a pull to one side. I did not hit any curbs hard and no wheels off track all day. I needed to steer a bit to the right to go straight on the way home.
The arms have slid back on the bushings!!!!!!!!!
The right is worse than the left.



I have an idea I will try to try to prevent this problem utilising these I.L bushings and the design philosophy of the Poly bushings.
By design philosophy I am referring to that lip the polys use to prevent the arms sliding forwards and back.
The front I.L mounting point bushings have a massive rubber lip on them already so I will leave them as they are.
The rear mounting point I.L bushings have a lot of the centre pin sticking out and a very thin rubber lip so I plan to take advantage of this by installing a large thin washer on this which will butt up against the thin rubber of the bushing lip and the metal of the arm. I will then slice a thin piece of one of the ES poly bushings to insert between the mounting point and washer. I believe this will stop the arms sliding back as the arm will now have a solid surface between the arm and the mounting point. I can't see the arm cutting through steel.

I will have to drill the hole out of the large washers or find some others to fit over the pin so they but up right against the rubber. And somehow slice the poly thin enough to fit between the washer and the mounting point. If I can't slice the poly thin enough I will use a toilet cistern seal. Surely I will be the first toilet sprung MX-5. The poly or toilet cistern rubber seal will be there for noise and compliance. I don't want metal on metal.

If that still fails I guess I will go with new arms.
I can see how this could help with Poly as they are cutting through the lips of them and the new ones may be a lot smoother than mine.
I don't see how this would help with rubber bushings though as they rely on the tension between the rubber and the mount which clearly is not working for me.

I could only find one whole post on the internet about this with rubber ones, which says to go to Poly to prevent sliding.
https://www.miataturbo.net/general-miata-chat-9/why-do-my-control-arms-slide-forward-bushings-94474/


So has anyone ever tried cutting poly urethane nice and thin?
How do you do it?

Also, anyone else have any other ideas or experience with this problem???

[ManiacLachy]

I've never heard of that happening before (of course, that doesn't mean it isn't happening!) That's got to be getting expensive and frustrating for you.

Have you considered delrin bushes?

http://sadfab.com/bushingpackages.html

A really good read on bushes in general:
https://www.miataturbo.net/suspension-brakes-drivetrain-49/miata-bushing-megathread-heirarchy-diy-delrin-dimensions-info-discussion-87573/

[Luke]

Yes I have thought of using Delrin but a bit of reading I have done suggests not to use them in the lower control arms for the same reason as poly. Binding.
No problems with my Delrin ones in the upper arms
Even some of the suppliers say to use heim joints and not delrin on the lowers.

[flyingdave]

Have you measured the arms and compared them with each other (or another arm)? This would tell you if the arms are bent. Also does the location of the chassis mounts match the arms?

[Tony]

Luke,

If you can get something like these in the right size they may be a better alternative to the cistern washer!



How much lube are you putting on the rubber bushes when you press them in? Could that be a reason they are sliding within the arm housing? I've only ever used mildy soapy water and haven't had any move yet - touch wood.

[greenMachine]

Luke, a few thoughts.

You won't slice poly easily, if at all, not a nice clean cut. Try freezing it, I hear that helps but the word I see is that it is not going to work. I have some that I hacksawed off you are welcome to.

I wouldn't sweat the steel-on-steel thing, at least as a temporary measure; just make sure that its bore is greater than the steel pin diameter, and it is sitting on the steel pin loosely. Its function would be to prevent the lateral movement of the arm, ideally there would be two of them (one on each LCA-I location).

Lube. Don't. Just don't. When we (don't hate me, I was young and stupid :oops: ) put the superpros in the original GM, we used carby cleaner (I think), just a light spray, just enough to moisten them and then rushed the fit before it all evaporated. I would NEVER grease the outer surface where it mates with the suspension arm. THIS IS NOT MEANT TO MOVE in the bushing housing, so wtf are people putting lube in there ? The only movement is supposed to be between the pin (held solidly by the suspension mounting bolts to the frame), and the inner bore of the bushing - this is where you lube. If you have lubed the outer surface of the bush, I am not surprised the bush is moving relative to the arm - rubber or poly.

Screws. I use screws (including a grease nipple) to locate my delrin bushes. Mainly on offset bushes, but still ... This will probably not work on poly because, well, poly.

Delrin. Delrin rocks. Racers use delrin, ricers use poly. I have contributed to the megathread and/or the Sadfab review thread fwiw, and I am a believer! Luke, you are out-driving a second-rate product - get with the real stuff, you will only be kicking yourself for not doing it earlier.

[Luke]

Dave out of curiosity what would bent arms have to do with them sliding on the bushings? I could understand alignment issues but my car aligns all good.
The arms centre perfectly when installed relative to the mounting points. Even gaps each side. The alignment bolts are almost in the same position on each side to achieve the same angles. So I'd say they are not bent based on that.
No other arms to compare them to.

Tony, we used some high quality home brand dish washing liquid on the rubber. Just smeared on by hand. The though of the liquid causing the slip has crossed my mind, but the bushings didn't exactly go in that easy.

In the upper Delrin offset bushings I actually have grub screws holding them in place to stop them rotating. That has held them in place for several years now.
I have though about doing this for the lowers, but I gather the rubber will rip up in no time as would Poly bushings.

[greenMachine]

If you MUST use poly, think about the SADFAB poly-bronze. I have a set to go in the SE, not yet fitted so I can't do a review yet.

You already have the Energy bushings, which I think are the bushing used (also Prothane), so all you would need is the sleeves and pins.

[Luke]

Heres why I put lube in the Polys on the outside.
https://www.youtube.com/watch?v=Wvk9j6CgRI4
Manufacturer said to. Also said it on the paper instructions.
Energy Suspension guide in the box also said to.

A similar video from Nolathane, says do not put on the outside.
That made sense to me, but I didn't see that Video until I had a third attempt of using Poly.
I tried utilising a combination of what I had left without greasing the outside at the third attempt on Polys but the arms still went through the lips anyway hence why I got the I.L Motorsport rubber ones for attempt number 4.

I would not say I already have ES bushings for the front lower control arms. The Poly is all stuffed. The only thing good is the centre pins.
I'm not having any problems with the rears yet though. So they could be upgraded later if required.

I'm sure I have found that Sadfab website through google before whilst looking up solutions to this problem.
The Sphericals kept scaring me off but after reading a bit more now I realise I do not need the sphericals.
Reading through the info you need one Delrin and one compliant moving bushing for the front lower control arm.
I do not really want to go down the spherical path as it is still a road car, not a race car.
The guide suggests I should use the I.L. rubber bushing at the rear Caster Adjustment and Delrin for the front camber one.
But that is only based on the fact you may want an offset one for camber. I will review if their is any damage to my I.L ones before deciding which Delrin one to buy. I would prefer the caster one as the I.L rubber Camber one has a big lip on it to help prevent sliding of the arm.
I would hope that my arms would not go through the Delrin.

I do like that they show pics in the thread about rubbers ones just sliding in the arms. So I'm not the only one at least.
They have all the measurements for the arms and mounting points for me to compare mine with as well.

I will try my washer idea as a temp fix for the remaining supersprint and look at getting a Delrin bushing for the FLCA front position.

[Dean.H]

I had the same problem.

I am pretty sure the arm was rotating around the bush, not around the steel inner sleeve. I know you followed the instructions for greasing prior to installation but that is part of the problem as it makes it easier for the arms to rotate around the bush rather the bush around the inner sleeve.

I put in new poly bushes and pinned each bush with one grease fitting and two button head hex screws. Problem solved.

[greenMachine]

Yes, I know that is what they say. But that doesn't make sense (to me at least), and it is not (in my experience) necessary anyway. Your experience is consistent with what my common sense ( ) tells me. Some lube may help, but I would use a carefully selected one, preferably one that evaporates, and the absolute minimum at that. From memory, the ES-based poly-bronze in the FLCA-I castor-compliance position (not camber) in the racecar did not require any lube.

I used the Sadfab RUCA-O spherical in the racecar, tricky to install but otherwise NBD. I agree, a full spherical setup would be overkill in a road-registered car. Not to mention exxy

My SE is getting the clutch checked out next week, then going into the shop for ECU and other mods. Then I will do the bushings with the Sadfab poly-bronze. I have a couple of sets of spare arms, I might even start on them early. I don't usually do write-ups, but maybe for this ...

[NitroDann]

The lube goes between the centre tube and the Bush not between the Bush and the arm.

Dann

[Luke]

Seriously Dann
You had to get your 2c in didn't you.
We have been through this already. Even in Post 1.

To shorten it up for you regarding Poly Bushing failing on FLCA.
Following instructions I greased the outside as well as inside and flanges. Result of Failure, twice.
Didn't grease outside, only inside and flanges. Same result of Failure.
I don't see how 3-4mm of soft material has any hope of holding back a 2mm edge of steel with large forces going through it.
Would be fine for a road car, but hopeless for a track car going over ripple strips while braking.

Rubber was better. Arms slipped back, but less than Poly. I may have a self inflicted wound by using Dishwashing liquid to help aid getting them in here. When I try my temporary washer method to reduce the sliding I will wash them out.

[NitroDann]

I see photos of a part which is supposed to stay in place using only friction absolutely slathered in Grease.

After this a mention of not adding grease but not mention of how the surfaces were being prepared.

I don't know what else to say. Probably millions of cars worldwide use polyurethane bushes with success.

Friction holds the Bush in the arm, the adjustment bolt clamps the sleeve bush still when its tightened and the grease goes between the sleeve and the Bush and between the Bush lip and the subframe as those are the only place is which are supposed to be able to move.

Dann

[Luke]

I still don't see where you are going with this as you are just saying what I already said regarding fitting of them.
The picture with the grease spewing out on the bench is the 2nd attempt using Superpro following their instructions.

To clear it up I did not put pics up of the 3rd failure when using no grease on the outside of the bushing. And yes I did clean the existing grease out first.
The end result looks exactly the same as the first 2 failures when I did have grease on the outside. Steel arm went through the lip under high loads.

Quote of myself from my first post to save finding the part where I already mentioned this.

I did one thing differently. I only greased the Centre pin and the outer flanges as that is what Nolathane says to do. Not the outer case of the bushing. Sort of makes sense as you would want the bushing to rotate around the pin and stay still in the arm. Plus I thought it may stop the arm sliding through the lip so easily.
This made no bloody difference. I only did 3 sessions and the alignment was stuffed. All 4 bushings had been cut through to some degree. The rights ones were far worse than the left.
I even filed and sanded the lips of the arms this time before installation. They were super smooth.

It didn't slide over the lip on the ES ones. It cut through the things.
Superpros got squashed inside the mounting point as they were softer.

And something more interesting, even when I did have grease on the outside, they came out almost dry, like it all got squeezed out. Even the inside does not retain much in the slots. We are talking a couple 100kms of use here. According to ES marketing the grease is super special awesome tacky grease and doesn't run out so easily.
Superpro grease just looks like normal silicon grease but it does stay better inside because of their diamond pattern in the Bushing.
Either way both do not work for me on the track. Plus they both ruined the steering feel compared to rubber.