Builds The "Everybody loves a build thread" BJ74 Trail truck build Thread

[Radd Cruisers]

The longer shackles that came with the truck in the rear have two sets of holes. The lower hole is really too far out there (15 cm on centre), but the upper hole is about right (12 cm on centre). I pulled out the rear shackles, took them over to the chop saw, and cut them off just at the top edge of the lower hole to yield shackles with pin centres at 12cm apart. This is still a fairly long shackle, but it works nicely with the springs and give a touch extra added lift.

Photo 1: shackles as they are coming off...

Photo 2: during my camping trip on the August 1st long weekend to a little lake a couple of hours from here, you can see that the shackle angle is near vertical, but still okay with the truck partially loaded.

 

[Radd Cruisers]

Installing the rear spring was a pretty straightforward effort. They are made to fit the 70 series so they went in very easily. The only real change I made was the modification of the shackle to the longer ones I already outlined.

The OME shocks, in my experience, always come up short when you're looking for maximum wheel travel. In light of this I didn't pay too much attention to their offerings other than to look down the list of what I had, and the various specs, to indeed confirm that they were not going to suit my project.

In the end, used some rear shocks from a full sized Dodge pick up that we removed while installing a leveling kit that came with new shocks. The Dodge shocks are an inexpensive gas shock, and are quite long. The rear shock mounts came up at roughly 63.5 cm extended, and these shocks fit with room to spare. The only modification I had to make was to remove the sleeved bushings and re-use the stock Toyota split bushings that came off the old shocks.

The other thing that I did was to replace the too short stock rear brake hose with one that was longer. The one I ended up using was a little over 43.5 cm long (Napa part number 38796).

The axle breather tubes will need to be addressed in the future...

 

[Radd Cruisers]

When it came time to install the CS017RAs in the front, I knew that I was going to be in for quite a bit more work.

The spring length of the CS017Rs from the rear mount to the centre pin is the same as the CS006F (and, of course, the stock front springs), so that part of it was quite easy. It would have been nice to have run the axle forward a couple of centimeters, but I really have no plans to run tires over 33" diameter, and so moving the axle is not a requirement.

The issues that arose were as follows:

- the sway bar links were too short - by quite a bit.

 

[Radd Cruisers]

- The shocks were Wayyyyy too short...

 

[Radd Cruisers]

- The shackle angles were okay when things were hanging...

 

[Radd Cruisers]

- But way beyond acceptable when the weight of the truck was on the springs....

 

[Radd Cruisers]

A few solutions:

- The sway bar was an easy fix - and removing it solved the problem quite nicely.

- The shocks were taken off, and this was put aside for measuring for fit later on.

- The shackle angle got me thinking... how about another set of mounts? So I went out into the yard and dragged in a piece of BJ60 fame, fired up the plasma cutter and cut the tubes out of the front spring hangers. Once I had the parts cleaned up and in my hands, I took them back to Coleman and sized up the situation... That was going to take too much time and be way too complicated. They got put back on the bench.

So I sat back, took a few sips from my beverage, scratched my head a few times and made a few measurements...

 

[Radd Cruisers]

Next, out came the soap stone and I marked things up...

 

[Radd Cruisers]

Next came the Makita grinder armed with a zip cut... and short work was made of removing the spring hangers along a (relatively) straight line.

I then moved the mounts forward a few cms and tacked them into place with my hot glue gun.

After a few attempts (and really, I did use some pretty good numbers for my first tacking, but the longer shackles played with that a bit), I got it right and laid in some good beads all round.

 

[Gib009]

What springs are they in the front mate? I have rear springs up front and the shackle angle wasnt that bad..

 

[roscoFJ73]

Hi John,

Another couple of questions mate

In your pics there is a 74 with a rack that looks like its mounted to the gutters. Do you know the specs on the load this rack
can carry? Would it handle 50kgs (Roof Top Tent) whilst 4x4ing? I'm looking at mounting my rack the same way if the frp can
take the stress and weight.

Cheers mate.

Rhino or Rola sell that kind of roof rack and I think they are good for 200kg. Not sure if thats offroad though.
I think it would more than enough for your tent and a spare. A light weight plastic table would also fit up there nicley.

 

[boogie74]

Rhino or Rola sell that kind of roof rack and I think they are good for 200kg. Not sure if thats offroad though.
I think it would more than enough for your tent and a spare. A light weight plastic table would also fit up there nicley.

Hey Mate,

I reckon the rack would carry the load no probs its just that the frp top might not hold up where the rack clamps onto it.
I think the 30kg limit John has on his compliance plate refers to the load the roof can take, not the rack. The gutters on my
roof look like they are riveted on and then fibreglassed over. I think the constant vibration of off road traveling might
break the gutters or split the frp. Also the gutters/mounting points are a fair way apart with no support in between. Ron R
reckons his frp top cracked under the pressure of the rack and although his is a different shape to mine I would like to
avoid stressing the roof. I'm leaning toward the exo rack idea. The pipe is cheap enough to experiment with, probably 30
bucks worth of pipe and some flat to weld and tap the chassis to bolt it on. I'm going to get onto this real soon. In a week
or so when work and uni ease up I'm going to get on it.

Having said that. My local TJM dealer told me the frp was good for 140kg. But Im not so sure.

Slipping a table underneath the tent base is a great idea. I have seen slim line 50lt water tanks too which would be good
up there but I'm not keen on adding to much weight up high. I was going to post a pic of the water tank but cant find the link right now.

Sorry, for the rant/hijack/thinking to much.

Have a good 1.

 

[lshobie]

You mentioned the poor engineering of the spring lengths, I have a response from ARB about why they did it that way - just have to find it It is right from the spring engineers. Turns out one of the engineers who designs lockers and the new ARB compressor is a Canadian living in Australia

EDIT: found the info, basically the engineers state that the springs are designed to be loaded. If you have a 450kg load spring then when you have 450kgs in the back it will work exactly the way it is supposed to - ie. the way you buy the springs - to carry stuff. If you remove leafs then you overload the remaining when you do load them up. When loaded the shackle angles will be exactly the way they are supposed to be.

I have put OME kits on HZH73's and I thought they were too small as well - the shocks are at full extension and you have to almost compress the spring slightly to get the shackle on - but if you think about thier explanation then it makes sense. When I loaded the vehicles up they were perfect.

 

[jericho]

Coleman's Wheels

I was looking at putting on the same wheels, early 80 series - correct, 15 x 7 with a 4.5" backspace? What did you do to get them to fit? Are they bolt on, or did it require a spacer? What size 33" are you planning on running?

 

[Radd Cruisers]

Testing the 24 Volt Warn VTC air compressor

I had a bit of spare time today so I decided to test Warn's claims about the VTC air compressor:

I am testing the 24V version of the VTC. I paid for and personally own the compressor and have received no sponsorship or any other considerations from Warn or any of its affiliates.

From the Warn website -

Warn Industries - Air Products: WARN Air-Power VTC

"With an abundance of power from its high-horsepower fan-cooled motor, V-twin configuration, and large one gallon integrated intercooler and reservoir, the Air-Power VTC is the highest-performance compressor in the WARN Air-Power lineup. The VTC is ideal for powering air tools, rapidly airing up everything from tires to rafts, powering air suspension systems, and just about anything else that needs air. It comes with a removable carrying cage so you can easily transport it or hard mount it to a vehicle or trailer. A pressure cut-off switch turns the compressor off when it reaches 100 PSI and back on at low pressure. Add to this a quick-connect hose outlet, and you've got an ultra versatile compressor. With all this power and all of these features, the VTC is a force to be reckoned with. "

Power: 12V DC motor
Maximum Pressure Rating: 100 PSI (690 kPA)
Airflow Rating: 20 CFM @ 0 PSI; 8 CFM @ 90 PSI; (566 l\min @ 0 kPA, 226 l/min @ 620 kPA)
Intercooler/Air Reservoir Size: 1 gallon (3,78 liter)

I did three basic tests -

1. Tire inflation using Coleman (my trail-rig BJ74) as the guinea pig since it has 33 x 12.50 R15 tires and I have outfitted this truck with a 350 Amp accessory plug for a second winch and the VTC compressor.

2. Running a 1/2" commercial grade impact gun to remove lug nuts.

3. Running a high volume die grinder continuously to check total air flow.

=====================

Tire inflation -

I deflated a slightly warm 33" tire from 35 PSI to 5 PSI and measured the inflation pressure at the low end with an accurate low pressure gauge.

I attached a Napa inflator with gauge attached to the compressor and timed how long the re-inflation took to get back to the 35 PSI mark. The compressor was hooked up to the truck running at idle (about 800 rpm). The air hose on the inflator is only 1/4" ID.

From 5 PSI to 35 PSI took 1:31.0 and I stopped adding air to the tire on three occasions to check the pressure (total time to do that was probably in the 5 second range).

Performance thoughts: pretty much what my shop compressor would do given the air hose restrictions and time to check the inflation pressure. My shop compressor is capable of 18.5 CFM at 90 PSI. I think this is outstanding performance for a relatively small air compressor package, and is certainly much faster than other small electric air compressors used for similar purpose.


Removing lug nuts -

I attached a Mac Tools AW434 1/2" impact gun to the compressor via a 50 ft long 3/8 air hose. The gun operated extremely well for the short bursts that were required to remove the 6 lug nuts that hold on the wheel I tested.

Performance thoughts: I would have no issues using this compressor for these types of jobs, and I'll start packing my air tools again when I go out on longer trips. The AW434 is a full-sized commercial grade impact gun and uses a considerable amount of air.


Continuous use of a high volume requirement air tool -

I used a Mac die grinder hooked up the Warn 24V VTC air compressor via the same 50 foot air hose as above. The grinder worked at full speed until shortly after the compressor started, and then the performance dropped off as the compressor tried to keep up with the air volume required.

Performance thoughts: This was an unfair test in some ways as die grinders are major air hogs and the Warn VTC has a relatively small air reservoir, even with the length of air hose I was using. The performance of the die grinder was reasonable, and it could certainly get the job done but at slower speed than a large shop compressor.


Overall -

I am very pleased with the Warn VTC and its overall performance. The VTC is a somewhat large-ish package to be carting about, but having an abundant source of air that does not require under-hood modifications is very much worth it.

The compressor would certainly operate continuous use air tools much better if additional storage volume was added via under-body air tanks. On my old BJ42, I used a Chrylser V-twin AC compressor for many years with a 5.5" x 18" air tank and it had excellent performance - though the installation was time consuming. The VTC is comparable in many ways with the exception that the storage pressures that is working at were much lower than what I managed with my Chrysler unit.

 

[Radd Cruisers]

I was looking at putting on the same wheels, early 80 series - correct, 15 x 7 with a 4.5" backspace? What did you do to get them to fit? Are they bolt on, or did it require a spacer? What size 33" are you planning on running?

The wheels in the first pictures are a 16x6JJ Toyota wheel that comes with a lot of these trucks from Japan. They do need a little more backspacing otherwise the tires rub against the inner fenders in the rear. The tires that are mounted on those rims are 285 75 R16 BFGs.

I have the 33x12.50s mounted on some run-of-the-mill white spoke steelies. They don't have quite enough spacing in the front or rear as the left tie rod end (it's a RHD BJ74) will rub against the tire wheel steered to the right, and the rear tires will rub the inner fenders off-road.

I am eventually going to be using some 255x85R16s on the Toyota wheels and add some wheel spacers. I will probably settle on 1" of spacing and may have some steel units made up as I am not a very big fan of the aluminum units... though cost may end up being a deciding factor.


~JOhn

 

[Radd Cruisers]

What springs are they in the front mate? I have rear springs up front and the shackle angle wasnt that bad..

As mentioned previously, I installed rear springs at both ends. The front got CS017RAs and the rear got CS017RBs. The difference between the A and B springs is 20 mm of free arch, with the A springs being the ones with the greater arch.

~John

 

[Radd Cruisers]

You mentioned the poor engineering of the spring lengths, I have a response from ARB about why they did it that way - just have to find it It is right from the spring engineers. Turns out one of the engineers who designs lockers and the new ARB compressor is a Canadian living in Australia

EDIT: found the info, basically the engineers state that the springs are designed to be loaded. If you have a 450kg load spring then when you have 450kgs in the back it will work exactly the way it is supposed to - ie. the way you buy the springs - to carry stuff. If you remove leafs then you overload the remaining when you do load them up. When loaded the shackle angles will be exactly the way they are supposed to be.

I have put OME kits on HZH73's and I thought they were too small as well - the shocks are at full extension and you have to almost compress the spring slightly to get the shackle on - but if you think about thier explanation then it makes sense. When I loaded the vehicles up they were perfect.

In my experience installing OME springs - and I have done quite a few over the past couple of years - the shocks are always too short, and the shackle angles are always too steep. The excuse that they are designed to work properly at full rated load is a lame one, since most people drive their Land Cruisers most of the time with far less than the max rated load.

All shock manufacturers will tell you that you should never bottom out a shock, and that you should never top out a shock. The OME shocks will severely limit droop travel in almost all cases as they are too short at full extension. And I don't believe that it's good thinking to load the suspension so that you can get the shocks to fit on to their mounts during installation.

In my calculations, the springs will have to be fully flattened out to get a decent shackle angle. For ride comfort, a vertical or near vertical shackle angle is going to produce a much rougher ride than what the springs are capable of delivering than if the shackles had some more angle to them.

The other issue that regularly comes up with the OME Dakar springs is that the steel sleeves in the spring eyes do not fit well and slide out of place easily. The movement of the bushing dramatically increases bushing wear, causing the edges of the bushings to wear off. I had a set of springs in for a Tacoma recently and the sleeves were falling out on their own, and so much so, that they were shipped with a zip tie holding them in.

I still think the OME springs are good value, but I really do not agree with the Corporate line that the Dakars are the same or better quality as the Australian made springs. The reason they went with springs made off-shore was to reduce production costs - but the effect of this was to increase the bottom line for ARB, and to (possibly) keep their springs priced favourably for the consumer.

In any OME leaf spring suspension system, the springs represent good value for one's money, but the rest of the hardware is somewhat over-priced.

Because I wanted to have a lot more movement out of my suspension, I decided to do things my own way. The shocks are not limiting droop, and the ride quality seems to be pretty good. The small amount of off-roading I have done with the configuration indicates I need to do a little tweaking yet (tires hitting mud flaps, and a few other small annoyances) before this is a perfect SUA set up.

~John

 

[Radd Cruisers]

A little bird said you might be running a extreme valve body?


Good build, I really wanted that truck when I first seen it come into the shop. It should work crazy good with the auto and cable lockers.


Rob

 

[BeratE]

Updates?