2008 es350 rear strut replacement
 

Many threads about replace the rear and front strut, i didn't find anyone mention KYB SR4402 and KYB SR4403 Complete unit. Many seems to recommend reusing the spring and i was leaning toward that route until i see the whole KYB unit is just a tab more than the KYB strut itself i thought just buy the whole unit to make it easier on installation and not dealing with spring compression to remove and reinstall.
anyone have any experience with this whole unit , is the strut in this whole unit same as the KYB replacement for lexus es350
thanks

The answer is probably yes although I do not know for sure. I have, in the past, replaced the strut only. It will cost you another 20-30 minutes per strut to do and you also have to have an impact gun. The nut that holds the strut in place is a lock nut. The entire strut shaft will spin if you try to remove the nut with a socket or wrench. An impact spins the nut right off. You also need the impact to spin it back on.

I've found that it's not worth the time or effort or ride quality to do the strut only. When you buy the complete strut/spring/mount assembly you're getting new spring and rubber mount. That' makes a big difference in ride quality.

Yes I do,
I replaced my es350 rear struts with KYB SR4402 and KYB SR4403 and for the front I just replaced the struts and the car rides like a brand new car now. I did it 5 month ago. the ride was firm and the car was sitting a little higher in the beginning but now the ride is really nice smooth.

Finally got around to put those in on the back. Yes they are a bit firmer than original, especially on bad surface road. On freeway, mostly feel good. Consider the price difference between these KYB and OEM i think this is good value for my 12 years ofd car.

I replaced the fronts with all new OEM parts and only reused the springs, wound up buying parts from 3 different sources to get the best prices and think it still ran me about $500 for everything for left and right. Didn't realize the rears were bad until after replacing the front.
I am planning to do the rears in April once the weather is warmer and these strut assemblies are about half the cost of what I spent to replace the front.
Seems like a good choice to me, thanks for the recommendation.

it gets as smooth as OEM struts after 5000 km. that's my experience with KYB struts on my ES350.