Over Strut Or Under Strut?

rhavermann · August 5, 2009

I am looking at different leveling kits and originally had it narrowed down to the RC and the Bilstein 5100 adjustable struts. I spoke with the guy who has done a lot of work on my wrangler and and a few things on my truck and he said to look at overstrut spacers. He said the adjustable struts and RC (understrut) will load the springs causing a rougher ride, where the over strut moves the whole assembly down, therefore no loaded springs. With my basic knowledge what he said seems to make sense.

More than personal opinions, I am looking for mechanical advice whether this is the case and how much of an impact it makes.

He runs a truck performance shop and has done this thousands of times so he definitely knows his stuff, but I had never read this on here before. He mentioned the ReadyLift, but after looking at it they only sell 2.25" for 2008 Sierra CC 4wd. I am looking for 2" max.

I appreciate any advice.

brims · August 5, 2009

The RC kit won't load the springs. It's simply a spacer. It does the same thing that an over the strut spacer does.

03blackz71 · August 5, 2009

The RC kit won't load the springs. It's simply a spacer. It does the same thing that an over the strut spacer does.

+1

Spurshot · August 5, 2009

All three methods effectively do the same thing. The spring is no further preloaded in any of them. The only thing preloading the spring in any of the three configurations is the weight of the truck. Any difference in ride quality of the three methods would be from other things like shock damping differences or such.

If both ends of the shock/spring assembly happened to have the same attachment style, it wouldn't matter if you put the spacer on the bottom or top. Just because they're different at top vs bottom doesn't change the effect of a spacer. The shocks with an adjustable height spring perch also doesn't change any thing affecting ride.

MS3DALE · August 5, 2009

The RC kit won't load the springs. It's simply a spacer. It does the same thing that an over the strut spacer does.

+1

+2

Matt_ · August 5, 2009

Here's a great way to think about it for those who aren't very "mechanically inclined":

If you do not take apart the spring assembly to install the spacer, you are NOT pre-loading the spring more than stock. Thus, a spacer on the top of the assembly does the same exact thing as a spacer on the bottom of the assembly, it increases the overall length of the assembly WITHOUT changing spring preload.

NOW, if you DO take apart the spring assembly and insert a spacer within the body of the assembly, this does increase the preload on the spring.... and is not recommended.

Edit:... eh, ok I guess you might still have to be mechanically inclined to understand.... so just trust us on this

blackout07 · August 5, 2009

I personally like to be on the bottom, but on top is cool too....oh wait...nevermind.

Matt_ · August 5, 2009

I personally like to be on the bottom, but on top is cool too....oh wait...nevermind.

MS3DALE · August 6, 2009

I personally like to be on the bottom, but on top is cool too....oh wait...nevermind.

brims · August 6, 2009

The RC kit won't load the springs. It's simply a spacer. It does the same thing that an over the strut spacer does.

+1

+2

Wooohooo, I answered 1 right.

FiretruckGMC · August 6, 2009

I personally like to be on the bottom, but on top is cool too....oh wait...nevermind.

GIGGITY!

rhavermann · August 6, 2009

Excellent, thanks guys that is exactly what I am looking to hear. I think I'm going to go with the Bilsteins. I have heard great things about the ride quality improvement and they aren't much more than the RC. I appreciate the replies!