lowered tire pressure another 2psi back to my summer setting at 33.5psi and
found the car is still well planted. no need for dampers yet.
last week it was close to 92F and that caused my 'Spring' psi setting
to be too high for those 2-3 days that I did not change (lazyness)
cause i knew the temp would drop back down 15F this week.

so, im still happy with the stock dampers.

 

OK...

Last night we had some time to really study the movement of this trailing arm bushing. What we discovered is in fact that my first post here is wrong, and loosening the bolt will do pretty much nothing.
Sorry to those who have taken this advise, I hope it did not cost you $$ to have it done.
I have some video that we took of the motion in this bushing. Not sure how they turned out, but I will post them here later. It's not a pretty sight...

Again, sorry for the mis-information. I felt it was important to let you all know that I screwed up on this , .... not the first time ..

 

Well, you put the info out there in good faith...and that's how it should be taken.

 

to you onasled. You are generous with your experience and have proven yourself human. Join the club. It was something worth sharing, and hopefully all people are out is a little time up on an alignment hoist. I always enjoy time under my MINI (MINIs on top, I always say!) so it's not all wasted.

cheers,

 

cool. I was kinda skeptical from the beginning, but thanks
for letting us know. trial and error is key for tuning.


talking about mistakes, i typed on my earlier posts that my rear
swaybar size was 19mm.. it's 22mm on the firm setting. so, i
fixed that up today.

 

for having enough self confidence and principles to own up you're better than schumacher in my book. no matter how many races and titles he wins, he's still a great driver, but a lying, cheating, scum i wouldn't lift a beer with...so does this mean you're buying????

 

We all mess up. Admitting it is the cool part.
All the good info you provide far outweighs one little goof.

 

Here is a very crude video of the bushing in action. I forgot to mention on the video that the car is upside down. Don't have your volume up to much as the audio is annoying. VIDEO
Just to note that in the Bentley, or maybe in the other manual it dose state that when replacing these bushings that the bolt should not be tightened until the suspension is fully loaded. So, it does make a difference, but I would have to say that for lowering a car it would not be a noticeable one in any way.

Finding the pivot point of the traling arm is tough.

 

For the early version of the trailing arm (Bentley manual), the end bolt is at its most perpendicular position with the bushing when the trailing arm is under load. I would assume applying torque at this point would ensure limited side loading which can cause undo shear stress to the bolt.

 

kudos to you mate, i'm sure no-one cares that you made a mistake. You thought it did the car good, and you didn't hoard your findings, but shared them with us. We're all grateful.

So after i get springs installed, what do you recommend i do besides align all four wheels? What about what 62lincoln's alignment guy said, he agreed with you

 

Because it's kind of a logical assumption to do this. In looking at the later bushings, post '03 I believe, it appears that this might have more of an effect. The motion of these '03 bushings is odd to say the least, but what do I know about comfort. I believed the rubber bushings to be much stiffer and was a bit surprised to see just how soft and mushy the actually are.
There is obviously something to the fact that this 'not tightening the bolt until the suspension is fully loaded' is recommended by the manuals in reassembly.

I'll be checking out some new "solid" bushings next week and will report on them at some point. Otherwise we are looking at a complete refab of a new trailing arm pick-up point. Possibly a hiem or a spherical.

Added this:
I still do feel that if you have the oportunity to do this step to go ahead and do it. There will be some slight preload released when doing so. It's just not near the amount that I had thought.

 

I've always said it's a good idea, just makes sense to me. Did you get my PM by the way?

 

You mean the anti-bear one....

 

i have an 05, so i think i still might do this...

 

I was just in for an alignment and requested that they loosen the trailing arm bushing bolt as you suggested, bounce the car around a bit, and then tighten it again. The tech said that the left camber changed by .3deg and the right camber by .1deg.

 

Hmmm, so now what? I may as well do this when I do all four rear control arms, probably at MINIs on the Mountains coming up. . .

I have read all the posts, and I probably wouldn't do this if I wasn't already going to be under there, or have someone more qualified under there , but. . .

Should this be done on both the front and rear trailing arms?

 

Can't do it on the fronts as those bushings are a different setup.
It's really an easy thing to do on the rears so I would say to go for it. Anyone using poly inserts should absolutly do it.

 

The front control arm bushing is different than the rear. The control arm pivot shaft has a six sided shape that fits into a corresponding bushing. In order to do the same type of loosening, the control arm would have to be removed, the bushing sleeve pressed (actually pulled) out, and then pressed back, in a different orientation.

If you are very concerned with pre-load on the front control arm bushing then change to polyurethane bushings. However, the stock bushing provides just a little more cushion for street use. Take a look in my gallery for some pictures of the arm plus the sleeve & bushing removed and you’ll get an idea of the shape. BTW, the bushing and sleeve are one part; the separate bushing shown is damaged.

In my opinion, pre-load on the front control arm from moderate lowering is not a great concern, but lowering an inch or more puts extra stress on the bushing because it will be twisted most of the time.

 

Changing to poly bushings would be nice, but what kind of job would that be? pricey, right?

 

$1,200, the cost for me to have a BMW/Mini dealership perform the work - that also included replacing all for ball joints and tie rods as well...while they were accessible. Some Mini deslerships will not perform aftermarket work.

In the end, K-huevo did it right; he removed the axles and not the sub-frame..

 

Well Michael that’s partly correct; the bushing removal tool flared the bushing sleeve on the passenger’s side so I had to drop the subframe to get the job done in the end. I have a washer now that will prevent that from happening again.

 

Onasled, I like your signature !! lol

Both you & Randy are great MINI guys btw.