2WD to 4WD Front Main Eye Conversion Brackets for 52" Springs on 1973-1980 GM Trucks, Pair

Pros:

• More vertical wheel travel available. The best comparison is our ORD custom springs in the standard mount locations vs. our springs in 52” locations. In stock mounts, we get 9.5-10” of travel, and with the 52” mounts, we get 11 to 11.5” of vertical travel. Net is roughly 1.5” of vertical wheel travel.
• If you are creating your own custom spring pack by cutting apart multiple packs and combining them, you can end up with a good soft spring with reasonable durability and good travel for the cost of junkyard spring packs. There can be a lot of value here.

Cons:

• You can’t really just bolt in a stock rear spring and expect it to work optimally. You need a custom-built spring of some sort, either our ORD Custom springs or build your own.
• A stock rear spring with an overload can easily act too stiff when the weight of the front of the truck pushes the spring down on the overload at regular ride height. If you remove the overload and don’t build out the spring with more leaves, they end up too soft, very prone to spring wrap, and have a very short life. Figuring out what to build is generally a trial-and-error system, meaning that you should have some idea of what you’re doing upfront to make this work.
• Very soft leaves on these trucks will cause body roll problems since they’re mounted so narrow on the axle. An example is a longer travel coilover system that uses comparatively very soft springs but they’re mounted several inches outboard on each side for a much wider spring base which adds a lot of roll stability. Unfortunately, you can’t mount leaf springs out by the knuckles so the very narrow spring base means a soft leaf will give a LOT of body movement. Once again, proper spring tuning can make this less of a thing, and good shocks and sway bars will also help.
• Approach angle can be a problem on hard trails. We’ve seen people have VERY long frustrating days on the trail running the front of a 52” leaf spring into every obstacle we encountered. The front of a 52” spring will stick out 2.5” more than an equivalent spring in a stock mount. This is a problem in a small tire trail rig.
• Crossover steering is a requirement. Stock type push-pull steering doesn’t work with 52s.
• Steering again… Some bumpsteer is inherent in a leaf-sprung vehicle with crossover steering. The more wheel travel you use and especially at taller lift heights (over 3-4”), the worse the bumpsteer gets. It can reach some truly eye-opening levels. Be prepared.
• The costs can add up. If you’re looking for extended wheel travel to use at higher speed off-road, you need a good shock system, and by the time you buy hangers, shackles, and a good spring to get the longer wheel travel, you’ve spent a decent amount of the money it takes to buy our 4-link coilover system, which will give you WAY more overall performance. We do understand that installing a coilover system isn’t trivial, and that can make a difference.

                You’ll notice there are only a couple of pros and a lot of cons for this system.  To explain this a little, we’ll talk about where the idea for this spring system came from.  In the beginning….  Some guy figured out that you could shuffle some bracket locations on the front of a square and move the main eye mounting point forward.  It wasn’t hard to move the shackle mounting point back and the old stock springs he had laying around could fit up front and man were they soft and flexy, especially at a time when custom packs were a lot harder to come by and you were comparing them to some ridiculously stiff lift kit springs.  The priority was trail use so crossover steering was already part of the equation and replacing springs regularly or figuring out how to build a custom pack was still next to free so it was all fine.  This is really the root of it, the cheap cost of the spring and being willing to put in the labor to customize it or deal with the frequent problems.  So that was and is the primary advantage of the longer spring system.  The base spring is cheap or free.  It’s really a big pro, if you’re the guy with the skills and patience to make it work.  When you start buying new springs and possibly still have to customize them on top of needing bracketry to make it work, the budget advantage just isn’t the same.

                The single other advantage is the extended wheel travel you get from the longer spring length when you have an appropriately built spring pack.  Realistically, you will never see that advantage to the longer spring on the street, in a camping truck (overlanding) situation and maybe not in every rock crawling situation.  The longer springs won’t hurt in those situations but you shouldn’t go out of your way to make 52s happen.  They’re really good for a guy that wants to run rougher trails and push the speed a little bit and doesn’t have the resources for a link system, yet.

Leaf Spring Length and Ride Quality

                Let’s jump right in.  These two things are not directly related.  A longer leaf spring will not give you a softer ride.  Period.  If this was true, a 6 foot long spring from a dump truck could be bolted to your half ton and it would ride great.  It obviously will not.  It doesn’t matter that it’s 6 feet long, what matters is that it’s from a dump truck.  Same thing with swapping 56” leaves into lighter duty trucks.  The longer springs were largely built for heavier rated 3/4T and 1 ton trucks and bolting them into a K5 isn’t going to change that.  So what I’m saying here is there are other factors that are more important than the spring length.

                Let’s step back a second and define some ride quality zones.  The one that matters to most people is  generally on road driving.  This would include rough city streets, railroad crossings, minor washboard and potholes on dirt roads, and so on.  This type of driving will typically use 6” or so of moderately soft wheel travel.  A next step is rougher dirt road, minor washouts and moderate speeds, in general terrain that would not bottom a system with 8-10” of wheel travel.  This is where we would classify most of your unimproved back country roads that people use for camping, hunting, fishing, etc.  The last step is anything more, whoops, larger rocks and rubble on a “road”, terrain that most people would consider rock crawling, etc.  This is where more wheel travel, large shocks with bypass systems, hydraulic bumpstops and precise wheel control all become important factors.

                What leaf spring length does give you is possibility of more spring travel.  Not guaranteed more travel but it’s possible because the longer the piece of material is, the more it can flex before it bends.  Now, when we start looking at the types of driving where more wheel travel really matters we can get an idea of when long spring conversions make sense.  Our ORD Custom leaves give roughly 9” of vertical wheel travel on the pre ’72 trucks with 44” front springs and a little more than that on the 73+ trucks with factory 47” springs.  These systems provide really good (amazing really) ride quality in the first 2 ride scenarios and aren’t terrible even with more aggressive use.  You DO NOT have to use an extended length spring to get a soft spring rate and good ride quality in most situations.  We can absolutely build the stock length springs soft enough for good ride.  If you’re looking to push the limits more, we have extended length systems to put a 52” spring in the front and with our custom springs you will get more wheel travel but keep in mind the situation where that is actually a benefit, it’s going to be in more extreme use.

Author: Stephen Watson - President and Owner, Offroad Design Inc