Suspension and axle questions for future build

[rstickley]

Since I sold my Scrambler 1.5 yrs ago, I have been miserable. Not that I can afford to build one now, but I am in the business to trade work for parts and start collecting. So, I have been thinking on what I wanted. I know that it I will be running a 5.3lt LS with a 4l60E, tires no bigger than 35" used mostly on road but for moderate trails. My main questions come into play with the suspension and axles. On my last one, I had a 4" Superlift with 35" tires. I really thought the ride was harsh and others that road with me also complained of it. I have been looking at the coil spring set up like Ian from Xtreme 4x4 did. My questions are:
1) Has anyone on here used a coil spring set up? How does it act on the road at hwy speeds?
2) Is the cost worth the ride difference?
3) Is there a leaf spring set up that will have a ride equal to coil?

Then I looked into axles and got extremely confused. I had a light duty 9" in my last one but it only had 28 spline shafts.
I have done some axle work but never cutting down length and ordering custom shafts but I do have access to people that have done this. Questions:
1) What axles would be the best, strength wise, that are the same width as stock?
2) Will the suspension decision make a difference in axle choice.

Sorry for the long post but if I think that if I slowly start collecting parts and thoughts, I can find a way to make this happen. Thanks for this group!

 

[Kane]

I think you can still get a good ride from leafs and save some serious money to boot. I run 3" black diamond springs and Bilstein shocks and this is the best riding Jeep I have ever driven. Even my wife doesn't complain and she gets motion sickness very easily. There are quite a few good choices out there, OME, BDS to name a couple that will give you the ride you are looking for and their springs are actually tailored to our Jeeps and not just some off the shelf crap.

 

[rstickley]

Thanks for the reply Kane. I sure thought more people would chime in on this subject.

 

[tower210]

I have a shackle reversal / leaf spring setup running custom Alcans with Bilstein shocks. It is the best riding Leaf spring CJ around town that I have ever been in. That being said, I don't think it rides or flexes as well as some of the best LJs that I have ridden in.... Its nice and soft around town, it just seems to transfer more crash from big bumps than LJs.

That being said, my perception is that a nicely design retrofit 4 link will cost a bunch more than my setup. Hit up Scrangler, or Mike on here. His shop has done a bunch of those conversions this summer.

 

[bigwalton]

Unless it's for hardcore crawling or there was something like falling into free parts or some other deal of the century, there's no way I'd personally bother with coils on a CJ-8, maybe it'd be a different answer for a short-wheelbase Jeep, but I still doubt it. I was just having the conversation last week that I'd never even go with an SOA setup and that level of complication for most builds. Have you ridden in a Scrambler with something other than a Superlift? The brand of springs and shocks make a huge difference.

Good leaf springs SUA for a rig like you describe can ride great, just like tower210 said. It's not the same as my LJ on a JKS JSpec 3.5" short arm lift, but it's FAR from anything anyone could ever call harsh or uncomfortable. I've ridden in/driven lifted coil spring Jeeps that are definitely worse.

Mine's on 35s and waggy axles (HD20/44) and just this year it's driven round trip from MI to Moab, MI to SD and all over the state, putting in 20-gallon tank's worth of miles at a stretch. Prior to this year it was on an old-school Rubicon Express 4.5" lift and now it's on a 5" BDS lift. If it didn't ride nicely on road at speed, I wouldn't have been able to put in those kinds of miles. I can roll down the highway at 80-85 with one finger on the wheel (I need to post a video I took of doing just that...)

Raymond/spanksjr is the same deal, he drives his all over and wheels the piss out of his with leaf springs and even gets his girl to ride along from MS to MI and back.

I simply don't see a viable argument for coils and links over a GOOD leaf spring/shock setup unless you're regularly in that last 5-10% of performance/flex from a leaf spring setup. (I have the same type of opinion for short arm vs. long arm lifts in stock linked Jeeps too.)

One thought, if you're asking about going four link, why would the axles need to stay stock width? Those don't seem consistent. If you're going for the absolute ultimate flex with links/coils on 35s, wouldn't you also want to be at least a little wider for more stability? Similarly, if you need to outboard springs in front, that's a lot less complicated than a 4-link, right?

For 35s I think my setup is just about perfect for a CJ in terms of width and affordability. It requires outboarding in front and welding perches in the rear but I think it's worth it for the wider stance and more tire/body clearance (which can become a problem at stock width with 35s.)

You can get bolt on kits to take care of outboarding. The 20 (CJ or HD) ring and pinion are actually larger and stronger than a Dana 44 and the HD20 gets you stronger tubes and stock one-piece axles with just enough extra width for stability with 35s without looking too wide. I got my rear axle for $50 from someone parting an 81 GW and the front '78 D44 was got in a trade for a pair of lift shackles. Add a set of Xenon wide stock-looking flares and many people completely overlook that I'm wider than stock.

My

 

[rstickley]

Thanks for the extensive reply! The only reason I was thinking about it was for the ride. After reading your reply and hearing about the other leaf spring manufactures ride quality, I think it would be best to stick with leafs and look at a similar set like you have. Thanks to all that replied and helped with feedback and experience!

 

[mysunnshine]

Leafs grow in length when compressed and then the tire runs into the body.

Sent from my SM-G920V

 

[bigwalton]

As an argument for links over leaf springs?

This is what I was getting at with the idea of how the Jeep is used. If you're going to be flexed out that hard that often and you can't otherwise deal with possibly getting the tires into the body, then maybe it's time to think about links. Similarly, if you had a super nice body that you never wanted to have a chance of getting into and setting bump stops accordingly wasn't an option...

That's also part of why I think it helps to go a little bit wider with the axles for 35s. Doesn't matter on pure suspension compression, but that little bit more helps when you get twisted up.