ZUK mod with TJ coils (with pics)
#21
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4runnerFreedom: I personally think the coils are a bit too stiff for an unloaded pickup. That being said, I'm still running mine, so I guess it's not horrible. Sounds like these TJ coils are perfect for what you need...a temporary boost for your heavy load. They'll probably ride nicely in your loaded 4runner. Let us know how they work out for you.
#22
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just finished putting them in this morning. took all of an hour to do.
i have a slight rake in the rear now but i think once i've loaded it down for my roadtrip that will be eliminated.
drove it around the block on smooth roads and seemed OK. just so everyone knows the setup of my truck before doing this themselves:
1988 4Runner, rear springs have been re-arched with an extra leaf added. I have a full roof rack with basket and kayak carrier.
also, i removed the rear seats and built a sleeping/storage platform in the rear out of 3/4 plywood and 2x6. and all the storage space under the platform is full of camping gear and I have a 3" medium density foam pad approx Full size mattress size on top of the sleeping platform.
with that set-up i was at 11" from top of the wheel to bottom of the fender
now with that set up and adding the TJ springs (cut 4") I sit at 13 1/2" on the drivers side and 13 3/4" on the passanger side. Jumped on the back a few times to settle the springs in and no noises after that on my short test drive.
i'll be driving 4.5 hours one way today or tomorrow with a slight load in the back and possibly pulling a 13' camper trailer. that should be a good test to how the ride will be.
all goes well I'll be Cali bound in a couple of weeks with a tentative arrival the middle of September.
i have a slight rake in the rear now but i think once i've loaded it down for my roadtrip that will be eliminated.
drove it around the block on smooth roads and seemed OK. just so everyone knows the setup of my truck before doing this themselves:
1988 4Runner, rear springs have been re-arched with an extra leaf added. I have a full roof rack with basket and kayak carrier.
also, i removed the rear seats and built a sleeping/storage platform in the rear out of 3/4 plywood and 2x6. and all the storage space under the platform is full of camping gear and I have a 3" medium density foam pad approx Full size mattress size on top of the sleeping platform.
with that set-up i was at 11" from top of the wheel to bottom of the fender
now with that set up and adding the TJ springs (cut 4") I sit at 13 1/2" on the drivers side and 13 3/4" on the passanger side. Jumped on the back a few times to settle the springs in and no noises after that on my short test drive.
i'll be driving 4.5 hours one way today or tomorrow with a slight load in the back and possibly pulling a 13' camper trailer. that should be a good test to how the ride will be.
all goes well I'll be Cali bound in a couple of weeks with a tentative arrival the middle of September.
#23
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the coils worked great!! if it weren't for the coils i would not of been able to bring the gear i brought. i was 4wheeling through the black hills and some spots in utah but nothing too serious because i was loaded down pretty heavy. but there were a few times that a really tweaked those springs on some uneven ground and nothing popped out.
i wasn't able to pull the trailer. a little too much for the 22re, and since i was going through montana i decided to leave it behind. no issues the entire trip except i had to get the front wheel bearings repacked.
i've been in cali since the middle of september. now that the load is much lighter, it certainly is stiff and bounces around a bit as i'm driving around these mountain roads. but as toyNG stated, not bad enough for me to take them out.
highly recommended by me.
i wasn't able to pull the trailer. a little too much for the 22re, and since i was going through montana i decided to leave it behind. no issues the entire trip except i had to get the front wheel bearings repacked.
i've been in cali since the middle of september. now that the load is much lighter, it certainly is stiff and bounces around a bit as i'm driving around these mountain roads. but as toyNG stated, not bad enough for me to take them out.
highly recommended by me.
#24
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two questions on this approach to the mod:
1) would it be possible to counter the stiffness of the springs with a different type of shock (adjustable, etc.)?
2) are there other springs with the same dimensions but with a lower spring rate? i could see how using springs meant to hold up a heavy TJ front end would end up being too much for an empty toyota bed. there's gotta be something else with comparable dimensions and a less intense spring rate.
1) would it be possible to counter the stiffness of the springs with a different type of shock (adjustable, etc.)?
2) are there other springs with the same dimensions but with a lower spring rate? i could see how using springs meant to hold up a heavy TJ front end would end up being too much for an empty toyota bed. there's gotta be something else with comparable dimensions and a less intense spring rate.
#25
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we took oe tj front coils and trussed up the rear axle. installed them side by side off of the center diff up to a support we ran between the frame rails. this gives the extra stiffness we need for hauling supplies, dogbox, and hounds. also provides the same flex on the trails as having no helper springs.
#26
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we took oe tj front coils and trussed up the rear axle. installed them side by side off of the center diff up to a support we ran between the frame rails. this gives the extra stiffness we need for hauling supplies, dogbox, and hounds. also provides the same flex on the trails as having no helper springs.
Last edited by ZUK; 01-07-2011 at 08:23 PM.
#28
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trying to get this straight in my head.
TJ coils....fronts would need to be trimmed to give a length of 12''.....right.
in the end what exactly are we looking for???? a 12'' spring with a ??? 4 or 5'' INSIDE DIAMETER by 12'' and a rating of what kind of pounds?
I like the post about looking for the rear coils because they don't need to be trimmed...less fab work equals happy me.
so this thread gets a BUMP because I am considering this.
TJ coils....fronts would need to be trimmed to give a length of 12''.....right.
in the end what exactly are we looking for???? a 12'' spring with a ??? 4 or 5'' INSIDE DIAMETER by 12'' and a rating of what kind of pounds?
I like the post about looking for the rear coils because they don't need to be trimmed...less fab work equals happy me.
so this thread gets a BUMP because I am considering this.
#29
Being a jeep guy for longer than I have been a toyota guy, let me clear a few things up
Stock TJ fronts and XJ fronts are the same and interchangeable.
The front Spring rates only vary by accessories (AC etc) and are around 145 to 155 depending on who is making them (if you get aftermarket stock coils)
Rears are 200lbs for a regular TJ, not sure on an unlimited (long jeep)
As for other jeep springs, I added the 2 middle leafs from a 78 cj7 to my rear pack, They are the same width and just a bit more arch. Rides great and put it back about stock height or just above
Stock TJ fronts and XJ fronts are the same and interchangeable.
The front Spring rates only vary by accessories (AC etc) and are around 145 to 155 depending on who is making them (if you get aftermarket stock coils)
Rears are 200lbs for a regular TJ, not sure on an unlimited (long jeep)
As for other jeep springs, I added the 2 middle leafs from a 78 cj7 to my rear pack, They are the same width and just a bit more arch. Rides great and put it back about stock height or just above
#30
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i know old thread, but i picked up some tj coils yesterday.
looked under the truck and half the bumpstops are cracking off the plate. gave it a slight tug and the whole thing fell apart.
So I'm going to have to weld on some cups to retain the axle side of the coils before i can do this mod.
just giving everyone a heads up. take a look at the condition of your bumpstop/metal interface. you dont want that spring flying out when the rubber cracks.
looked under the truck and half the bumpstops are cracking off the plate. gave it a slight tug and the whole thing fell apart.
So I'm going to have to weld on some cups to retain the axle side of the coils before i can do this mod.
just giving everyone a heads up. take a look at the condition of your bumpstop/metal interface. you dont want that spring flying out when the rubber cracks.
#31
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iTrader: (1)
i know old thread, but i picked up some tj coils yesterday.
looked under the truck and half the bumpstops are cracking off the plate. gave it a slight tug and the whole thing fell apart.
So I'm going to have to weld on some cups to retain the axle side of the coils before i can do this mod.
just giving everyone a heads up. take a look at the condition of your bumpstop/metal interface. you dont want that spring flying out when the rubber cracks.
looked under the truck and half the bumpstops are cracking off the plate. gave it a slight tug and the whole thing fell apart.
So I'm going to have to weld on some cups to retain the axle side of the coils before i can do this mod.
just giving everyone a heads up. take a look at the condition of your bumpstop/metal interface. you dont want that spring flying out when the rubber cracks.
If there is a very loose fit then you can "extend" the lower custom mount that you are fabbing up and in that way take up the air gap and keep the coils there under any situation.
ZUK
#32
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I'll try to remember to take some pics before and after, usually not too good at doing any before pics.
I did jack up the rear until both tire drooped, and there is no way the front (skinny) TJ coils will pop out unless you cut them down. you will absolutely need spring compressors to put them in uncut. ( i think they were about 17" tall uncut)
I'll try this first and see how much lift I get, as I plan on removing the blocks I have there now.
I do have the rears (wider ones) I can take a look at too, but I plan on using the fronts.
I did jack up the rear until both tire drooped, and there is no way the front (skinny) TJ coils will pop out unless you cut them down. you will absolutely need spring compressors to put them in uncut. ( i think they were about 17" tall uncut)
I'll try this first and see how much lift I get, as I plan on removing the blocks I have there now.
I do have the rears (wider ones) I can take a look at too, but I plan on using the fronts.
#33
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as i thought, forgot about camera till later...
but anyways.
cut 1.5 coils off the constant diameter side, ended up being about a 15" length.
used a coil compressor for the coil, and a jack to spread the leaf from the frame to shove them in.
removed the 4" blocks and now sitting roughly the same height, maybe a hair shorter.
rides stiffer obviously, but for me its just right, makes it feel like a truck, not a caddy.
and more capacity is good for me too
but anyways.
cut 1.5 coils off the constant diameter side, ended up being about a 15" length.
used a coil compressor for the coil, and a jack to spread the leaf from the frame to shove them in.
removed the 4" blocks and now sitting roughly the same height, maybe a hair shorter.
rides stiffer obviously, but for me its just right, makes it feel like a truck, not a caddy.
and more capacity is good for me too
#34
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iTrader: (1)
appreciate the update. I'm a little surprised it rides more firm.....I kinda figured that with the leafs now not on the overload that it would be somewhat softer....but I guess that's where the coil employed can effect things. I bet you will never experience sag EVER again....until you change the suspension in the future.
#36
Just did this on my 89 4runner, used TJ front springs with about 4" (2 coils) cut off. Love the new height, got new shocks too (Monroe) and my ride is MUCH better...no more bottoming out! My only problem is that the springs are STILL popping and making a racket on turns...thinking I may have to secure them somehow, but having trouble thinking of how.
#38
I would like someones input on this. I have an 85 pickup 4x4. I have a custom made flatbed on the truck. I put new springs up front with a total of a 4 inch lift, a rear add-a-leaf. on the rear springs i have about a inch or so before the pack is resting on the overload leafs. I had 31 in tires on the truck with approx 5 inch of clearance between the bed and the tire, now i have 33's with approx 2 inches of clearance. Would this option help me out? would it be just a bandaid type fix? The reason i ask is becus of limited axle travel.
truck with 31's
truck with 33's
truck with 31's
truck with 33's
#40
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Just did this on my 89 4runner, used TJ front springs with about 4" (2 coils) cut off. Love the new height, got new shocks too (Monroe) and my ride is MUCH better...no more bottoming out! My only problem is that the springs are STILL popping and making a racket on turns...thinking I may have to secure them somehow, but having trouble thinking of how.
https://www.yotatech.com/forums/f116...-notes-243688/
edit---just re-read it and realized that you are using TJ coils..... scraping noises on the upper end could be an issue with the metal to metal tensions. No easy way to make the upper large coil diameter fit correctly unless the factory steel bracket is cut off 100% and something else welded or bolted on.
Last edited by ZUK; 11-29-2011 at 10:20 AM.