Land cruiser steering box

I've been searching threads on what steering box to use as a upgrade on my d5n to power steering , seems the land cruiser is the go, but what series cruiser steering box is the best to use ? Any info muchly apreciated, I have a holden hz pump to use , ideas,?

What size D5N? When I did my F100 I used a 75 series cruiser and it was good until I went to 35inch tyres then the box didn't like the load. If it is a small dodge then the cruiser box might be okay but if it is a big one with 20 inch wheels the cruiser box may be a little under rated. Also on the subject of the pump you need to match the pressure of the pump to the pressure that the box had originally otherwise the system will be compromised.

Hey 600 thanks for the reply and merry Xmas, it's a 8500 Gvm 300 series d5n , so I can legally carry 5 ton roughly on the back, powered by a rebuild 318 40 thou over pistons, bigger valves, longer duration cam , air gap manifold with holley 600 and electronic after market dizzy,
I'm not too sure on the diameter of the wheels , I'm away on holidays at the moment but can check when I get home

Just talking to my dad he is a mechanic , and said that there is a pressure relief valve in eather the pump or the box depending on models , and can control the flow and pressure by ajusting it

I have been playing with landcruisers for a while. 60, 75 and 80 series boxes all mount directly to the side of the chassis rail, there are some differences in direction of rotation, shape of pitman arm etc. i can take piccies of any of the above and give you dimensions if you need them at some stage, cheers Pat

Hi Hemi, merry xmas to you. Its not so much over pressure, as you dad said you can adjust the over pressure valve to relieve earlier, but under pressure that causes problems. If you have less pressure than what the OEM supplied the box then it may not perform as it should.

Simple solution is to use the box and pump from the same model vehicle.

Mounting a pump isn't hard and open to a lot less problems than replacing the steering box with one from another make and model.

Used a box from a '75 series in my Inter Scout. Ended up running 35's with no problems. When I was looking for the box I was advised to find one out of a rusted out cruiser as opposed to one that had been in a smash, less chance of internal damage...kinda makes sense. Cheers, Paul.

Ah yes lower pressure would cause havoc , I see the logic in having same model pump and box due to all ready being set up pressure wise and I suppose there wouldn't need any hose mods needed to adapt hoses to suit the mix and match, thanks wreckerpat that could come in handy , not sure what box will be suitable for my truck yet as I will be carrying a ditch witch trencher on the back that weighs in at around 3 tons, maybe the f250 box might be a bit heavy and suit it better but what research I've done seems the F box needs a lot more modification to get it right. I'd rather over kill it then run something a bit lighter , truck is not registered at the moment but I spoke to the guy that is going to do the roadworthy and asked him if I put on mod power steering , would he pass it, and his reply was if it looks neat and structurally sound would pass it.

Maybe a box from like a Mazda/Ford T3500 truck.