Suspension Setup for OEM Fit Front Coilovers

June 17, 2020

This article is intended to be a great resource for people wanting to lift their truck or SUV as high as possible while still retaining excellent ride quality. Fox and King build high quality threaded body coilovers that will let you choose your own lift height, and compensate for additional weight from aftermarket accessories. Both manufacturers provide a recommended range of lift heights, however their recommendations are not very precise, and can result in poor ride quality. Our more accurate recommendations will allow you to lift your vehicle as tall as possible, without sacrificing ride quality.

0-2” or 0-3” lift coilovers | What’s the difference?
These lift heights are very common to see on aftermarket shocks. Longer, 0-3” shock have a longer extended length, while sharing the same compressed length as the 0-2” lift shocks. This allows the coilover to be set at a taller ride height. The 0-3” coilovers are sometimes referred to as “Extended Length”. Because these coilovers allow the suspension to droop further, an aftermarket upper control arm is required to get proper alignment and prevent interference with the coilover.

Maximum lift height vs Recommended Lift Height
Lifting your vehicle too tall, can put more wear and tear on the vehicle and result in a less than desirable ride. If the coilovers are lifted too high, the shock may be close to full extension and will not have adequate droop to follow the road. We refer to this as being “Topped Out”. When shocks ride around topped out they frequently reach full extension which makes the ride very rough and can cause them to make banging and thumping noises. As a general recommendation we recommend setting 0-3” Coilovers at about 2.5” lift (see chart below for exact specs). This provides a good amount of lift, but more importantly will provide a good ratio of up/down travel. Too much preload/lift height will also cause excessive angles for axles (if 4WD) and steering components. If you want the vehicle to be lifted taller than 2.5-3”, you will need to look into other options, like: Spindle lift, long travel, drop down bracket kit etc..

Do the coilovers come pre-set to my lift height?
Coilovers come from Fox and King preset to their specs. Most of the time they will need to be adjusted according to your vehicle. Unfortunately this something we cannot adjust prior to shipping you the shocks. When you receive your coilovers, there is a LEFT and RIGHT side, the driver side may have a little more preload than the passenger side. This is normal. 

 

How to set the lift height on your coilovers:

  • Install coilovers as they were shipped
  • Settle suspension by driving back & forth, stopping hard. If ride height is ok, then proceed to torque everything down to spec. 
  • If you want to lift the vehicle taller, measure the coilovers at ride height (on level ground, Top of top hat to center of lower shock bolt)
  • Jack vehicle up until desired ride height/appearance is achieved (or add weight to lower height)
  • Compare new shock measurements to our max recommendation (see chart below)
  • Adjust preload by the difference between your initial measurements and desired height
  • Do not adjust preload with shocks installed on the vehicle. Reference this article for more

 

Adjusting Preload on Coilovers
Adjusting the preload on the coilover will raise or lower the vehicle’s ride height. Adjusting preload can be done at home with a few basic tools, however we recommend taking them to a shop with a proper spring compressor to be done safely. When making adjustments, be careful not to damage the threads on the shock body. Make sure the weight of the vehicle is off the coilovers, loosen preload nut set screw and carefully rotate slowly. Sometimes a spray lubricant will be needed or a shock specific wrench to rotate the preload nut collar.

Pro Tips: 

  • Loosen the set screw just enough to release tension (do not remove pinch bolt), if it is too loose it can skip a thread.
  • Make sure the upper and lower eyelets maintain the original orientation.
  • Adjusting preload to lift your vehicle does not compress the spring. It’s very common to think the vehicle will ride stiff due to the “spring being too compressed”.
  • Threads showing on a coilover is not equal to the amount of lift the vehicle has. Spring rates and lengths can be different requiring a different amount of preload for the same lift height. A lot of thread showing on a coilover is not necessarily a major issue.
  • DO NOT: Add a shock spacer to the top of your coilovers
    Adding a spacer to the top of your coilovers will make the extended length of the coilover much longer. This can cause major issues with over extending the suspension damaging steering components, axles, brake lines etc. See this article for more details on why this is not a good option. 

How to Measure your coilovers

With your vehicle at ride height on level ground, measure from the top of the “top cap” to the center of the lower shock bolt. This is the shock length at ride height with the vehicles weight on the shocks. With some quick math, we can figure out where the shock is sitting and how much up or down travel it has from that point.
(see chart for max height suggestions)

 

Below is our recommended Max Lift height, based on shock measurements from Fox and King.
*Shocks with adjusters that share the same lift height, will also share the same shock lengths.

Vehicle Description Part Number Compressed Length Extended Length
Recommended Max Shock Length at Ride Height
05-23 Tacoma Fox 2.0 IFP Coilover 0-2″ FOX-985-02-002 17.6 22.225 20.625
Fox 2.5 IFP Coilover 0-2″ FOX-880-02-361 17.58 22.19 20.5
Fox 2.5 IFP Coilover 0-3″ FOX-883-02-025 17.58 22.52 21
Fox 2.5 Coilover 0-2″ FOX-880-02-376 17.59 22.13 20.5
Fox 2.5 Coilover 0-3″ FOX-880-02-418 17.59 22.55 21
Fox 2.5 PES Coilover 0-3″ FOX-883-06-178 17.19 22.42 21
Fox 2.5 Coilover 4-6″ FOX-883-02-048 20.45 26.25 24.625
King 2.5 Coilovers 0-2″ KRS-25001-119 17.308 22.375 20.75
King 2.5 Coilovers 0-3″ KRS-25001-119-EXT 17.3 22.6 21
03+ 4Runner Fox 2.5 IFP Coilover 0-2″ FOX-880-02-361 17.58 22.19 20.5
Fox 2.5 IFP Coilover 0-3″ FOX-883-02-025 17.585 22.52 21
Fox 2.5 R/R Coilover 0-2″ FOX-883-02-111 17.09 21.88 20.25
Fox 2.5 R/R Coilover 0-3″ FOX-883-02-130 17.09 22.38 20.875
King 2.5 Coilovers KRS-25001-278 17.246 22.313 20.75
King 2.5 Coilovers -EXT
KRS-25001-278-EXT
 N/A N/A N/A
King 2.5 Coilovers (KDSS) KRS-25001-243 17.308 22.625 21
King 2.5 Coilovers – EXT (KDSS)
KRS-25001-243-EXT
 17.308 22.875 21.285
07+ Tundra Fox 2.0 IFP Coilover 0-2″ FOX-985-02-004 19.4 25.325 23.25
Fox 2.5 IFP Coilover 0-2″ FOX-883-02-021 19.36 25.37 23.375
Fox 2.5 R/R Coilover 0-2″ FOX-880-02-367 18.86 25.33 23.25
Fox 2.5 R/R Coilover 0-3″ FOX-880-02-947 18.86 25.53 23.5
King 2.5 R/R KRS-25001-143 18.147 25.33 23.293
King 2.5 R/R
KRS-25001-143-EXT
 18 25.7 23.66
14+ F150 Fox 0-2″ 2.0 IFP FOX-985-02-015 18.28 23.21 21.25
Fox 2.5 R/R 0-2″ FOX-883-06-132 17.95 23.49 21.625
King 2.5 R/R
KRS-25001-331
 17.980 23.325 21.525
21+ Bronco Fox 2.5 PES Front Coilover FOX-883-06-212 or -209 18.79 24.26 22.50
Fox 2.5 PES Rear Coilover FOX-883-06-213 or -210 19.24 27.21 23.00
King 2.5 Front Coilover KRS-25001-392A 18.50 24.60 22.50
King 2.5 Front Coilover – with AOR Upgrade KRS-25001-392A 18.50 24.30 22.50
King 2.5 Rear Coilover KRS-25001-393A 18.50 27.00 23.00
07-18 Chevy/ GMC 1500 Fox 2.5 IFP Coilover FOX-883-02-028 15.015 20.365 18.69
Fox 2.5 Coilover 0-2″ FOX-883-02-121 14.9 19.34 17.66
Fox 2.5 Coilover 0-3″ FOX-880-02-525 14.98 20.34 18.66
Fox 2.5 Coilover 4-6″ FOX-883-06-079 15.28 21.41 21.5