power steering BOX questions (1 Viewer)

[subzali]

I know power steering of all different amalgamations has been covered to death, but I'm not sure anyone has asked/answered this question. If so let me know and I'll search some more.

WHY is Saginaw etc. "stronger" than minitruck etc.? Minitruck p/s uses a Saginaw PUMP, so is the BOX the point at which it lacks in overcoming resistance to turning? Same with FJ60 p/s, is can use a Saginaw PUMP, so is there a reason why the Saginaw BOX is better/stronger/better able to overcome resistance (assuming the same PUMP) than the FJ60 box?

Or does it have to do with linkages? The minitruck uses all the old linkages, so there are smaller diameter rods, plus the center arm may not be up for heavy duty...

I guess I'm asking, since the Saginaw and FJ60 boxes both mount to the frame and go straight across to the wheels, is there any physical difference in the box itself that would make one better than the other for turning big tires or not being overpowered? Perhaps the gear/turn ratio inside the box?

 

[Downey]

I did not engineer any of those boxes (nor did probably anyone else on this forum) so I doubt you are going to get exact math from anyone. You are correct that many do not perfer the mini truck steering merely because it still leaves you using too many of the old middle-men, and each one of those guys leaves you with some degree of slop. I personally would prefer the Saginaw to FJ60 merely to avoid the need to modify the upper shock tower. This is probably a non-issue to others on this forum though.

 

[mudnyreye]

I think that the saginaw system is stronger because of the placement of the mounting. With the saginaw, you are utilizing the strength of the front crossmember to help transfer any side to side force (or shear) The mini truck conversion or FJ-60 conversion can flex inward or outward with the flex of the frame 9Putting excess stress on frame and mount. I don't think it is a problem with 33's and mild wheeling, but I have seen trucks running 36+ tires break the mount and frame. Saginaw for big Knarly junk!

 

[65swb45]

Having seen the ears of a stock center arm RIPPED out of the frame on a mini conversion, I would not recommend one to anyone I cared about. The gentleman who handed me the broken center arm housing told me it was the SECOND ONE!

And FWIW, I will not install one in my shop. Not even for a street rig. As colangut has noted, rigs get sold, and the new owners may not understand the limitations of a mini conversion.

WURD.

 

[inkpot]

Howdy! It seems like the Saginaw is more over-built that any of the Toyota systems. They seem to be able to handle bigger tires with less problems. No science here, just 30 years of casual observations. John

 

[Mike Shull]

I belive in the early 80's Toyota's power steering was advertized as "Power Assist" ....maybe the valving in the Saginaw box is larger placing more hydraulic pressure to the "mini men"....or lack of arms swinging into each other.....I'm not sure but have run both set ups on an FJ-40 and must say that with the right set up Saginaw steering can work well both on road and off...but with less effort it may seem that the factory 60 steering handles better on road....at least for me...with that said..I love my Saginaw set up.