Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: cLAY on July 21, 2014, 10:12:47 AM

Title: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: cLAY on July 21, 2014, 10:12:47 AM
Mostly for discussion as I keep having this bounce thru my head.

My next build will be an expedition style rig, not sure if it will be a ZJ or XJ. I want a V8 for hauling a trailer but I also prefer a leaf spring rig for hauling a trailer. I've never liked the way a ZJ handles a trailer, stock or lifted. My old XJ handled a trailer just fine, even lifted.

Any thoughts? Comments? Not really interested in hearing how awesome YOUR ZJ handles a trailer, thats not the purpose of this thread.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: hps4evr on July 21, 2014, 12:15:14 PM
I've seen a couple pictures of zj's with rear leaf springs, so it's possible... But making them fit and mounted to the unibody could be interesting.
I like the ride and handling my Xj has but a v8 would be cool too.
What about a proper rear four link suspension with a sway bar?
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: Bnine on July 21, 2014, 01:08:49 PM
personally I'd rather air bag links or run adjustable shocks, or both than deal with the maintenance of leafs just for trailer hauling stability.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: cLAY on July 22, 2014, 08:01:18 AM
My big XJ I have long arms and the rear is 4 link, still seems pretty unstable when compared to my leaf sprung XJ. It has no sway bars but neither did my XJ. Both had about the same amount of lift. Both running the same axles.

The ride is definitely smoother, not so choppy.

What maintenance are there on leafs? Once I built my leaf packs I never touched them again.

I'd love to get my hands on a J8!
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: Vinman on July 22, 2014, 08:08:28 AM
My big XJ I have long arms and the rear is 4 link, still seems pretty unstable when compared to my leaf sprung XJ. It has no sway bars but neither did my XJ. Both had about the same amount of lift. Both running the same axles.

The ride is definitely smoother, not so choppy.

What maintenance are there on leafs? Once I built my leaf packs I never touched them again.

I'd love to get my hands on a J8!

I think a big difference in the two XJ's trailer handling is the lack of sway-bar on the coil spring equipped rig. I think its much more important to have a sway-bar on a coil sprung rig vs leaf sprung.

I agree with Bill, airbag assist with adjustable shocks will do wonders.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: cLAY on July 22, 2014, 08:32:38 AM
I've actually never tried towing with my lifted ZJ. Just my stock 5.9.  My lifted leaf sprung XJ towed better than the 5.9, handling wise anyway, power of course goes to the 5.9. ;)
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: cLAY on July 22, 2014, 08:39:09 AM
I've tried putting a a rear sway bar on the lifted ZJ but after the 3rd one snapped and went thru the tire I gave up. I would definitely put one on for towing though. An Exped. style ZJ would have a lot less lift and and probably not be so prone to snapping the sway bars.

Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: Bnine on July 22, 2014, 09:26:31 AM

What maintenance are there on leafs? Once I built my leaf packs I never touched them again.


Unless your suspension is crap and the leafs dont move, bushings only last a season if you wheel semi regularly and less if you wheel a lot.

If you have suspension that works, leafs sag pretty quick. Which is fine if you dont mind settling a few inches out, or running 2" of rear rake for the first six months.

If they arent going to see much work they should be fine, but if they are going to see work, they are a lot more to maintain than well designed link setup.

Not to mention, leafs that are soft enough to provide a decent balance with the front link suspension wont really be that much more stable than a decent link setup.

Thats why all the lifted rig rockets have bags installed to haul their 5th wheels. Pulling a 5th wheel with soft lift leafs sucks beans.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: hps4evr on July 22, 2014, 10:13:19 AM
Mostly for discussion as I keep having this bounce thru my head.

My next build will be an expedition style rig, not sure if it will be a ZJ or XJ. I want a V8 for hauling a trailer but I also prefer a leaf spring rig for hauling a trailer. I've never liked the way a ZJ handles a trailer, stock or lifted. My old XJ handled a trailer just fine, even lifted.

Any thoughts? Comments? Not really interested in hearing how awesome YOUR ZJ handles a trailer, thats not the purpose of this thread.

What size/weight of trailer are you planning to use? If it's not too heavy or large/long an Xj with proper gears and tire size could get everything you want... Minus a V8 ;)
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: JackstandJohnny on July 22, 2014, 12:00:19 PM
why not do a WJ with the wishbone suspension? build a beefy wishbone with JJs and do that?

my old WJ was way, way more stable than the stock ZJ ever was....

or is the current niner the jeep you plan to build?
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: w squared on July 22, 2014, 02:30:51 PM
Mostly for discussion as I keep having this bounce thru my head.

My next build will be an expedition style rig, not sure if it will be a ZJ or XJ. I want a V8 for hauling a trailer but I also prefer a leaf spring rig for hauling a trailer. I've never liked the way a ZJ handles a trailer, stock or lifted. My old XJ handled a trailer just fine, even lifted.

Any thoughts? Comments? Not really interested in hearing how awesome YOUR ZJ handles a trailer, thats not the purpose of this thread.

My thought is that you are a glutton for punishment....but I'm interested in how this will turn out.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: 4PLAYZJ on July 24, 2014, 10:47:45 AM
What about using timbren springs as a bump stop? They're like air bags but require no air in them. Setup the timbren bags so when the back is weighted by the trailer the the suspension pushes up onto the bags and controls ride height but when offroad the suspension is still free to articulate.

Just and idea.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: ARBXJ on July 31, 2014, 08:13:25 AM
My 2 cents probably isn't worth 2 cents but I would look at what the commercial guys use and to the extent possible and within financial reason model something after them. My first Jeep was and is a 1990 xj inline 6 and I wud never give it up and it has never run better thx to Dave and Eric. If airbags are the thing them use em, if u want to experiment then u may not be happy or it may work out fine, sometimes the flip of a coin. Jeep forum in the US usually has someone who has tried and succeeded and many more who have not so very likely someone has tried this before. I expect you will make the right decision. I grew up on a farm and whenever my father was thinking something thru in his mind, he went outside, looked at what he was considering, sat on a home made sawhorse and rolled a smoke, by the time he was done, he usually had an idea of what he wanted to do. Maybe you need to build a sawhorse first and roll a smoke, tough to beat an xj.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: ARBXJ on July 31, 2014, 08:47:40 AM
Visit www.expeditionportal.com
Title: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: morerpmfred on July 31, 2014, 09:11:36 AM
Clay is a family man. Last person to roll up a joint so calm down.
Like clay I to am looking at all the options out there for the fourth or fifth build.
So what I am looking at is what the stock xj / mj / zj towing capacity is for the unibody is.
2000 pds for xj. 5000 pds for a mj and do not know what it is for a zj.
Leave springs length on a xj is 51 inches. Mj is 57. Industry standard for leave conversions are the chevy springs at 63 inches. The all pro long travel springs are 58 inches I think.

Am currently looking for rust free comanche for expo style trail rig build.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: dubbleJs on July 31, 2014, 10:28:27 AM
Clay is a family man. Last person to roll up a joint so calm down.
.

Haha...to me arbxj seems quite calm and he also said roll a smoke...not a joint. And who says a family man can't roll a joint anyway?? To each his own.  ;)
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: ARBXJ on July 31, 2014, 10:58:36 AM
I am old school Bud, where a smoke is tobacco, if I wanted to say joint you would have read joint, the point of the story is people can usually think things thru in their own way and get to an answer.
Title: Re: For Discussion: Rear leafs on a ZJ(Expedition build)
Post by: morerpmfred on July 31, 2014, 12:39:31 PM
Sorry me have dyslexia thinking.