HZJ79 Trayback install, turbo, inercooler and exhaust manifold. (1 Viewer)

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Feb 1, 2004
Hi Guys,

I had last week off work so I decided to get to some work that I have been putting off since last fall.

Firstly, I needed to de-grease the inside of my intercooler and re-jig some of my intercooler piping, so I disassemled everything and found that my intercooler and piping was pretty oily, I cleaned all with a mild degreaser - I also cleaned the outside as well as there was some rust proofing on it. I also decided to pull my turbo off. For the heck of it I ported and polished my exhaust manifold, adapter plate, andexhaust side of the turbo - as well as the wastegate orifice and the muffler flange.

I also noticed that my internal wastegate was sticky with carbon - so I used a mild acid to clean it up - worked like a charm. Next year I will get rid of the internal wastegate and switch to a near maintenance free external wastegate. I don't like the exposed moving parts of the wastegate and actuator in this environment.

Secondly, I added a 3 inch mandrel bent stainless exhaust with aeroturbine muffler - a very nice and clean install - and sounds great - very quiet. It replaced a 2.5 inch stainless pipe with factory muffler.

There was a definate difference in power and EGT's, the truck really rocks now - egt's are very low and power is always there.

thirdly, the big nasty, heavy steel box on my truck has been driving me nuts, it is probably well over 1000 pounds and it looked like hell and affected performance. I have been trying to find a suitable replacement and knew I wanted aluminum but didn't want the usual checker plate redneck looking type. So I found a guy who happens to own an HZJ75 and an LJ78 and just happens to work at a manufacturing facility that makes flat decks for tractor trailers. All thier materials are extruded and their own patents. The facility is called Trebor Trebor Manufacturing Ltd Aluminum Truck Platforms

So I worked out a deal and got the materials needed and the guy offered to help me install it at my house. Check out the picks.
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The decking is extremely rigid, will never warp and i can put huge loads on if I want.
The floor gets a dry fitting and then the frame is brought to get TIG'd
The frame is just about finished and it gets mounted to the frame. We ended up using pucks for spacers, I can adjust the height of the bed at any time.
The bed is secured and the floor is installed - it is tongue and groove with stainless screws securing it.
The almost finished product coming in at about 325 pounds. I'll bring the truck in now and get it weighed to see how much weight I lost - I am thinking I shed about 700 pounds.

I quickly mounted the lights which I will later install in the rear trayback, I still have to build the sides and rear gate later this summer.

Next I will make the trailer hitch, instal the front locker, add the Q78 TSL swampers that should gine me a 35.5 or 36 inch tire. I also plan on ceramic coating the turbo and manifold at some point - just need the time.


The old box. My truck has gained 2 or more inches in the rear since the old box came off.
Great looking deck, are you considering any type of sides?

You got yourself a good little helper, cruiser mechanic in training.

The bed is secured and the floor is installed - it is tongue and groove with stainless screws securing it.
Ya, I'll put fold down sides and gate on it with the traditional type of bends and hinges. I'll probably also use my plasma cutter and cut off some of the side members to thin it out - I don't like the thick sides and thick reabr bumper.

As a side note I bought one of those chinese plasma cutters/TIG/Arc welders - the thing works great.

That little helper is my oldest son - he loves cruisers and goes wheeling with me all the time.


i love the toung and groove decking, great idea.

the stainless exhaust looks realy nice and clean espec for this area.

i agree with the heavy side look not fitting the look of the truck.

when you go larger tires you might find you have rub on full articulation so i would suggest dropping the rear stop blocks so that you clear the box by 1"

nice job Louis...
The tongue and groove allws the deck to flex, if it didn't it would just crack apart - pretty tough stuff to - might try them for bike ramps.

The exhaust i made it so I can remove sections as I am still not done with the truck, I will add a rear tank eventualy so I will need to reroute the exhaust. I was also off slightly on one section and I get some frame rattle on start up - so I have to cut and reweld it. Overall I like the way it runs and sounds as quiet as the stock muffler but with no obstructions - you can see right throught the aeoturbine muffler. I would have went straight pipe right out but I have to leave my driveway at 6am to go to work and I like my neighbours.

As far as clearance goes I think I have 12 inches from the 33's to the deck, I think I have 7 from the bump to the axle housing - will have to measure that.

Thanks for the comments.

Very nice setup . The t and g is a very strong deck material. A lot lighter and the 3" with areoturbine must make that 79 MOOOVE ! Good Job.
Nice job Louis;) I put this alloy tray on a few weeks back .Its a Unicorn brand and supposed to be good for 1500kg.
It doesnt have nearly as much support underneath as you have done but I only want it for camping and to be as light as possible.
Mine only has 2 long bearers running lengthways and connected to the frame mounts with s/s brackets sitting on some belt rubber.
My rear suspension was also raised about 2"
Maybe you could trim the sides back and add the rope tie downs like mine;)
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Thanks for the pic Ross, do you have a picture of the sides and rear? I want to cut the sides and add the tie downs - looks great.
Thanks for the pic Ross, do you have a picture of the sides and rear? I want to cut the sides and add the tie downs - looks great.

Only these until I find the battery recharger for the camera battery.


Im currently drawing some plans for a canopy to be made that sits on a false floor at the height of the sides(about 250mm above the tray)
Underneath I will keep my tyres,recovery gear, deep cycle battery, mounted compressor and tank and anything that doesnt need to be 100% water resistant.
On RH top of the false floor will be a bed for overnight stays on the road and the other side will be the kitchen with fridge,stove ,stereo with an awning.
Im going to fill the inside of the sides with flat aluminium sheeting so they can be used for making snacks on,reading maps etc.
I might also lift the tray off and install a big ass s/s water tank as there is a huge amount of wasted space near the muffler(check yours out)

I was going to get a canopy like the red one but with closer inspection they were not really suitable for my mods.
Looks real nice. I hope to have a stock toyota bed for my 75 in the not too distant future. I know its not as practical, but they really look nice on there.

I too have a heavy industrial bed on there now. 6 of us had to lift it to put it back on after I painted mine...
I got it from Trebor here in ottawa - see my first post for a link. Not sure if they would sell to the public but you can try. PM me if you can't.
my cab and chassis should be here this summer and i am prepping for the alum tray install. the one thing i did not like about the last ray was the actual decking material...this looks much more to my liking altough i will need to run the lengths the opposite way due to the main beam configuation on my design...

cheers and thanks M8

btw, care to head up to parry sound for a run this weekend? you can see the tractor tires in action...

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