I replaced my OEM Bilsteins on my 2002 Envoy, 91,500 miles today with Heavy Duty Bilsteins. It was much easier than I thought, definately a lot easier than other vehicles I have done in the past. Heres a few tips:
* You WILL need a "gear puller". The type that looks like this:
I rented mine from Murrays. It was a whole "front end gear puller kit" that rented for $99.99 but I got all the $$$ back when I returned it.
* A heavy (lead) hammer will greatly help you. Actually its as important as the gear puller!
* Recommended by Chiltons is some kind of support device (stands, jack, whatever) to put under the ball joint assembly to support the hub/spindle while the strut is out. I didnt do this because the hub didnt move after I took the strut off, hence I didnt feel any support was needed.
Now for the fun stuff.
1.) Jack up vehicle, support each side safely with jack stands. Remove wheels.
2.) Open the hood and take off the 2 nuts that hold the strut assembly in the strut towers. There will be 3 nuts in a row on top of the strut - Do not take off the middle one!
3.) Go down below. Take off the 18mm nut that holds the strut yolk on. Attach gear puller and tighten. Smack strut assembly yolk with medium force. This should pop it off. It took me about 3-4 good smacks before it popped off the cone shaped bolt. Make sure that gear puller is cranked down good too.
4.) Remove strut assembly. I had Murrays compress my springs and put on my new HD Bilsteins for $20.
5.) Ok. Now you have to actually remove the yolk from the OLD strut assembly. Thats this part:
You will need to remove the nut bolt completely from the yolk. Then grab your BFPB (BFPB - Big F-ing Pry Bar,lol ) to pry apart the yolk. I had to really really really really beat the pry bar in with my lead hammer to get it to open up enough to release from the old strut. You will see what I mean!
6.) Install new yolks on new struts. DO NOT TIGHTEN STRUT-TO-YOLK NUT & BOLT YET!
7.) Install new strut assembly onto the vehicle. Put the top 2 bolts in the strut tower and position the yolk to slide onto the cone shaped bolt. You may have to smack it on with the lead hammer. Then tighten the 18mm yolk to control arm bolt.
THEN tighten the nut and bolt holding the yolk to the new strut. This is important so you can easily turn it to position the yolk onto the control arm.
8.) Tighten 2 nuts under the hood, on the strut tower.
9.) Check everything for tightness. Place tires back on vehicle.
10.) Test drive and BE COMPLETELY IMPRESSED that you will need a cigarette afterwards because you are so relieved your GMT360 drives "better than new"
I hope this helps somebody. I found it to be terrible simple compared to other vehicles. Heck, you shouldnt even need an alignment (im going to get one anyways). The HD Bilsteins were $59.95 from shockwarehouse.com with free s/h! The difference in ride is astonishing. I cant believe how much better the HD Bilsteins handle these Detroit roads (and if there are bad roads anywhere in this country - its here!)