(CJ5) Springs Over Axels ???

SOA stinks.

 

I'd have to politely dissagree there.

Soa and Sua have there places. The problem with Soas are people that think all you have to do is put the springs on the top of the axle. Really what you have to do is redesign the whole suspension system. This requires too much effort for most people so they hack it. Things like rotating the pinion up and doing a cut and turn on the knuckles to achieve proper caster angles is more than most bargain for, not to mention the whole steering and spring wrap issue. Of course most people are just looking for a cheapo lift so they can slap some big tires on there jeep and cruise the mall. If your going to the effort of redesigning the whole thing you'd better want to use it.

Kevo

 

well stated, Ghetto Fab. i love a soa, though they are never properly done cheap. for the majority of people i think bolt on is best, but for the ones that understand steering and suspension set-ups and aren't afraid of having to redo stuff to suit, soa is butta. anyway, i know i chringe everytime i see a butch suspension job weither soa or sua, especially on the road.

 

That's fine, but I'd like to hear why a SOA would be better than a SUA with comparable lift and spring rates. So far we've only listed ground clearance under the springs and cheaper parts IF all the above mentioned skill, effort and knowledge is applied. Where's the big win?

 

But that's the whole point ... the ride has nothing to do with the position of the springs, rather it's because of the spring rates - soft springs are soft springs. Put soft springs under the axle and you get the same ride.

Another point that will tag me as the reactionary geezer that I am - why do you need so much lift? These jeeps will clear 33s and 34s typically without much modification. More lift just makes them tip over more easily.

Personally I think that coils make much more sense for the front, and outboarded SUA lor SOA leaves for the rear. That would be the best way to get a better ride and adequate stability out of this wheelbase and track width.

 

I don't disagree that there are benefits to both set ups. I have both and have done both. The main problem is like you guys have said. Most people that do the SOA do it because they think it is cheap. Therefore, they do not realize how much redesign and fab work goes into it to make it work safely. If spring clearance is an issue, just get some of the plates that have the skid plate built on to them to protect the ends of the u-bolts. If you do any serious offroading, you are going to drag your axles over rocks on a regular basis, its not that big of a deal if you plan ahead and use rock rings and things like that. I would comfortably lift an old CJ 4" and run 33's but that is about as far as I would go on stock axles. SOA usually gives you 5" - 5-1/2" of lift and you could fit 35's under it. When it gets up that high, yall can do what you want to but I am outboarding the springs and going to full size chevy axles. Not my choice if I am going to drive it on the highway much, but most of what I work on is for offroad only. As for the coils, I don't know what is would be technically right. However, most of the guys I ride with have gone to coil spring rear and leaf spring front. One guy that rides with us had this set up on a Samurai and it seemed like it would crawl anything. Right before New Years he went to coils on the front too and he had trouble with things that were no problem for him before. Not 100% sure coils all around was his problem, he may have just not been use to them. He should have just left it the way it was though. Just my .02.

 

The reason I thought coils would be good on the front is for stability. Pre '76 Jeeps in particular have a very narrow frame, and having the springs in that far from the wheels causes significant body roll ... unless the spring rate is high (stiff!). Moving the springs as far outboard on the axles as possible increases roll resistance and provides stability or allows lower spring rates, your choice. With coils, the spring can be moved outward without preventing the wheels from turning - and they also allow the front wheels to be further forward (or rearward) on the vehicle, maximizing approach/departure angles.

I've heard that coils unload much more easily than leaves - that they have little resistance to stretching. I'm sure the dynamics of both spring types are more complicated, which makes a direct comparison difficult. EBs used to regularly have a problem with "Bronco hop" on the stock front suspension, which I recall was cured with the right shock damping. Leaf springs probably have a lot of internal damping (friction and resistance to flexing) which would make them less responsive to small obstacles; they would ride rougher.

 

If you watch the rigs with the four link front and rear set up, there is quite a bit of body roll and the ones I have driven or ridden in just don't seem as stable. Leaf springs on one end does cause a somewhat rougher ride than the coils but stability is the main reason my group stays with them. The wheelhop is one of the reasons they use the leaf spring set up on the front. The rear can handle more wheelhop than the front can and is easier to repair if you break something. Most run TJ or Caprice coils in the rear and stock or mildly lifted Wrangler springs on the front. In some situations, they handle better than having coil over shocks all around. It just seems to be the best set up for someone on a budget. The pres. of our club runs an EB and has yet to find the right shock to calm down the wheelhop in his front end. It is constantly eating lock outs and ring and pinions. Before he went to chromoly axles, he was having to carry at least two spare short sides every time we went out. One day we will get him upgraded to a D60 front and maybe he can make that last. He seems to like the stock 44,9" rear width though but it is just not enought for the HP he is getting out of the 5.0 in it.

 

The more arch a spring has the stiffer it will inherently be. Think of the worst case scenario of show trucks and you'll see what I mean. As far as our discussion thats probably less of an issue, but a flatter spring will generally ride and flex better than an arched spring of similar rate. If your going to the trouble of bolting flexy wrangler springs on in an attempt to get a lot of flex then your going to have to change a lot of other things as well so you might as well gain some more clearance and put the springs on top. Once again this goes back to designing the suspension for its intended purpose whatever that may be.

Most people also run leafs up front simply because its easier. Its much easier to package up front. If you go coils you will need to fab some links and thats where things get complicated. You have to make sure the links will clear everything at full stuff and not smack the oil pan or starter. The hardest part is figuring out how to mount the panhard and get zero bumpster. Not imposible, but its way more difficult than the rear. Leafs are very easy and forgiving to work with.

Kevo