How high you must lift your off-road vehicles suspension, largely comes down to personal choice, but there are various factors to consider, before just lifting it the highest you can afford or find.
Lifted suspension is done for four main reasons:
- It allows the fitment of larger tires
- It allows more off-road clearance both of the body, and also under the axles if larger tires are fitted
- It allows for more suspension travel
- It looks good (let’s face it, most of us loved the lifted big wheel Hot Wheels when we were kids)
Since the early 80s, it has be popular to go for big lifts of 6 to 10 inch plus, achieved with either springs and appropriately longer shocks, or body-lifts, or both. (Unless we are talking Mud trucks, show trucks or monster trucks, where lift is measure in feet and usually involves a whole new engineered suspension setup.) This allowed for fitment of bigger tires, increased suspension flex, articulation and clearance. The handling however suffered as the higher center of gravity could cause rollovers on high-speed corners on off-camber sections of off-road terrain. While big lifts can be good, you should rather first decide the purpose of your rig, and what size tires you want to or need to run for that purpose, then going for as small amount of lift as you can get away with and still be able to fit them.
Overlanders like coil sprung Toyota Land Cruisers and Jeep Wranglers only really need around a 3 inches of lift to fit 35 inch tires, and can comfortably fit 33s on 2 inch lifts. Jeep wranglers even allow 33s without any lift if the fender flares are removed.
Benefits of this are that your handling remains largely unchanged, and suspension geometry are still correct or easily managed, and the fact that your center of gravity remains low so the risk of rollover is lower.
The bigger tires, already provide for some added off-road clearance, however, you should also fit rock-sliders on your rig in any case to protect and prevent body and sill damage.
Flex and articulation on the other hand can be improved with better rate springs, and higher quality bushes, as well as some control arm upgrades.
Generally, if your rig is built either for general trail riding, overlanding, rock crawling or some desert racing, lower suspension lifts, with high quality suspension components and gear fitted will outperform the higher lift rigs. Looking at competition and professional vehicle trends over the past few years, you will also notice that lower and wider with larger tires are the order of the day.