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onesunJ10 08-31-2009 06:25 PM

Projekt Heavy Low J10
I've wanted to do a build thread for a while. I started the project in high school (~4 years ago) after I wrecked my first J10 at Truckhaven.

It started as a bone stock 77 J10.

It almost immediately got a simple 4in lift and some 37s. Oh how she used to be clean :D

In late 2006 I took it to Hollister and broke the rear Dana 44. Snapped a shaft, bent the flange, twisted the other splines and chipped some ring gear teeth. 1/2 ton stuff just wasn't up to snuff!

This was the beginning of the end. I joined the Polygoats Offroad Club up here at Cal Poly San Luis Obispo and my 1ton pipe dreams soon became reality. Hanging with these guys changed my perspectives a little bit...

My first major part of the project was the rear axle swap. Here is the thread where I did the 14Bolt swap...

So. Heavy Low is born.

j20brett 08-31-2009 08:34 PM

do we get the rest of the post or is this it? :confused:

Good lookin truck i just want to see the end :)

RTFM 08-31-2009 10:22 PM

It's an Easter egg hunt, the above thread has a link, maybe the follow on post has another link and so on.

I dig the lifted pic. Sweet.

onesunJ10 08-31-2009 11:01 PM

That one took me awhile, got burned out tracking down pics :D

So, back to the build. In summer 2007 I found a Dodge 60. It needed some work.

Upgradessssssssssss \m/ :D \m/

Some shackles i made

Plated knucks

Broached my 30 spline flanges to 35 spline.


Now, for my first mistake. I will never run a long spring in the front again. I tried to run an F150 rear pack bastardized with multiple extra leafs for extra spring rate. Ultimately, these are too long, floppy, and not stiff enough. This was soon righted with a set of 52" Blazer rears. Great spring IMO.
The 57s. FAIL

Too tall with 57s

One thing that I ended up paying some serious attention to was what my ideal spring rate would be. I didnt want to screw up again. Using the idea of "ride frequencies", vehicle weight, and wheel base, I was able to come up with a ball park ideal spring rate for an dual purpose rig...(Desert prerunning/Rock Crawling). My basic frequencies were 1.2Hz for the front and 1.5Hz for the rear. My spring rate needed to be 265in-lbs. The 52s I got were 263. Pretty close. I can elaborate more on the subject, but it's too much to do so here.

Shackle reversal and plated in new front hangar....

Then there was the first ever trip to the Hammers!!
January 2008

onesunJ10 08-31-2009 11:40 PM

A cleaner picture of the rig from one year ago...

Last summer I got the axles re-geared to 5.13s and mounted some 2.5 x 14 Sway A Way "Rust" Runner shocks.
Unfortunately my comp crashed and that folder wasn't backed up. So no build pics on front shock hoops :(

Limit straps. The front end cycles about 13in.

I also built a front bumper.

My gussets throw horns \m/

Annnnd. New Years Hammers Trip 09. The last time she's been on the dirt.

^^Putting my driveshaft back together.

SO. Now we are almost current. I'm doing some fun stuff this summer. It's gotta be done by Sept. 11th for a end of the summer Hammers trip. Stay tuned.

Casey 09-01-2009 05:59 AM

:thumbsup: :thumbsup:

Sweet rig!

Good looking fab work!

AlsChopShop 09-01-2009 09:43 AM

nice work!

i don't understand why everyone goes with grabber green though.... :confused:


jaber 09-01-2009 10:38 AM


Originally Posted by AlsChopShop
nice work!

i don't understand why everyone goes with grabber green though.... :confused:


Whats wrong with Grabber Green???:huh:

Thanks for the pics, your truck is an inspiration....

Casey 09-01-2009 10:45 AM


Originally Posted by jaber
Whats wrong with Grabber Green???:huh:


brubakes 09-01-2009 10:52 AM

I'm liking the build! :D

orangecherokee 09-01-2009 02:11 PM

love the truck. this is something I'd like to do in the future. keep the updates coming. I'm interested in how you came up the spring rates.

onesunJ10 09-01-2009 11:20 PM


Originally Posted by orangecherokee
love the truck. this is something I'd like to do in the future. keep the updates coming. I'm interested in how you came up the spring rates.

I need to talk to my buddy, as he is the one who explained the theory and basics to me. I'm missing some of the details.

But basically if you know the vehicle weight at each contact point (LF, RF, RR, LR), and you know the ride frequency you want to achieve, you can attain a spring rate that works well in most situations.

The front (mine is based on 1.2Hz) and the rear frequencies (mine is 1.5Hz) are meant to make the truck ride better at speed when the suspension is being cycled. As you drive, lets say you hit a speed bump. Your front will start to oscillate at 1.2Hz and your rear will hit the same bump 8 feet later. The goal is for the two oscillating suspension waves to match each other. You can look at is as your front and rear bumpers moving up and down at the same time. In order for the second (rear suspension) wave to catch the first wave, it must have a faster frequency. Once they are matched, the truck bounces in a much more controlled manner. However, you need to control this.

In my opinion, you need good shocks for this to work to your advantage. A properly tuned shock will dampen and control the oscillations, or bounce. I want my truck to hit a bump, oscillate once, then be back to a steady ride.

I'll post more as my memory is refreshed.

Not sure if any of this makes sense!

onesunJ10 09-01-2009 11:30 PM


Fred Williams old 39s

Some Rust A Ways for the rear. 2.5"x14" Piggy Smooth Bodies. I did an initial re-valve on them. Heavier rebound. It's a valve stack of .010s on both compression and rebound. We'll see how they end up working in a couple weeks.

j20brett 09-02-2009 09:48 AM

Shock pron. I love it.

Stuka 09-02-2009 05:50 PM

Love your truck. Is that a factory color? I really like it.

mike12 09-03-2009 06:16 AM

looks like a j10 or j20 or big fuggennnnn green jeep thing

onesunJ10 09-06-2009 03:17 PM

Finally finished my rear shock hoops. Took a couple weekends.

Cut out old cross member and shock towers.

Bent the upper hoops...


Added a new tube near old xmember.

Mocked up.

I added a tube in between the hoops and tacked on some BA shock tabs I got from Poly Performance.

"Sure it's safe! I welder'd it myself!"

I'll snap a pic once i get the new shocks in.

Right now I'm pulling my transmission output shaft :thumbsup:

Only 5 days til she'll be at the Hammers!

onesunJ10 09-15-2009 02:22 PM

Dovetailed J10?
So, about a month ago i started to dovetail my truck. I finished the dovetail but could never get a good look at it because the rig was backed into a corner on my sideyard. Check em out.

trcooperone 09-15-2009 02:28 PM

Nice work! You did a real clean job.

lost1 09-15-2009 05:32 PM

Wow. Like others have said, nice work. I'm going to have to remember some of this stuff later on down the road.

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