Hilux / Surf Modifications & Tech

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SupraLux
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Hilux / Surf Modifications & Tech

Postby SupraLux » Wed Nov 23, 2005 12:53 pm

Ok, been meaning to do this for a while now - DB's Nissan one is brilliant, I'll try and make this half as good for all the Toy Lux and Smurf drivers out there. A lot of the stuff in here gets asked all the time so hopefully this can be a one stop shop to answer most of the questions.

Please don't reply to this thread - That way it can stay short and sweet and complete - without going wildly off topic or getting doubled up. IF you have something to include, PM it to me and I'll keep it updated.

Body Lift
http://www.offroadexpress.co.nz/Forums/viewtopic.php?t=1306


Budget Cross Over Steering
http://www.offroadexpress.co.nz/Forums/viewtopic.php?t=1432


Falcon Spring Conversion
http://www.offroadexpress.co.nz/Forums/viewtopic.php?p=3069#p3069
and a snippet from the conversion I did on Conans truck:
http://www.offroadexpress.co.nz/Forums/viewtopic.php?t=1147&start=25
A few notes on the 'coon-version:
*You need to do a u-bolt flip as the square ubolts won't fit over the 65mm wide springs (Hilux springs are only 60mm wide).

*You then need to remount the shocks as the bottom shock mount was on the old u-bolt plate

*Bellamy and East in Christchurch will redrill the spring packs for around $75, or I can do it for you for the same price (Primary and secondary leaf only, just turn the rest around the other way). Hardened spring steel is nasty to drill.

*It would pay to replace probably the 2nd leaf with a new one - about $65 each to help the resting posture of the vehicle - these springs sit very flat at rest, even tho they flex waaaay better than anything else I've seen on these (excepting coils, of course).


LSD (Limited Slip Diff) Tightening info
http://www.offroadexpress.co.nz/Forums/viewtopic.php?p=19414

Shock Absorbers
The factory shocks are hopelessly under-rated for anything more than standard suspension and on-road driving. After 20 years under your truck, they will also be totally knackered so replacing them is a good idea.

The shocks should be replaced with long travel gas charged ones for any sort of offroad use, or Rancho adjustables are a good choice (depending who you ask - some people have had problems with reliability from Rancho although I've never had one fail on me). I'll post the Rancho part numbers for their longer travel ones when I remember or when someone pesters me :)

Rancho 5000 series shocks are non-adjustable, and the valving is too hard for a light vehicle like a Surf or Hilux making the ride very harsh - I'd recommend them in Cruisers and Poo-trolls, but not smaller vehicles.

GQ Patrol rear shocks have the same mounting as Hilux rear shocks, but are about 50mm longer in the extended position - this is a good choice for long travel in the back of leaf spring Hiluxes and surfs although I have not fitted them to an unmodified rear so can't say if you need to extend bump stops to stop them trashing under compression.

60-series front shocks have the same mountings as coil sprung rear surfs with about 30mm more extended travel, so are a good choice for the back end of surfs with 50mm lifted coils.

A trick for more travel in the front of IFS trucks is to put both the top pin bushes under the mount instead of one either side, and get a third bush (use one of the older ones if you are fitting new shocks) to go on top - the pins are long enough to do this, just don't fully wind down the nylock nut or you'll crush the bushes too much with three of them in there.

Always be careful when using longer shocks that the suspension can fully travel up without the shock fully compressing - or the shock will take the 'shock' when the suspension is compressed - a very quick way to turn it into a useless but expensive metal tube.


Suspension Lift - Rear Leaf Springs
There hasn't been a full post on this that I could find, so here is my take on it:
Leaf-spring models have a variety of options available - Just about every 4WD shop sells springs for these with varying qualities and prices. Do your homework and ring around before buying them (don't forget to ring me as well :P ) and ask on here for what people have used and how well they performed.

This is just a brief overview and I won't go into safety issues - if you don't have the tools, or the skills them don't do this - Hiluxes are light at around 1.7 tonnes, but the human body doesn't take kindly to having that kind of weight on top of it... I take no responsibility for your abilities (or inabilities) - use this info at your own risk - if in doubt there are plenty of skilled people around who can do this work for you.

The rear springs are easy enough to change, but the U-bolt nuts (most are 19mm, some are 21) are probably going to be very tight to undo normally - use a good 1/2" drive socket set - a 3/8" ratchet will probably snap getting them undone - also soak them all with CRC or WD40 a day before you need to undo them, and wire brush the threads to help you on your way.

Factory bushes, shackles and pins will probably need to be replaced at this point as well, as they are going to be pretty worn after 20-odd years of service. A good idea is to replace them with greasable ones, or if you're going for extra lift, greasable extended ones (I manufacture these as they can be hard to find). Rubber bushes have better flexibility than urethane ones but if you're lifting the truck up then urethane will help (a little) with truck stability on the road.

Loosen the nuts on the shackles before you even jack the vehicle up - the reason for this will become evident if you don't - they swing around when you try to undo them and its a pain. They are normally 19mm and will probably be quite tight, like everything else.

To remove the pins, undo the main 19mm nut on the inside (use a spanner on the drivers side, as the fuel tank gets in the way of anything else), then the two 12mm head bolts on the outside (replace these - they will probably shear off when you refit them, if they don't shear while you are undoing them), then figure out a cunning way of getting the pin out - as it could be rusted in place. On the passenger side you can give it a few taps on the inside with a hammer (keep the nut half on so you don't deform the thread unless you're definitely replacing it) to knock it out - on the drivers side use a small sharp prybar or similar and try to knock it between the pin and the spring mount to pry it out, taking care not to bend the mount.

To get the shackles apart, slip the plate off one side the removable plate is the one under the nuts) and then use a drift and a hammer to force the other plate with the pins attached as it could be jammed tight into the old rubber bushes.

At this point, there should be nothing holding the springs into the truck any more, and you can remove them carefully (don't catch and damage the handbrake cable while pulling them out), and fit the new ones in place. I would strongly recommend fitting new bushes and greasable hardware as well, and to be safe you are recommended to replace U-bolts at the same time (high tensile bolts etc should only ever be tightened to their recommended torque values once, as they stretch during that tightening process). The proper torque values should be available from Toyota - and I'll add them in here if/when I can find them. If in doubt do the pins and shackles up tight, and the u-bolts up bloody tight :) Also check the u-bolts again after the first drive, and again after the first week of driving.


Suspension Lift - Front Leaf Springs
This is mostly the same as the rear, but you will probably need to use a ratchet tie down or hand winch or something similar to get the axle back onto the springs as the torque rod can force it away from where the spring pins drop into the axle seat. Also take note of which way around the passenger side axle plate went around, one way around makes it stick down more than it needs to.


Suspension Lift - Rear Coil Springs
This is a simple mod if you have the right tools, and doo-able but a pain if you have half of them. I'm reciting this from memory, so let me know if I miss anything :)

Jack the truck up and use big axle stands under the chassis rails just forward of the bottom rear radius arm mounts, so the axle is hanging at full droop with the wheels off. Undo the bottom shock mounts (17mm) and slip them off - this will allow the axle to drop a little more. Then it helps to undo the Panhard rod from the axle (22mm?) and slip that off - might need a prybar. I also take the sway bar off both sides to help allow droop for getting the springs out and in.

You should just about be able to pop the old springs out with a little gentle persuasion from a prybar, or use coil spring compressors if you have them. Then use the compressors again on your new springs (I have also successfully used two ratchet tie-downs to compress the springs enough to get them in) and fit them in, making sure the rubber seats are still in place, the spring is the right way up, and the end of the coil is seated correctly in its groove.

The drivers side is harder to fit in due to the top arm stopping on the fuel tank and the brake line stretching - undo the brake line from the axle (12mm) and gently bend it up to alleviate pressure on the flexible hose.

Then reverse all the undo process (The panhard rod is easier to re-attach with weight on the vehicle) - have someone pushing the side of the truck to help line it up as well.


Suspension Lift - Front Torsion Bars
Generally this is done to try and match the front to a 50mm lifted rear and needs to be done with care and attention as done wrong it can lead to serious handling problems.

You can normally get away with approximately 30mm of lift in the front without causing trouble, but never lift it fully up or you will have no 'droop', which means when you go around a corner or over a bump the wheels can't travel out, so the wheel lifts instead...

First, measure from the rim to the guard to get a baseline measurement. Then jack the truck fully up from the crossmember that runs under the engine and measure the full-droop. Most likely there will be about 50-60mm difference. I always leave at least 30mm of out travel when doing this lift, and it often equates to around 20-30 1/4-turns of each side adjust bolt (I use 1/4 turns because thats the easiest amount to turn it when you are under the truck).

Start by checking if the adjuster bolt (22mm big bolt just inside the chassis rail and at the end of the torsion bar, points straight down) has a lock-nut on top - if it does, you need a triple jointed arm to get in and crack it loose - don't forget to tighten it when you are done.

Turn each bolt (NOTE: ONLY turn the bolts with the wheels fully drooped - the extra stress of the truck weight can cause the threads to deform) about 10 1/4-turns then lower the jack and re-measure the rim-to-guard. When you are happy that each side is the same and where you want it re-tighten the lock-nuts (if fitted) and you're done.
Last edited by SupraLux on Thu Jun 08, 2006 10:15 am, edited 1 time in total.

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SupraLux
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Postby SupraLux » Fri Nov 25, 2005 11:44 am

Hilux Surf Descriptions and Info

First of all a little tech. The LN series of Hiluxes and Surfs refers to the L-series engines - ie: an LN60 is a L-series diesel powered Surf, wheras the YN60 refers to the Y-series petrol powered model of the same thing. The other common one you might see around is the RN - meaning it has the R-series petrol - not common in NZ. KZN refers to the later 3.0 litre turbo diesel motor.

60-series Surf
Image
This is a truck I fitted falcon springs to - they don't flex like this outta the box, but they can be made to for very little money.

The 60 was produced 1984-1985, and was the only Surf to come from the factory with a solid front axle.

Typically they had a 2.4 litre normally aspirated Diesel (2L), although some were fitted with the 2 litre petrol engine (3Y). This is typical in NZ, although in the US they had mainly R-series engines - the most common being the 22R, a 2.4 petrol.

The beam axle and factory power steer and 5-speed makes this about the most popular and best choice for a base to build a capable offroader. They are reasonably common and cheap/easy to work on.

61-series Surf
Image
This is Matts one (Matt4U) - before he started tinkering...

This model appeared in late 1985 and ran through till 1989. In their infinite wisdom Toyota removed the front axle and put in IFS, and if that wasn't enough they bolted a CT-20 hairdryer to the engine so that it could blow heads randomly and regularly. No other changes were made, other than to change the old chocolate brown interior common in most 60's to the gunmetal grey (inside and out) that most 61's had.

They are vitually indistinguishable from the 60 unless you look under the front and see the suspension setup.

The engine was most commonly a 2.4 turbo diesel (2L-T) although there was some crossover and some 60's had this engine too, and some 61's had the 2L.

This truck is as common as Latte's in Merivale (Ponsonby if you're from up north :P) and they can be picked up for a song. Its possible to retrofit a solid axle into them, but the cost is normally a killer for that project - if you're going to SAS a surf, the 130-series is probably a more sensible option these days.

130-series Surf
Image
This is a bog-standard 130-series. It has since had about 100mm of lift, with a few other mods on the way... its driving around Christchurch somewhere

These trucks were the first major overhaul that Toyota made on the Surf since they designed them. They added a couple of doors (although there are 3-door models around, but they're not too common) and gave them a full cosmetic makeover. The series ran from around 1989 'till around 1995 (someone correct me here) and had 3 main engines: The 3Y-E which was an ECU controlled 2 litre petrol based on the old 3Y, the 2L-TE which, similarly, was an ECU controlled 2.4 Turbo Diesel based on the 2L-T, and in about 1993 they changed to being mostly powered by the far better engineered, far more powerful and all-round superior KZ series (1KZ-TE) 3.0 litre turbo-diesel engine.

They are IFS, but there are many SAS'd ones out there, and being nice and modern inside, and cheap to buy now - they are a good candidate for the swap.

185-series Surf
Image
A pic I pinched from the 'net - I don't know anyone with enough money to buy and mod one of these :)

This is the new generation of fancy-pants Surfs. If you can afford one you probably don't want to dent it so theres not too many playing in the bush. If someone knows more about them than I do then feel free to PM me the details and I'll post them.

They have airbags, they have ABS, they have all sorts of things you don't want when you're bouncing around offroad so getting them trail-ready would be a mission.

Standard Vehicle how big can I go?

I will write this pertaining to the 1st, 2nd generation solid axle trucks because that is all i have owned or know about.

33/12.50's are as big as you can go without cutting and still have it work offroad. I am sure some guy has squeezed in a 35 but the rubbing would be out of hand on anything more than a painted white line.

Now I did not say no alterations, you will need to pull off those plastic front bumper caps, pull out that plastic inner fender crap, and take the BFH (THE BIG FRIENDLY HAMMER) to the pinch welds on the firewall. If you do not want to do these steps you can get a 32/11.50 in there without any alterations except trimming back the front bumper plastic this info may not pertain to all brands of tire since actual tire size can very and it will also very based on wheels used.

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