Greetings,

I completed my install of a FT 3" HD kit last weekend but I'm having an issue with the rear springs. I have Rock Hard rear bumper assembly, which is heavy as hell, and is causing the rear to sag an inch and a half so I'm almost always on the bump stops. I've been thinking of a set of hockey pucks in the back but would really like to go with a spring instead. Here are my questions. Is there a heavier duty spring out there for the JK? Could I use a 4 inch FT HD rear spring set? Could I use a set of 3" front springs, or could I use a set of springs off a different vehicle? I remember someone using F 150 springs a while back.

Thanks!!

 

honestly, the cheapest easiest solution would be to install a set of coil spacers but, you certainly could install ft 4" coils and that should help out. unfortunately, going with springs made by other manufacturers may not help out as no two coils made by different manufacturers will measure up the same. in fact, most coils tend to lift higher than is advertised and in some cases, a lot higher.

 

I would respectfully have to disagree with spacers. Think of it this way....you're already almost on the bumstops. That means the springs are either over compressing, or RIGHT at it. If you install spacers, they will compress even farther, and certainly be over compressed then. I think your best bet is to get on the phone with Full Traction and tell um what you have goin on. The BEST fix will be more springs.

 

and i would have to respectfully disagree with you. i have installed many full traction 3" coil lifts on 2-door and 4-door jk's and have had a chance to examine the amount of droop they saw with the addition of heavy bumpers. and, based on my first hand experience, i can tell you that the amount of droop is only 1/2"-3/4" at the most and this is FAR from the bump stops coming into contact with the extension. also, the bump stop extensions provided with the kit are designed to prevent the over compression of your coils and so this would not be an issue either. the problem i have seen with getting new springs is that depending on what you get, you could end up with a rear end that is just as low, lower or way too high. with coil spacers, you can determine how much lift you need to compensate for the sag and get what you need.

EDIT: i reread the OP's post and would have to say that there is in fact might be something wrong with the coils as if in fact he is seen that much sag, there is something wrong with them. i have run their HD coils and never saw this much sag in them. in the case of offtopics 2-door jk, she ended up getting something close to 5" of lift out of her 3" HD coils.

 

That is the route that I am going as well, i have the 2.5 coil lift from Teraflex but after adding the Shrockworks rear full width with tire carrier the rear dropped, I ordered 4- 3" springs and will be swapping them out this weekend. I can't believe you are that close to the bump stops with just a bumper added, must be some soft springs.

 

Thanks for the replies!
It didn't even cross my mind that the rear coils could be defective. I'll give FT a shout and see what they have to say.

 

I've got a RE 3.5 SF lift. After installing the RockHard bumper and tire carrier and then loading for a 5 day offroad trip I was about 1/2" down in the rear. I called RE and got a set of the springs from their 4 1/2" LA kit for the rear. Now when unloaded (no camping gear, refridgerator, or additional gas or water cans but with all my tools and recovery gear in the Tuffy drawer) I sit 1/2" high in the rear and when fully loaded sit level. I think it was a good choice. So I'd call your lift maker and discuss your needs with them and try to come up with an approriate spring. An alternative could be an airbag. I think I saw a writeup on doing that somewhere.

For what it's worth the RH bumper is heavy but it can take a beating. I've come down some pretty large steps and smacked the dogs**t out of it with no evidence but removing some of the powder coating.

 

I've also got to question the rear springs...I have a heavy bumper, and I also have a heavy Toyo 35" inch tire, racks, and carry two full jerry cans (tire and full cans is another 160+ pounds), and my rear didn't come close to hitting the bump stops.

 

I had my Black Diamond rear springs replaced under warranty by Superlift, so defective springs are certainly a possibility.

 

Since the OP said this, "I'm almost always on the bump stops." That's what I was basing my answer on. That's the direction I was going....defective springs.