Last night I finished my suspension upgrade which was KYB AGX shocks, B&G springs, and Energy Suspension polyurethane FSB bushings and endlinks. There are lots of other posts (use search!) about how these aftermarket parts affect your ride and handling, so I'm not going to review that aspect, but rather share my personal experiences that I think could help others.

Ok, replacing suspension parts. My car is a '99 GLE with 64,000 mi, driven through Michigan winters (think mass corrosion)

Here are the parts that needed replacing:
Front:
strut spacer (54329-39U00) - was torn at the notch, looks like they're meant to do this
strut bearing (54325-5V000) - both of my bearings had leaked a bit of grease
polyurethane sleeve (54034-85E10) - brittle, and one even cracked when I removed it

Rear:
strut spacer (56218-61L10) - these were moldy and badly disfigured, which let water in to rust up the tops of my struts
rubber seat (55034-31U00) - compressed enough to need replacing
polyurethane sleeve (55031-33P10) - same story as the front sleeves
cover washer (55248-01U00) - corroded quite a bit
isolation bushing (56218-61L10) - compressed and disfigured

Here are the parts that I wasted money on replacing:
Front:
dust boot (54050-31U01) - my car is a '99 so it came with the newer boots, which are more durable, so these were in great shape
rubber seat (54034-0W000) - not too badly compressed, could have been re-used

Rear:
dust boot (55240-01A00) - doing as good as the fronts, and I'm wishing now that I would have just cut the bumpstops and saved the $50 for a set of KYB boots

To replace the polyurethane sleeves I used 3/8" helical-cut spiral wire wrap from Radio Shack. This is the stuff they carry in bags in the stores, no need to buy it online. I'd suggest two bags, since I used up my entire bag on the front springs and ended up re-using the poly sleeves for the rears. I'm also not sure if I have enough isolation, but I haven't had any noise yet.

Those orange pieces of paper that are supposed to serve as strut gaskets or spacers are worthless. The fronts aren't so bad, and in fact I ended up re-using mine, but the rears were all warped and crumpled. Water and dirt got in and rusted the tops of my struts, filling both mounts with sand and seizing one of the piston nuts. I'm also thinking that water getting in through the strut opening is what causes the metal piece behind the rear seats to get so corroded on some of our cars.

I wanted to make my own spacers using exhaust gasket material, ala njmaxseltd, but couldn't find a source for the material. That's too bad, because now I'm worried about my rear suspension letting in more road muck if/when the new gaskets give way. If you look on the exploded view of the rear suspension that's been posted here before, there's a strut cover. I wonder if that would keep the junk out, and why didn't my car come with these?

With my shock/spring installation I also replaced the FSB bushings and end-links with Energy Suspension polyurethane. This really helped tighten up my steering wheel, which had a lot of play in it. A very worthwhile mod and a good value.

I've read posts where people claim only the top end-links can be replaced, but this is not true. The bottom endlinks can be removed if the strut is detached from the steering knuckle. When the two are unattached, the control arm can drop far enough below the FSB so that the link-to-control arm falls out of that hole in the end of the sway bar. The stock end-links on the car were badly deformed and I think they were primarily the cause of my steering being so loose.

I've got some AutoZone spring spacers that I might be installing, not sure yet. Haven't had a chance yet to play with the AGX settings which I'll do before even considering those suckers.

That's all I can think of for now, maybe I'll have a pic later.

 

thanks for the info.

 

just did my kyb install. i should have defitnetly bought the above items because mine were worn out completely. sometime later i will replace them.

 

how is your ride now? i just installed KYBAGX and B&G springs this week...the drop is sweet, but the ride is a little bouncier than i expected...i have the fronts set at 2 and backs at 4...the guy didnt cut the bumpstop though in the back and i bought new OEM ones, should that have been a MUST thing to do? i didnt replace alot of the other things u replaced cuz the guy looked it over and said rest of it was good...he put new polyurethane sleeves on tho, and the new front and rear dustboots, but thats about it...the back also sits a tiny tiny bit lower than the front when in fact i want it the other way around, cuz if theres people in my backseat or stuff in my trunk it'll look funny..would trimming the bumpstop raise that out and make my ride smoother than it is? and also putting sum spacers in btwn the springs?

 

Thanks for confirming the increased steering feel from the ES bushings. If you check out an old thread of mine, I had a very unclear answers and never got anything as straight-forward as yours.

congrats on the install too

 

Did you grease the ES bushings? I heard that if you don't they will begin to make noise.

 

Yes, definately trim the rear bumpstops. Right now you have like zero suspension travel in the rear, the car is just sitting on rubber. Cutting the bumpstops will reduce your bounciness, but if that isn't enough, try the 1/2 setting.

Are you sure the rear is sitting lower than the front? The rear wheel wells cover the tire more, which gives the illusion that the rear is a tiny bit lower if the ride is in fact even. Spring spacers will bring the rear up a bit if you want the car to look even, but then they reduce suspension travel again.

Yep, greased the bushings and haven't had any noise yet.

 

B&G should not be bouncy. It will be HARSH, but not bouncy. If you feel your ride is bouncy, trim up the bump stops.