1999 Expedition XLT - Aftermarket Coil Springs, Spacers and Shocks

[J Hairston]

Hello All,

Long time lurker, first time poster.

I want to share my experience in working to "lift" my Expedition to accommodate larger wheels and tires.

Lots of research here and questionable/limited assistance online pretty much pushed me to use trial and error in determining the best way to go about a small lift of 2-3 inches to accommodate 18in wheels and 275 series tires on my 1998 XLT.

Summary of replacement parts:
1. MOOG constant rate coil springs
2. Daystar 1inch coil spring spacer
3. Rancho RS55112 extended length shocks

Front torsion bars were cranked slightly but clearance on my particular truck looks to be high enough to accommodate so not much done there.

I raised the rear end up and pulled out my old rancho shocks (5 years old) and then removed the rear swap bar on both sides to allow the rear suspension to hang low enough so that I could remove the factory coil springs. Rented a spring compressor from Advance Auto Parts and compressed the new springs enough to fit them back into the stock position, with the coil spring spacer mounted on top of the spring. Replaced new shock and repeated on other side of truck.

The issue that I've found is that the truck has considerably more "bounce" over larger bumps than it did before. I'm a bit surprised since I thought that the extended length shocks would be able to control rebounding motion of the new coil springs considering the shocks "should" be able to accommodate up to 4inches of lift per the manufacturer. Driving 2 hours on the highway was mostly pleasant on smooth to decent roads, but larger bumps and large expansion joints seems to result in more bounce than I think most would feel comfortable with.

My guess is that the shocks don't have enough dampening control to effectively manage the up and down motion of the new stiffer springs. Next move is to research stiffer shocks with better compression and rebound control to see how the truck handles. The big questions is what brand is best for that.. I will report back once I get around to that. Until then, I will likely limit my driving to shorter trips with routes that won't upset the suspension setup too much. Posting pictures below for reference

 

[J Hairston]

 

[J Hairston]

 

[J Hairston]

 

[J Hairston]

Update.. will be purchasing Rancho 9000 series adjustable rear shocks. Hoping that this will fix my bouncy rear end.

Also wanted to share an update on the reason for all of this work!

 

[02Sexpedition]

I’m getting ready to replace the entire front drive train and components as well as the rear springs/shocks and adding 1.5” spacers. New torsion keys as well for another inch or two up front. Did you actually need the spring compressor? I’ve seen a few videos where it seemed it wasn’t needed.

 

[J Hairston]

I’m getting ready to replace the entire front drive train and components as well as the rear springs/shocks and adding 1.5” spacers. New torsion keys as well for another inch or two up front. Did you actually need the spring compressor? I’ve seen a few videos where it seemed it wasn’t needed.

Definitely needed the spring compressor for the installation of the new springs. You could probably get away with dropping the axle down far enough and disconnecting the rear sway bar enough to beat the factory springs out with a hammer like I did.

Installing the new springs with the coil spring spacer necessitated the use of the spring compressor 100%.

 

[02Sexpedition]

Thanks. I planned on dropping the axle anyway so I should have plenty of room. Hopefully

 

[02Sexpedition]

I replaced the trailing arms so there was no need for a spring compressor with my lift. 2 1/4” spacer lift on the rear. Trailing arms out will give you Plenty of room to get any spacer in.