So, what kind of life should you expect from the OEM rubber control arm bushings? I was at the dealership today getting a warranty replacement motor mount on my '06 JCW, and the technician also noticed that both control arm bushings were bad.

As I only have 17K miles on the clock, I guess I am a little skeptical that they were really bad. I did not see any cracks in the rubber, and I did not feel any clunking or anything. Of course driving habits and roads will be a significant factor in life, but 17K miles seemed short, even if under the worst conditions.

I am wondering if the tech just need to fill an hour of work as the service area was not doing too much? I dunno.

On the other hand, since it was free and I had the time.....I don't mind the new bushings, it sure can't hurt.

 

Mine started showing some play at about 60k.

 

60K.......I can readily believe.

 

I noticed mine were out around 52k miles and finally got them replaced (with Alta PSRS) 5k miles later. On my buddy's 05' MCS, they went out at 40k miles.

 

mine were ~37k
i supposed your driving environment affects it?
like how often you autoX/track?

 

The road conditions in the Austin area decent. A few road trips, but definitely very decent overall.
My driving is often spirited, and only one track day so again, I am doubting they were really bad. Also, I was initially concerned that my experience was typical, and not wanting to replace them every 15-20K.

Given the feedback so far, I should expect to get at least 40K on the OEM bushings, so I definitely do not have anything to worry about for some time.

Thanks.............

 

On the other hand, they are worth replacing with urethane even if they are still usable. The improvement from doing so is well worth the effort.

 

I’ve seen a leaking bushing in the box so sometimes they are doomed from the start and one didn’t last a few thousand miles, but mine normally last between 20-30k. Recently, I replaced a pair on an out-of-warranty MINI the service department said were bad, I could see they had no evidence of tears, but the owner wanted them replaced anyway; the bushings were healthy after all. New rubber always feels good.

 

Wouldn't the urethane deliver more NVH ? I thought you were a low noise advocate?

Are the urethane bushings that much better than OEM style such that the extra NVH is acceptable even for you?

 

I am a hawk about NVH - I've tried urethane in four bushing locations, and taken one of them out for that reason. Urethane isn't really hard, just a bit higher-durometer (firmer) version of the OEM rubber bushings.

The front and rear control-arm bushings work in rotation, rather than compression (like the strut-top bushings do), or something, and they do not transmit much additional nasty. I found the difference minimal in the front control arms, and unnoticeable with the rear helper bushings.

Both of the control arm bushing upgrades make a big difference in the controllability of the car (front ones more so) - much greater precision and less unexpected, non-linear behavior when cornering. Personally, I would not recommend solid (delrin) or heim-type bushings in any part of the car - that's for racer-chasers who don't care about noise.

I removed the urethane replacements from the rear strut-tops, and went back to stock - too much interior plastic noise being excited.

The lower engine mount (torque-mount) transmits a throbbing shudder at idle, especially with A/C on, but I don't commute in the car, so the difference is well worth it to me.

All of one's life is a series of engineering trade-offs...
6^)

 

I am on your bus OldRick, just a series of tradeoffs for sure. I might be interested in urethane for the front lower control arm bushings after all....

BTW, since we are on the subject of these lower control arms................
I, uh........ kind of broke the M12 bolt attaching the ear or tab to the body. There are three bolts total, 2 that are close to each other and positioned vertically, then one which is sort of angled to the rear. Anyway, that one by itself is the bad guy.

Trying to be exacting and precise, I was using my torque wrench to tighten it perfectly to 74 ft-lbs. Well, for some reason the torque wrench did not and would not click on that bolt, I have used it before and after so I know my Craftsman torque wrench is working properly.

I have since heard that the captured nut in the body with the integrated locking mechanism may be the culprit in somehow 'fooling' the torque wrench and effectively preventing the 'click'.

So, now instead of being 5 minutes from completion on a project, I must take a few steps back.

If I am lucky, I can get that damn bolt out, and then get a replacement tomorrow from the nearest MINI dealer, which is 75miles away.

With the new bolt, I think I will skip the torque wrench this time and just go by feel.

 

The bracket to chassis bolt is a TTY one time use @44 ft-lb + 90 degrees, If I re-use the bolt I only do 44 ft-lb. The chassis threads may need to be restored (cross-thread) and bolt replaced (stretched) if you are turning with no stop, or you may luck out if it backs out easy, the bolt threads are ok, and it can accept 44 ft-lb, then just replace it when you can.

 

OK, now I am confused. This is the same bolt utilized for the front mounting point of the TSW X-brace. So, TSW indicates this bolt is reusable and to be torqued to 74 ft-lbs. Also yesterday, I was just at the dealership and the tech just tightened the original bolt with an impact wrench when he was installing the new bushing.

So, does 41 ft-lbs plus 90 deg roughly equal 74 ft-lbs ?? This method may work much better than simply stating 74 ft-lb, as my torque wrench just would not click. I don't know what it is about that damn captured self locking nut????

Also, I can't find ANYTHING remotely resembling torque specs on this bolt in the Bentley. If anybody can tell me where to look that would be most appreciated.

 

Those TTY bolts are one of the reasons I haven't installed my OBX header. Some instructions say you may need to drop the subframe to get the thing in there, I would need to get them from SA also. Now that I mention it, I heard that BMW of Austin is now doing non-warranty MINI work. That means we may be able to get parts from them .

 

In the BMW TIS, Series M' R53 torque specifications section for the front subframe - Bracket, Control Arm, to Body – Joining torque 59NM, Torque Angle 90 +or- 15 degrees. (replace bolt)

I’ve done the same thing, so that’s how I know your situation, it was one of a few reasons I purchased a thread restoration kit.

chuckt, I’ve a suggestion for you to get that header in, remove the front lower heat shield. Contact me if you need details.

Ooops, I mean 44 ft-lbs plus 90 degrees, section 230-12 Bentley Manual Transmission section 2002 - 2004 issue

 

59nm, ok got that, and converts to ~43.5ft-lbs

Torque Angle 90 +or- 15 degrees. (replace bolt), OK, well I am very surprised and I guess disappointed that TSW is specifying to torque this bolt to 74 ft-lbs, that is obviously just wrong! And I will be replacing both, since i have to do the one anyway.

So, what is the BMW TIS, and where can I get alook at it? On line somewhere? Maybe in my Bentley somewhere?

Also, what is a thread restoration kit? Is that just a set of taps?

 

I did some research to see if there was an answer to that question. I looked at some of the old bolts I’ve replaced to see if there was a class designation, but the markings were un-decipherable to my eye. Looked through my Carrol Smith book but nothing there, Google search and this sums it up- “One-time-use, or torque-to-yield (TTY), fasteners take advantage of the torque yield principle. Most torque specifications build in a 25 percent safety margin--they can be overtorqued by 25 percent before damage occurs. TTY bolts do not have this safety zone. They are designed to be tightened just into the yield point but not to the extent that the metal is distorted. The advantage is they deliver 100 percent of their intended strength, versus the 75 percent strength provided by regular bolts. The drawback is that they can only be used one time. Once they are removed from an application, they can no longer support the load they previously did, and they must be replaced with TTY bolts. Installing a conventional fastener in their place will result in a 25 percent weaker clamping force.”

So, in other words, no way to say what is the equivalent torque specification based on this limited search.

The TIS is the service guide for BMW/MINI Techs.

A thread restoration kit consists of taps and dies that can reshape damaged threads, they are not cutting taps & dies. A restoration die would not repair a stretched bolt/thread, but a restoration tap could repair the chassis threads if they had not been stripped. Don't sweat that one just yet, unscrew the bolt and try again, stopping at 44 ft-lb.

 

Thanks for the research and info sharing. I do not believe the threads are stripped in the chassis, but I guess I will find out when I try to remove with the easy-out.

It is disappointing that the dealership did not replace these TTY fasteners yesterday when they replaced the control are bushings. Not to say that was a factor here, that can't really be determined, just saying if they are MINI specified as TTY then the dealership should have replaced them.

Also disappointing that there is no reference to TTY or the torque spec in the Bentley.

One more, it sure would have been nice to get the proper info from vendors selling products that require the removal and replacement of that bolt.

Um, do you really mean 44 ft-lbs 'plus 90 degrees' ? and of course this will be with the new bolts.

 

What is there in a Lower Control Arm Bushing that leaks??

Jim

 

The LCA bushing is fluid filled. https://www.northamericanmotoring.co...a-bushing.html

 

Hey K-huevo,
Thanks for the location in the Bentley, it was on 230-12 in my 02-06 manual, so plenty close enough. BTW, I did manage to easy-out the remainder of that bolt, now I just need two new ones.
Ok, so here is a pic of the bolt still in the chassis: center punched, pilot drilled, and then, 5/32" drilled and ready to accept the easy-out.

And here is a pic of both pieces of that bolt, the longest piece still has the easy-out jammed in it, and then the good one from the other side.

Ugh, I just might have to take another road trip to SA, either that or I am down until early next week.

 

101k miles. Discovered during a tire purchase. I had noticed some vibration at around 90K on my steering wheel

 

Well, shucky-darn! Learn sumpin' new every day!!
Thanks!!

Jim

 

the failure rate of these bushings is very, very wide, as K-huevo said. One guy I know when through three sets in less than 60k miles. Really, this is one of the crappier parts of the car.

For those that are interested in upgrading, besides the options listed already, Bavairian Autosports has both street (softer urathane) and track (offset for increased caster and stiffer urithane) available on clearance now....

Matt

 

Just to clarify.
I may be misunderstanding what you are saying, so forgive if I am. But, the front control arm of the Mini does NOT rotate in the bushing. It "rocks" See my post on the other thread about Madness bushings.

The rear control arm does not pivot on pre '05, maybe '06, not sure when they changed that. It far from pivots and rocks like crazy.

Delrin can NOT be used for either of the bushing, no way, with the exception of the later rear. But I have not seen that in person so I can't comment if in fact it would work there either.