1980 CJ7 CJ-YJ spring swap

[Cody]

I wanted to collect the knowledge of the hive mind here as I'm going to try and collect the parts to do a YJ conversion. The goal is to improve the ride/streetability a bit, and improve off-road/wheel travel a bit. This isn't meant to be a rig for pritchett, but I'd like to be able to do some moderate trails in it, and have it not drive like a tank around town (as much).

It's currently on Scout dana 44s, has a 1" body lift, and seems like about 4" CJ leafs (spring under) . I'm trying to find some stock fender to wheel center measurements so I can have a better idea exactly how much lift I have. I'd also like to lower it just a touch, but I don't want to hack too much into the fenders to fit the 35's. I guess the arc of the tire

I was planning on doing OME YJ springs, but they only come in a 2" lift height. Lowering 2" seems good, but again I don't want to hack into the fenders too much to clear the 35's. I may have to go to a taller shackle with them? or maybe a 4" Rubicon Express spring?

I know these lengthen the wheelbase about 1-2" total, and I'm here for that. That should improve road manners and off road/climbing ability. Do I need to move the front spring hangers, or does that stretch just get absorbed into the shackle angle?

I also want to run a longer shock up front (and probably rear), so I've seen people building new towers or buying f150 towers and welding them on. Any thoughts there?

I'm sure some of you have done these swaps over the years, so I'd love to hear some dos and don't and try to go with what should work the first time.

 

[Hickey]

This is the biggest part of the problem. The casting for the center section is also your spring pad/perch. The grooves for the U-bolts are cast at the same time as the rest of the center section, so adding a wider leaf spring opens up a can of worms.

 

[RockChucker]

I don’t know if they still exist, but my pops ran a 4” tuffcountry ezride lift on his YJ. It rode really good and controlled axle wrap well. Initially it rode pretty tall, but settled out and was probably in the 3.5-4” range. Are you planning on ditching the body lift or is that needed for drivetrain clearance?

 

[Tebbsjeep]

I think if you want some stretch to the wheelbase, I'd use the 7 leaf grand wagoneer front leaf springs. In the correct orientation they net you about a 4in stretch if you do both ends, and about 2 inches of lift. I ran them soa on my yj and they ride pretty good.

 

[Hickey]

I think if you want some stretch to the wheelbase, I'd use the 7 leaf grand wagoneer front leaf springs. In the correct orientation they net you about a 4in stretch if you do both ends, and about 2 inches of lift. I ran them soa on my yj and they ride pretty good.

That’s gonna be the same problem, because this axle is setup for 1.75” front springs and the perch with U-bolt grooves are cast into the housing.

 

[Agility Customs]

Do the rubicon express spring over springs in the front, Thank me later. they work perfect with 4" spring under springs in the rear.

 

[Cody]

Do the rubicon express spring over springs in the front, Thank me later. they work perfect with 4" spring under springs in the rear.

Hmm, tell me more about this? SOA front and SUA rear?

The waggoneer springs were an option, and honestly MY preferred option would be to stretch it like that into the 96-98" range, but that requires moving the gas tank (or investing in the motobuilt one) and stretch corners and body work etc and if I was going to put that kind of effort and time into a trail rig, I'd start with something cheaper and less clean so that I don't feel bad destroying it on the trail. This thing is worth less the more I mess with it, so I'm just trying to improve what I can without cutting it up or opening any major cans of worms.

I Just want this thing to be able to cruise around town to get ice cream for the kids, and do trails like Forest Lake and Poison Spider.

 

[Pile of parts]

I have a couple, or more, of the Rubicon Express springs. I'll make you a good deal if you decide to go that route.

 

[Cody]

Reading a little, some people say you get an extra inch from the yj stated height... So a 2.5" ome spring is more like 3.5" on the cj. Anyone experience that?

 

[iceaxe]

Reading a little, some people say you get an extra inch from the yj stated height... So a 2.5" ome spring is more like 3.5" on the cj. Anyone experience that?

Cody, sorry I've not been lurking the tech section. I've talked to many CJ owners about swapping to YJ springs using Rocky Road Outfitters kits, they've offered an Old Man Emu CJ to YJ suspension (as well as the stand alone conversion kit) for a decade and a half or more listing it as 3" to 3.5" lift using OME "2.5" springs based on customer feedback. Most reporting to run or planning to run 33's with it. So with the body lift you may or may not need little taller spring still for 35", (on paper anyway a 3" or 3.5" lift YJ spring might be closer to your current setup). Another thing to consider is most people are opting for the heavy duty kit, using the rear OME HD spring at both ends.

 

[Cody]

Thanks for the post. We ended up going with 4" RE springs, and it dropped the front about an inch, and the rear closer to 2 inches..which is great. I think I'll end up putting a winch on this thing and see where that sits the front, but we may end up adding an inch of shackle to the back to account for the weight of the hard top when it goes back on.