steer box tapping for hydro

[UZJ40]

need to tap my steer box for hydro assit.

its an 80 series box, anyone got a pic of where i put the holes exactly.

any tips?

[MART]

All the guys I know of or have seen there trucks , Glen dobbin has drill and tapped the holes , He's at smithfield , dobbin engineering , Cheers Paul.

[tuf045]

try this thread http://www.outerlimits4x4.com/viewtopic ... t+steering

[professor]

need to tap my steer box for hydro assit.

its an 80 series box, anyone got a pic of where i put the holes exactly.

any tips?

I will grab a few pics when my rig is back.

the ports are ontop of the 80 ser box and are nearly side by side one in the top plate and the other in the port line to the front of the box.

if you pull it apart it is easy to see the two chambers that you need to tap into there is a ram inside the box that has a gear on the side that links the pitman arm basicly an A port and a B port to push the ram back and forth.
Be sure it is totaly apart and totaly cleaned beforeand after drilling and tapping.

a few things to remember

you will need more pump speed as the oil volume with hydro assist is doubled meaning it has twice the power of steer but half the speed of steer.

one way of getting around this is to as stated before is to speed the pump up. in my hilux i had alot of trouble getting the steer speed back to normal the first thing i tryed was the pump mod of the pressure relef beef up, i drilled the restrictor and doubled the spring pressure but i found this procedure didnt help allot so the next thing was to actuly speed the pump up. i did this by putting a smaller pully onto the pump, ended up around 60% faster in pump speed.
this helped but still didn't bring the steer speed back to normal the simptoms were good steering till the steering wheel had to move quick (ie missing a rock on a fire trail)when you move the steering wheel quickly the wheel becomes very heavy,better with the pump mods but still present.another mod that i tryed was to close circut the pump and force feed the return back to the pump i still have a tank but basicly the fluid goes straight back into the pump.

I had to change my driving style dramaticly I had to slow up in the hard stuff and take my time (limited by how fast the steering reacts)

having said all of this we have been trialing a cluster of mods and have had good sucess somuch so i was able to drive my old style of throughing the rig around and not thinking about any steering problem.

we havent tested all aspects of the falure situations yet so these mods will only be good for offroad use only for the time being.

the mods are simple but they do require a few new hoses and a bit of time to setup and there are a few dollars involved but well worth the good steering.


give me a call if you want more info on the mods

Chad 0418441064

[MUD000]

I've got it on mine
Cheezy had problems too turned one way perfect but lock up the other way at low speeds ie parking roundabouts etc Thought it was the pump but its not it was a flow problem not pressure so I got told
Had Toyota look at it in Albury & perfect now no differance in speed reaction turn as fast as you want with no hesitation & no lock up
No dfferance between normal & hydo (possibly quicker now if anything )
Cheers Dan