Project ROKTOY - Frame Mods

http:/www.4x4wire.com/toyota/projects/roktoy1/

Short Cuts

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By: Jay Kopycinski - 2/2002

The time had come to take another step in the evolution of my truck. Last year I had completed a tubular bed for it and was looking at more changes. I decided to go ahead and get rid of all the sheet metal and go with a full tubular body. Rather than add an exocage or more body protection armor, I decided to shed the body and try to shed some weight at the same time.


Here's the 1983 donor frame	Lots of metal brackets removed from frame

I started by buying a 1983 standard bed frame back in August 2001. Wheelbase of the new rig is planned to be about 106-107". There were lots of brackets and mounts on the frame that I had no use for. So, out came the cutting torch and saw, and I went to work shedding all the extra metal.


Frame stripped of extra brackets	Frame setup on dolly to begin work

After much cutting and grinding, and a little cleaning, here is what I ended up with. About the only mounts left are the front spring tubes, rear spring shackle hangers, gas tank mounts and horsecollar crossmember (later removed as well), and front bump stops. I set it up on this rack on wheels and started building on it.


2.5" dropped front spring mount	View of the dropped mount from the bottom

With the frame clean and ready for mods, the first thing I added were the front spring hangers. I dropped them 2.5" from the stock position using a crossmember similar to the one described in my Front Suspension article. I like running fairly flat leaf springs and the dropped mounts help me do that.


Rear hangers tucked up into frame	Another view showing front ramp angle

I'll be keeping my Mazda hybrid springs so I fabricated new front hangers from 3" x .180" wall square tubing and recessed them into the frame for improved clearance. I moved the front mounts back a little over an inch to increase the wheelbase and lay the shackle down a bit more.

New rear crossmember to box end of frame

I built a new, smaller rear frame crossmember out of 2" x 3" x .180" wall tubing and welded in a steel lug for a d-ring. Here you can also see the shock rear shackle hangers that were left on the frame.


Modified horsecollar crossmember	More room to tuck the exhaust up higher

Looking around under my truck I found that one thing that takes rock hits from time to time is my exhaust pipe. So....to raise it up higher so it is above the frame rail, I notched the middle frame crossmember and rebuilt it with an arch in it. Unfortunately, I later found that I needed to remove the horsecollar crossmember altogether and replace it with another crossmember. I decided to keep this info in this article thinking it might be useful for someone wanting greater exhaust clearance.


Added peanut shaped plate and upper mount	Photo showing box temporarily mounted

For crossover steering, I'll be using a standard Toyota 4WD IFS steering box. I drilled two holes in the frame and added a mount point for the third bolt above the frame rail. Both frame holes were sleeved with tubing and a peanut shaped 1/4" thick backing plate was added to the inside of the frame rail. The box bolts in place using three 1/2" bolts after the steering box holes were enlarged slightly.

This shows most of the frame mods completed prior to starting to setup the new engine mounts and then moving on to building the tube chassis on top of the frame. More to follow........