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Discussion Starter #1 (Edited)
My 2008 451 Passion is in its 12th year of all year driving on salted roads in the winter and humid summers. This winter the front end started making loud crunching sounds when turning sharply. I knew I would need to take apart the front end to figure out what was happening, but it also felt safe to drive for a few months until I had a vacation. I gave myself one week to tear apart the front end, figure out what needed to be replaced, order the needed parts and install them.

This is that story.

 

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Discussion Starter #2 (Edited)
I felt it was easiest, after years of removing smart body parts, to take off the whole front end (the front piece and two side fender panels) as a single unit. it was very easy. I also removed the 'hood' and the panel above the fresh air intake in order to access the top of each shock absorber. And the side rocker panels.

I found the that lower portion (the smallest diameter portion) each each spring was broken and was causing the crunching sound. The bottom of each spring was able to extend below the lower mount point on each shock.

 

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Discussion Starter #3
Additionally, the bellows that protect the shock absorber were split (4); the bearing (#7) was seized (it allows the shock and spring to turn easily); the 'spring insulators' were corroded or missing (6).



Parts 6 (two required an upper and a lower) & 7 were corroded or missing and needed to be replaced.

 

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Discussion Starter #4
So I ordered the following parts with a cost around $175

Bellows with KYB strut boots SB108 from Rock Auto $11.08 each side
Upper strut (spring) mounts with bearing REIN AVQ0481 from Rock Auto $11.21 each side
Lower spring insulators 451-322-01-84 from mbpartsexpress.com $6.72 each side
(this just sits on shock plate and spring is prevented from turning by a notch in the insulator)
Upper spring insulators 451-320-00-26 from mbpartsexpress.com $5.74 each side
(the old ones were totally rusted)
New Lesjofors front coil springs from ebay $94.89 /pair from qeautoparts1




These did fit but they took a while to figure out that they look different from the originals and have to be muscled into position.


The small object is the bearing and it sits inside the larger rubber spring mount. The rubber mount was fine but I could only find them as a pair.


The springs are from Sweden and both have what seems like a cut or notch near the top coil. Concerned that this could rust and break prematurely, I sprayed the notch (the size of a pencil tip) with rubberized undercoating. I also sprayed the insulators for good measure since they were the most corroded.
 

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Discussion Starter #5
Taking the old parts out:

I bought a nice air impact wrench for $39 from Harbor Freight and some impact sockets, including extension bars and swivel heads and spring compressor, since I knew the top nuts on the shocks were very hard to remove with any other tool (some others have welded bits onto the shock to keep the piston from turning). I found my shocks were still working fine and I did not want to replace them if I did not have to. Replacement shocks start around $50 each from Rock Auto. Tools needed cost about $130 if I don't include the impulse purchases like a mechanics cart, nice creeper, and other stuff that kept calling my name.

The top nut(s) came off easily with a 1/2" air impact wrench and then I removed the lower ball joint, stabilizer link and steering outer tie rod end.

Seeing that the front brake rotors looked bad, I decided to replace them with an upgrade kit from Rock Auto - POWER STOP K5695 Z23 Evolution Sport Brake Upgrade Kit with coated and slotted rotors and ceramic pads to reduce dust.

 

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Discussion Starter #6 (Edited)
I painted the rotors and calipers using a Dupli-Color BCP101 ($9 from Amazon) caliper paint that almost matched my car (again since 2008 - see my original post here: DIY - painting brake calipers and drums )

And shoved it all back in place:

First put lower insulator on shock; then fit small end of coil spring onto shock; then push wide end of bellows onto shock (the small stop is a complete pain to push over the threaded part of the shock absorber); use a spring compressor to compress the spring; then put the upper insulator, the bearing and rubber spring mount over the threaded portion of the shock and finally the nut that holds it all together. I won't tell you how hard it is to get the spring compressor disentangled if you don't grab the spring in the right place. Too close to the end and it gets stuck in the coils, too far away you can't compress the spring enough to get the nut back on. But it wouldn't be a fun vacation if I didn't have a puzzle to figure out.

Then, assuming the shock and spring assembly is together, just lift the upper end into the cavity above the wheel well and guide the lower ball joint into the steering knuckle. Fit the upper stop (a rubber coated mount) and the upper nut and the nut on the ball joint.

The install and tighten the nuts for the outer tie rod and stabilizer link. Reconnect the ABS cable.
Then I mounted the pretty new rotor, the caliper support and caliper.







Then put the front end back on along with side rockers (I also replaced on that was torn up badly.)
Finally the torque the tire and it should be done.

 

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I Have already got my front end off for radiator issues.......... hmmmmmm if money was no object..... Cant wait to hear the after driving review.
 

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Discussion Starter #10
The car rides like a champ again. Turning is smoother and bumps seems to be less pronounced. Brakes were always good, but will be looking out for how dirty the front wheels get now, the OEM pads seem to create a mess within a week.
 

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Hind sight on this repair. Are shocks still holding up or if able would you recommend replacing them too at time of repair. Is there a full new complete strut assembly available .?
 

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Discussion Starter #12
Hind sight on this repair. Are shocks still holding up or if able would you recommend replacing them too at time of repair. Is there a full new complete strut assembly available .?
Shocks were fine. The springs and shocks are separate and not sold as a set, these cars do not use strut packages.
 

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I am tempted to replacey front end suspension with kw or d2 coilovers kits. No stranger to car work, but the 451 looks simpler (as far as strut mounts) than the 453, I took the struts out once to throw SM lowering springs in. But want to be much lower. Will check out your thread on the caliper Paint.
 

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Picked up my struts/shocks from Autobahn, got the ED heavy duty version which gave me a touch more ground clearance. I would replace the shocks, as that is what holds the springs in place and at least here in the great white north, rust is a problem. (the white being road salt)
 
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