Author Topic: Yj to tj suspension fab question?  (Read 5728 times)

Offline Black-market

  • Trail Passenger
  • *
  • Posts: 28
Yj to tj suspension fab question?
« on: October 11, 2012, 01:42:45 PM »
Ok so I was thinking of trying to put a
Tj 4" lift kit in my Yj. A friend has the parts
Laying in his shop and said he'd give them to me cheap
So I figured I'd do some research. So has any one
Tryed or herd of this dosnt seem that hard to
Do. Couple questions I have are like
Tj and Yj frame and axles the same width or
No? And what problumes would you guys think
I would run into?

Offline calvynandhobbs

  • Honorary Member
  • Trail Master
  • ***
  • Posts: 3087
Re: Yj to tj suspension fab question?
« Reply #1 on: October 11, 2012, 03:34:12 PM »
If you do a google search on "leaf to coil conversion" you'll find a few write-ups and there are kits that are also available. I just did a quick search and saw RockKrawler has a conversion kit for $4500. The same thread on Jeepforum also said that there are kits starting at around $1800. Here's a link to the Procomp kit. This one is completely bolt on.

http://www.jeep4x4center.com/jeep-lift-kits/pro-comp/wrangler-yj-5-inch.htm

« Last Edit: October 11, 2012, 03:39:39 PM by calvynandhobbs »
1994 YJ on 37s

Offline Black-market

  • Trail Passenger
  • *
  • Posts: 28
Re: Yj to tj suspension fab question?
« Reply #2 on: October 12, 2012, 01:49:55 AM »
Yea I know they make a kit but I'm wounding
If tj stuff would also work from what I'm told
The frames and stuff are the same with and axle
Are the same I can get my buddy's stuff for 600
Bucks that's cheap compared to the kits iv seen that
Range 45-6 grand

Offline kirksjeep

  • Honorary Member
  • Trail Master
  • ***
  • Posts: 1267
  • It's hip to be square (headlights) !
Re: Yj to tj suspension fab question?
« Reply #3 on: October 12, 2012, 02:16:20 AM »
I think it would be easier to find a TJ frame and convert the YJ body to the TJ frame.  There is a reason that the conversion kits are so expensive.  To answer your question, yes the frames are the same length and the axles are too. 

Now this next part is just my opinion and I am bias since I have owned a YJ for the past 18 years, but a well set up YJ will perform as good or better then a TJ with the same amount of lift.  The coil springs can be pretty "bouncy " and that is not a good thing on trails in the North East with a lot of off camber spots.  I run the Rubicon Express XD 4.5" kit and it flexes pretty good.  My ability to flex has never been the reason I couldn't make it over an obstacle.  I think the R.E. XD kit is now about $1200 but it is bolt on.  Even getting your buddy's TJ kit you will still need all the frame mounts, control are mounts, and axle mounts which I don't even know where you would by those except the Jeep dealer or cutting them off a TJ frame at a junk yard. 
1992 YJ Sahara, 4.5 Rubicon Express ED Lift, 35" BFG MT, Custom Bumpers, SYE/CV Drive Shaft, OBA, Ford 8.8 rear, 4.10 gears, tie rod flip, 1"MML/BL
2002 KJ Liberty, 2" Lift, 31" tires/DD
2002 F-150 Harley Davidson 5.4L SC
2013 Explorer Sport
2006 Harley Road King Classic
1988 Honda Hawk GT

Offline Black-market

  • Trail Passenger
  • *
  • Posts: 28
Re: Yj to tj suspension fab question?
« Reply #4 on: October 12, 2012, 03:08:44 AM »
I have the rubicon 4.5 in my heep now
Just seems like the tjs flex a lot more then
Mine I thought about geting revolver shackles
But was told there not good on a daly
The mounts are not a issue as I can machine
My own at work

Offline Black-market

  • Trail Passenger
  • *
  • Posts: 28
Re: Yj to tj suspension fab question?
« Reply #5 on: October 12, 2012, 03:11:49 AM »
Was also looking for better ride on the road
That another resin. Have been thinking just stretching
With the rubicon 4.5 but idk

Offline gearhead1985B

  • Honorary Member
  • Trail Master
  • ***
  • Posts: 882
  • the Snozberries taste like Snozberries
Re: Yj to tj suspension fab question?
« Reply #6 on: October 12, 2012, 08:39:08 AM »
I have the rubicon 4.5 in my heep now
Just seems like the tjs flex a lot more then
Mine I thought about geting revolver shackles
But was told there not good on a daly
The mounts are not a issue as I can machine
My own at work


forget the revolver shackles extra flex is not a good thing and if you ever get in a situation to cause the suspension to unload they will throw the body further in the direction you don't want it to go

i have had my suspension unload a few times the front is not as bad as when the rear unloads the first time the rear unloaded on my i nearly pooped my pants and my brother ridding shotgun screamed like a little girl the hill i was on was like 75-80 degrees down and 2 other jeeps have endowed going down this hill and i was almost the 3rd but i did not hit the brakes like the other 2 guys did i mashed the gas and went for a ride the funny thing is this trail is meant for stock jeeps

my suspension set up is extremely flexy for a leaf sprung rig i can max out a 15" travel shock i have 5" uptravel and 10" of down travel in the front with less traveled in the rear due to mounting location and a shorter shock when i outboard the rear shocks i will have more up travel and the same amount of down here is my rig flexed out till the tire hit the bumper i have a 2" more down travel on the driver side shock and the passenger side was hard into the bump stop

my current suspension set up is d44's front and rear soa with waggy front springs in the front  and and toy rear springs in the rear netting me a 6" wheel base stretch rolling on 38" tsl's
this winter i am installing a full width d60 front and ford 9" rear  same springs just i am lowering the jeep 3" and installing slider boxes for shackles in the font for a more linear spring rate standard shackles in the rear both will be frenched into the frame to get the ride height i want  

in order to get better off-road ability out of any rig you need to improve 3 things ground clearance, traction and stability  

ground clearance- the only way to improve ground clearance is larger tires and ground clearance is measured under the lowest point of the vehicle to the ground that means the diffs to the ground not belly height so a lift kit will net you no ground clearance gain but only allow you to keep the body intact to run larger tires

traction- the only way to gain traction is to have a good quality off road tire and add lockers my preference on tires is bias ply tires on bead locks running low pressure and for lockers i prefer a spool in the front and a selectable in the rear and people will say you can't steer with a spool in the front all you need to do is phase your u joints in the front axle and add ram assist on my d60 i am running a selectable up front cause this jeep will see some street time and i am running drive slugs so i will not break another lock out hub and a rear spool hurts your turning radius more than one in the front cause it pushes in a straight line

stability- you add stability by going lower, wider and longer that is it imagine your jeep as a pyramid with the center of gravity being the point of it and the contact patch of the tire being the 4 bottom corners the taller the pyramid is the easier it is to tip if the point of the pyramid breaks the plane of the edges it will fall over so if you keep the pyramid short, fat and long the more angle from the horizontal before it will fall over


now i have not ever seen your jeep and don't know much about it other than what is posted but to improve flex on a standard leaf sprung yj or cj you can do several things a pull the sway bar or add disconnects i have not had a sway-bar on my jeep in 5 years and remove the track bars they hider flex a lot i know kirk has disconnects for the sway bars and front track bar on his jeep

with your leaf springs  you can do quite a few things like open up the clamps add soft rubber bushings not poly bushings and only torque your leaf spring shackle bolts to about 40ft-lbs those things will really smooth out the ride (for a while i was running my leaf spring shackles with the bolts loose enough i could slide them back and forth .25" and i had jamb nuts but the ride was really soft and smooth but i broke the bolts off road so i tightened them back up)

and to answer your original post it is not worth the time or me money to put a factory tj short arm lift on a yj if you had a long arm kit and a set of tj rubi d44's lying around that would be a different story cause with all the welding and cutting involved you would still only have a jeep with a marginal suspension geometry and a set spring rate if i was to do it i would make my own with a custom 3 link front and double triangulated rear suspension using ori struts
« Last Edit: October 12, 2012, 08:48:06 AM by gearhead1985B »
"If you can read this, Thank a Teacher, if you can read it in English, thank a SOLDIER"

https://www.masterpull.com/Index.aspx
http://www.taboocustoms.com/

Offline Black-market

  • Trail Passenger
  • *
  • Posts: 28
Re: Yj to tj suspension fab question?
« Reply #7 on: October 12, 2012, 08:48:03 PM »
Well thanks man pretty much sums that up haha
Are you located in ct be sweet to check out
You're rig and get some more ideas sense
You know some shit lol

Offline Mr Rock

  • Administrator
  • Trail Master
  • *****
  • Posts: 1571
Re: Yj to tj suspension fab question?
« Reply #8 on: October 12, 2012, 11:53:40 PM »
Anyone driving a YJ as a daily driver needs to get their head examined! trust me I have one, if you have short commutes then maybe it's not so bad. I can drive about an hour with no problem to get to a trail but by the 90 minute mark I am done! and that's doing it once in a while not everyday!!

I don't think it is worth it to try to make a YJ "streetable".
'89, 4.2, NUTTERED, Team Rush, 4" Lift, 1" BL, 1" MML & HD shackles , Flat Belly Skid, SYE, 36 x 13.50s
XRC8, 150w KC's, Herculined, Tauras Elec Fan, Dual Batteries, Aussie in front, 8.8, TJ flares & Spool in rear, topless all of the time!

Offline Black-market

  • Trail Passenger
  • *
  • Posts: 28
Re: Yj to tj suspension fab question?
« Reply #9 on: October 13, 2012, 01:55:00 AM »
Hahaha! One the things I love about the Yj
Is when u don't have sway bars or track bras
You bounce all over the road keeps it intresting
Hahah. But I think I'll just hold off and do the
Genright 14" comp long arm kit to it to get to the
100 wheel base mark. When I was a kid
I seen a Yj with the front wheel on the roof
Of a vw Beatle. So when I got mine my goal
Is to put a wheel on a stupid Prius roof hahah

Offline gearhead1985B

  • Honorary Member
  • Trail Master
  • ***
  • Posts: 882
  • the Snozberries taste like Snozberries
Re: Yj to tj suspension fab question?
« Reply #10 on: October 13, 2012, 07:00:07 AM »
Well thanks man pretty much sums that up haha
Are you located in ct be sweet to check out
You're rig and get some more ideas sense
You know some shit lol

no i am in illinios one of these years i will make it up that way to wheel again and me knowing alot well it took 6 yrs to get my jeep to what it is today and only like 3 months of acctual build time and a year or so of broken jeep time

Anyone driving a YJ as a daily driver needs to get their head examined! trust me I have one, if you have short commutes then maybe it's not so bad. I can drive about an hour with no problem to get to a trail but by the 90 minute mark I am done! and that's doing it once in a while not everyday!!

I don't think it is worth it to try to make a YJ "streetable".

lay off the drugs rock my jeep as the only thing i drove while i was in the navy just you need to be prepared to fix it over night when needed and i still drive it to work alot and will run it 80 miles on the highway to our farm (but it is double the cost compaired to pulling it on the trailer i love 4mpg on the highway but i get 8 in the city)  and i drove it half way across the country like 4 times my yj was the best dd i ever had and it is the only one i have kept for more than 3 years (but i am still young and dumb)

Hahaha! One the things I love about the Yj
Is when u don't have sway bars or track bras
You bounce all over the road keeps it intresting
Hahah. But I think I'll just hold off and do the
Genright 14" comp long arm kit to it to get to the
100 wheel base mark. When I was a kid
I seen a Yj with the front wheel on the roof
Of a vw Beatle. So when I got mine my goal
Is to put a wheel on a stupid Prius roof hahah

save your money on the genright kit and build your on slowly aquiring parts as deals come up always have a spare wade of cash (or a big pile of scrap metal)lying around for when a deal comes up. there really is no good  bolt in or weld in link kit that i have seen on the market the best i have seen is ruff stuffs kit all it is just joints and basic brackets but i think there are some better joints out there for the money i am awaiting some more real world testing on the metal cloak joints ( http://www.metalcloak.com/2-5-8-ODx2-5-16-W-Duroflex-Joint-w-Straight-Spud-p/7305.htm ) cause i belive they are better than a standard ruff stuff hiem ( http://www.ruffstuffspecialties.com/catalog/125RE.html ) and the cost differance is negligable
« Last Edit: October 13, 2012, 07:28:02 AM by gearhead1985B »
"If you can read this, Thank a Teacher, if you can read it in English, thank a SOLDIER"

https://www.masterpull.com/Index.aspx
http://www.taboocustoms.com/

Offline kirksjeep

  • Honorary Member
  • Trail Master
  • ***
  • Posts: 1267
  • It's hip to be square (headlights) !
Re: Yj to tj suspension fab question?
« Reply #11 on: October 13, 2012, 07:15:55 PM »
My YJ stopped being my daily driver when I was 24.  I don't think my kidneys would still work of I drove it every day.  I still drive it to the trail for now, but that might change soon with the wife's new truck we ordered.  The good thing about driving to the trail is that I tend not to do stuff that is too stupid and break it too hard.
1992 YJ Sahara, 4.5 Rubicon Express ED Lift, 35" BFG MT, Custom Bumpers, SYE/CV Drive Shaft, OBA, Ford 8.8 rear, 4.10 gears, tie rod flip, 1"MML/BL
2002 KJ Liberty, 2" Lift, 31" tires/DD
2002 F-150 Harley Davidson 5.4L SC
2013 Explorer Sport
2006 Harley Road King Classic
1988 Honda Hawk GT

Offline Black-market

  • Trail Passenger
  • *
  • Posts: 28
Re: Yj to tj suspension fab question?
« Reply #12 on: October 13, 2012, 10:11:23 PM »
I'll probbly end up building my own 4 link
Some day I have access to a machine shop
And I'm a welder by trade and have some
Friends over on the west coast that are into
Baja and suspension there life but told me
Toll I had 10 grand don't come knocking
Lol so till my piggy bank hits that mark I was
Just going to mess around with ideas but
I guess all just leave it way it is and just get
Bigger tires. Any suggestions on them
I have 33" maxxis big horns but only got
15k on the befor they were cooked. Iv been looking
At baja claws what ever I go to is going to
Be a 35 or 36"

Offline Mr Rock

  • Administrator
  • Trail Master
  • *****
  • Posts: 1571
Re: Yj to tj suspension fab question?
« Reply #13 on: October 15, 2012, 11:03:12 PM »
Anyone driving a YJ as a daily driver needs to get their head examined! trust me I have one, if you have short commutes then maybe it's not so bad. I can drive about an hour with no problem to get to a trail but by the 90 minute mark I am done! and that's doing it once in a while not everyday!!

I don't think it is worth it to try to make a YJ "streetable".

lay off the drugs rock my jeep as the only thing i drove while i was in the navy just you need to be prepared to fix it over night when needed and i still drive it to work alot and will run it 80 miles on the highway to our farm (but it is double the cost compaired to pulling it on the trailer i love 4mpg on the highway but i get 8 in the city)  and i drove it half way across the country like 4 times my yj was the best dd i ever had and it is the only one i have kept for more than 3 years (but i am still young and dumb)


 "(but i am still young and dumb)" thanks for making my point, LOL, whatever year you make it back here I'd be happy to wheel with you again, we had a lot of fun!
'89, 4.2, NUTTERED, Team Rush, 4" Lift, 1" BL, 1" MML & HD shackles , Flat Belly Skid, SYE, 36 x 13.50s
XRC8, 150w KC's, Herculined, Tauras Elec Fan, Dual Batteries, Aussie in front, 8.8, TJ flares & Spool in rear, topless all of the time!

Offline gearhead1985B

  • Honorary Member
  • Trail Master
  • ***
  • Posts: 882
  • the Snozberries taste like Snozberries
Re: Yj to tj suspension fab question?
« Reply #14 on: October 16, 2012, 06:22:07 AM »
Anyone driving a YJ as a daily driver needs to get their head examined! trust me I have one, if you have short commutes then maybe it's not so bad. I can drive about an hour with no problem to get to a trail but by the 90 minute mark I am done! and that's doing it once in a while not everyday!!

I don't think it is worth it to try to make a YJ "streetable".

lay off the drugs rock my jeep as the only thing i drove while i was in the navy just you need to be prepared to fix it over night when needed and i still drive it to work alot and will run it 80 miles on the highway to our farm (but it is double the cost compaired to pulling it on the trailer i love 4mpg on the highway but i get 8 in the city)  and i drove it half way across the country like 4 times my yj was the best dd i ever had and it is the only one i have kept for more than 3 years (but i am still young and dumb)


 "(but i am still young and dumb)" thanks for making my point, LOL, whatever year you make it back here I'd be happy to wheel with you again, we had a lot of fun!

but suspension seats help a lot with the ride it does not make it a total pita rough riding sob and i hope to make mohawk weekend(next year i will have two weeks vacation) when i come up plus hit a couple of other trails like btc and mabell you guys will have plenty of notice or warning which ever you prefer i just need to get my copilots heart doctor to give the good to go thumbs up
"If you can read this, Thank a Teacher, if you can read it in English, thank a SOLDIER"

https://www.masterpull.com/Index.aspx
http://www.taboocustoms.com/