More front spring questions

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Topic author
Phils67
Posts: 578
Joined: Sat Mar 24, 2018 3:11 pm

More front spring questions

Post by Phils67 » Mon Jan 06, 2020 4:19 am

My j20 axle swap on my j2000 is coming along nice and near ready to go in.
1) are front lift springs designed for stock spring under axle setups? I am changing my original thinking on the build and currently have 4" rear springs and a setup that net me around 5.5-6" total rear lift and want to run 34x9.50-16 narrow TSL's. I plan to move the springs under the frame in stock configuration for now and run spring under axle, I can always add FSSR and SOA at a later time if I want. For now I want to keep it simple.
2) can someone tell me how far apart I need to weld the rearward spring mounts for the front springs? Like what is the straight line eye to eye distance on a stock, and from bottom of the rail to center of the eye on j10/j20's spring mounts also so I can keep a stock castor with these springs. I plan to weld the front mounts right at the front of the frame rails and would like stock shackle angles
3) which spring manufacturer do you recommend for the best results. Ride quality is more important to me than offroad ability because it won't really see much offroad. It's a 4.0 inline 6 so the spring rate would need to be comfortable with about 600lbs under the hood with all the add on accessories.
I'd like to get the springs/shackles/brackets addressed before I get the axle off of the bench and remove the old suspension and axle so it's not sitting on Jack stands while I wait weeks for suspension parts to show up. If the mounts are welded in place before I remove the old stuff it will make installation of everything go quicker and easier. I want the front to be like the suspension mounts were assembled at the factory and lift the front accordingly to match the rear. It doesnt need to sit level. I'm ok with it being a little bit ass-high because it levels out when there is weight in the bed.
1967 Gladiator J2000/ 4.0MPI/T18/Twin sticked D20/ locked 44/welded 53/4.27s/4" Hell Creek,35s, pending J20 axles and late model spring-under-frame front 3.73 with Detroit's, 4 corner disc brake, and 34x9.50 TSL's

1990 Comanche MJ/ 2.5TBI Renix/AX4/2wd SporTruck base model shortbed/daily driver

2001 Cherokee XJ/ 4.0/AW4/NP231/D30-35/backup Jeep

"I don't remember the Jeep you are talking about. Your Jeep addiction is so bad I can't keep track of all of them that come and go" -my wife


Topic author
Phils67
Posts: 578
Joined: Sat Mar 24, 2018 3:11 pm

Re: More front spring questions

Post by Phils67 » Tue Jan 14, 2020 4:28 pm

45.75" center of eye to center of eye, measuring in a straight line, is what I found elsewhere on the internet. Can anyone confirm this please? I don't think I am asking very much here. I found a wagoneer frame blueprint online and want to ensure it is accurate before I do this
1967 Gladiator J2000/ 4.0MPI/T18/Twin sticked D20/ locked 44/welded 53/4.27s/4" Hell Creek,35s, pending J20 axles and late model spring-under-frame front 3.73 with Detroit's, 4 corner disc brake, and 34x9.50 TSL's

1990 Comanche MJ/ 2.5TBI Renix/AX4/2wd SporTruck base model shortbed/daily driver

2001 Cherokee XJ/ 4.0/AW4/NP231/D30-35/backup Jeep

"I don't remember the Jeep you are talking about. Your Jeep addiction is so bad I can't keep track of all of them that come and go" -my wife

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Cecil14
Posts: 724
Joined: Mon Oct 01, 2012 6:40 am

Re: More front spring questions

Post by Cecil14 » Thu Jan 16, 2020 8:12 am

I'll be home this weekend and can get some measurements for you.

For your questions:
1. Yes, lift springs (at least for the '74+ years) are designed in an SUA fashion.
2. Will measure when I get home.
3. Can't really comment on manufacturers. Skyjacker used to be lauded as an amazing ride for a 4" lift, not sure if that's still the case? If you want stock springs, a local spring manufacturer should be able to set you up. If you're looking for something online, I have ordered from General Spring. They were great on the phone. They don't build all of their stuff, so if you are concerned about origin, phone them up and ask about specific products.
1983 J-10 - 4.6L(MPFI)/CS130D/Hydroboost/NV3550/D300/44/44/3.54/Disc-Disc/32s/42 gallon 'burb tank


Topic author
Phils67
Posts: 578
Joined: Sat Mar 24, 2018 3:11 pm

Re: More front spring questions

Post by Phils67 » Thu Jan 16, 2020 2:29 pm

Ok thanks. I know I have bashed them in the past but I was looking at the Hell Creek front springs for J10/J20 last night since that's the brand I have currently with the post style. I like the rear but have never liked the front. Also been thinking more and more about using a front drop box style spring mount and doing pass-thru-frame style rearward mounts like a GM truck of that generation. WFO Concepts makes a pretty stout setup for the front mounts that are a 31.5" spring center which is basically the measurements I gather going off the spring perches on my axle. If you can double check that distance I would appreciate it. Center to center of the springs. I am not 100% decided just yet how this is going to go. Too much time on the internet and not enough time in the garage the last few days. If I go with the HC springs I think a 4" with the other style mounting points will get me sitting close to level unloaded. I really just need to start drinking more beer so I will buy expensive stuff without second guessing it and build it all with whatever shows up in the mailbox lol.
1967 Gladiator J2000/ 4.0MPI/T18/Twin sticked D20/ locked 44/welded 53/4.27s/4" Hell Creek,35s, pending J20 axles and late model spring-under-frame front 3.73 with Detroit's, 4 corner disc brake, and 34x9.50 TSL's

1990 Comanche MJ/ 2.5TBI Renix/AX4/2wd SporTruck base model shortbed/daily driver

2001 Cherokee XJ/ 4.0/AW4/NP231/D30-35/backup Jeep

"I don't remember the Jeep you are talking about. Your Jeep addiction is so bad I can't keep track of all of them that come and go" -my wife

User avatar

Cecil14
Posts: 724
Joined: Mon Oct 01, 2012 6:40 am

Re: More front spring questions

Post by Cecil14 » Wed Jan 22, 2020 8:07 pm

I haven't forgotten you, just haven't had a chance to sneak out and take the measurements. Will try to get to it over the next day or two.
1983 J-10 - 4.6L(MPFI)/CS130D/Hydroboost/NV3550/D300/44/44/3.54/Disc-Disc/32s/42 gallon 'burb tank


Topic author
Phils67
Posts: 578
Joined: Sat Mar 24, 2018 3:11 pm

Re: More front spring questions

Post by Phils67 » Thu Jan 23, 2020 7:53 am

No worries. It's been like 10 degrees here so I haven't been working on it lately
1967 Gladiator J2000/ 4.0MPI/T18/Twin sticked D20/ locked 44/welded 53/4.27s/4" Hell Creek,35s, pending J20 axles and late model spring-under-frame front 3.73 with Detroit's, 4 corner disc brake, and 34x9.50 TSL's

1990 Comanche MJ/ 2.5TBI Renix/AX4/2wd SporTruck base model shortbed/daily driver

2001 Cherokee XJ/ 4.0/AW4/NP231/D30-35/backup Jeep

"I don't remember the Jeep you are talking about. Your Jeep addiction is so bad I can't keep track of all of them that come and go" -my wife

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