SOA conversion on Hilux axles

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slunnie
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SOA conversion on Hilux axles

Post by slunnie » Tue Mar 07, 2017 10:24 am

The rear axle I've just started with. This has been removed and will be replaced with a stronger Hilux unit with 1" further offset Landcruiser 15x8 sunraysia rims. The Rover axle had 4.7 gears, the Hilux has 4.88 gears. In the process of this conversion the end result will be a lift of about 6", though with an axle set that is a lot stronger and wider, being all up about 8" wider from outer to outer. The perchs on the Hilux axles are too wide for the Landy and need to be replaced with ones in a narrower position. The spring pack is 8 leafs and 1200mm long which is the same measurement that allows me to run cut down Hilux springs one day, probably giving more travel and will give a greater wheelbase than the current 88". The lowest 4 load leafs have been removed and the rear packs reinstalled. This hopefully will improve articulation significantly which is what the aim is - offroading ability, and also reduce the ride height. The aim is to keep the suspension soft and even front to rear to maintain a low CofG when articulating. The new axles go under the springs instead of on top which makes installation easy.
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Here is the Salisbury that came out. Not a bad sized diff really.
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What amazes me is that LR use this diff which could no doubt be used in a supercharged chev V8 truck on 44" bog tyres reliably all day by using a 9.5" Crown wheel (with a 1.5" 35 spline 1/2 shaft conversion), and then they stick axle 1/2 shafts into it made from mild steel fencing wire - literally. Wow, the strength of a weak diff and the clearance of a big diff. Rolling Eyes

AstalaVista baby! Twisted Evil You're outa here

The original 8 leaf pack has a rate of about 160lb/in
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though the name of the game here is articulation. 160lb/in is already soft, though I've taken the 4 lowest load leafs and removed them.
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Hopefully this will allow a significant generation of up travel, especially with sprung over axles which offer a lot more space for this. My other hope is for the springs to sit flatter than usual to reduce ride height when its all together again.
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Fabricated the rear spring perches this afternoon. Used 65x65 RHS and 150 long for each perch. Holesaw at 65mm for the axle tubes and a 16mm hole for the perch location on the spring.
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This afternoon it was time to prep the axle!
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All of the unneeded bits like brakelines and brackets were removed and ground flat. The surfaces that required welding for the spring perches was also cleaned of paint.
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It's surprising how narrow the chassis is in relation to that of the Hilux when comparing the perch positions. The narrower perch seperation of the Landy means in theory it can run a stiffer spring for load carrying in comparison to the Hilux, yet have improved articulation and increased body roll. This is assuming all other things being equal.
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Definitely narrower spring perches!

I thought oh well, I should try the axle on for size and after a brief dilemma trying to pick the thing up I ended up dragging it out of the shed under the Landy. With a fiddle here and there the perches went on (loose fit) and the whole lot went together.

I was a little surprised at the lift, with it being as low as it is. When I sprung my trailer over it gave a lift of about 6 or 8 inches if I recall correctly, though the Landy measured up at a solid 2" maybe a touch more with the axle conversion. I did pull 4/8 leafs out of the spring pack so it looks like it may have done the trick. The other benefit is that it looks like the pinion angles will be sweet! The resultant track is also about 8" wider overall. Not bad, 2" up, 8" out! Very Happy Hmmm, sideangles! Twisted Evil
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The leaf packs are looking nice and flat compared to the usual Landy camber.
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It looks like pinion angles and tailshaft lengths will be fine also. I'll jack the axle angle around before welding the perches into position. That pinion flange will have to come off and get machined to fit the factory Landy tailshaft.

Cold bent and 1/2" drilled shock mounts made from 50x6 MS. These are for axle mount and will take eye style shocks. Old factory D2 or old 10" GU Patrol rear Rancho's hopefully will get bolted to these.
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Today I pulled the axle out again and welded the spring perches before relocating the axle.
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I ended up plating around the axle with some 3mm bar under the U-bolts to make them fit snugly. The U bolts were flexed slightly to line up with the spring plate and assembled. I swapped the factory LR spring plates to the other side which puts the shock mounts to the rear. This has allowed me to use the std shocks and hopefully gain some travel by having them sit at a 45 degree angle. The shock action will of course be reduced by this as a trade off.
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Now onto the front end and removal of the axle.
This is it before I took to it with the rattle gun. Twisted Evil
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This is the lump of an axle that came out. With all of the steering knuckles etc, I could hardly pick this thing up. Skull drag the bugger out of the way. Laughing
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...and this is how the Landy was left looking. Some of those bolts were really hard to undo, 1 of the U-bolts even tricked the rattle gun! Angle grinder to the rescue. The angle grinder can pursuade anything that it touches. Laughing The springs are very short in comparison to the rear, and as a result I seriously doubt that I will be able to gain the same level of travel without replacing them with a longer set. This is a budget buildup so I'll work with what I've got. There are 9 leaves in the pack, and I will later remove some leaves like what was done in the rear. I'll end up leaving 4 or 5 leaves in the end and see how it goes. The back is so flexy at the moment it doesn't allow the front to work at all, so I will have to find some type of balance. Being short leaves I'll probably reduce them to 4 leaves full length leaves intially and see how it goes. That should leave a spring rate of around 110lb/in from the factory 220lb/in. It also looks like the front prop shaft may not have enough travel in it as it is for the travel setup which is being produced. I'll have to have a think about that later and do some research.
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The Hilux axle needs a fair bit of prep before going in. Unlike the rear, the perches are in the correct positions, though possibly not the correct angles. The steering needs to be changed to crossover with some fabrication, and the J-arm needs some TLC with the angle grinder/cutter also.
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Now the front axle is out I could pull down the leaf packs. Interestingly the passengers side pack had an extra leaf over the driver side. Must have been a dodgy repair from the dark ages.
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The centre bolts removed and the inner spring clamps undone to remove all but the 4 full load leafs in the pack. The PS pack took a little more time to remove the extra leaf.
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And reassembly using some new bolts with 4 full length leaves per pack. Despite the weight of the engine, I used 4 leafs/pack again on the front as I did on the rear as the shorter spring length will hopefully maintain a matched level of stiffness. Ride heights and ramp travel will verify this later.
The axle went back in and significantly the spring perches on the axle lined up nicely with the Landies springs. This makes life easy and fitting of the axle pretty quick. A quick check of ride heights brings the front to a level that is 2" over the rear, and a lift of 4" all up. This is a bit higher than what I was after reducing this is something to think about. The springs are very soft after jumping on them.
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Some better pics of the IIa's new stance.Initially I thought the back had come up by 2" and the front by 4", but it seems the guards are not the same front / back and my measurements are out. When the wheels are compared to the sills it looks like the ride height is level, though not with the top of the guards. Maybe I should trim the rear guards to match???
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and the spring over.
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The DS spring plate still needs the long U-bolt attached. The plate needs to be redrilled for this as the perch is not manufactures at 90 degrees to the axle housings, and so the holes are offset, especially in relation to the spring pack bolt. Again the spring plates have been swapped and its looking like the factory shocks will work with this setup. Again the angle of the shock will be at about 45 degrees giving extra travel but less effectiveness. The steering damper will bolt straight into the standard Hilux position, and the steering is still to be connected

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The hilux diffs were about $400 I think it was with 4.88 ratios. I've thought long and hard about replacing them again with wider diffs, which will also allow using an outboard coil setup and give it some extra stability, but will just leave it. I don't think I'd use the nissans, because its hard to get good CV's for them. They're no better than the toyota ones, but strong Toy ones are everywhere. I think the LC60 axles would be very good though. These also all come, as far as I know, in 4.11 gears which is good for 33-35's, the LC60 power steer will bolt straight up and parts are cheap (about $700 for axles complete). The trade off though is the diff pumpkins are a lot bigger and so to maintain the clearance you need to run bigger tyres. 29's on a Rover has the same clearance as 31's on a Patrol/LC, which is why 've stayed with Hilux diffs (very similar to Rover clearances)

Another option! People are getting into fitting Hilux diff centres to Rover axles. I'm pretty sure the Rover axles are comparibly wide, though rover runs less offset in the rims. Redrill the axle housing to suit the Toyota 3rd member and in it goes. These are a lot stronger than the rover units with Toyotas Hypoid setup. Jack McNamara will make lockers to suit Rover 24 spline axles also, or the axles need to be made from Toy 31 spline to rover 24 spline. The pinion does need to have a solid spacer though, not the standard crush tube, or that will still give.
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Cheers
Slunnie


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Discovery II "Storm" ~ Series IIa 6cyl ute ~ Series II V8 ute

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