The whole D60 knuckle on Jeep pitman arm issue

[thenag]

So with OEM full size knuckles on a xj/tj etc the stock pitman arm (and regular drop pitman arms) are not long enough to allow the steering full lock to lock turning.

I like my drop pitman arm, it matches my drop track bar bracket.

On my setup could I just re-locate the tie rod end on the drag link closer to the knuckle?



Thanks!

Nathan

 

[Gravy]

Yes.

With the effect of having less leverage on the steering arm.

or

get a longer (hole to hole) drop pitman arm. (superlift makes one).

Either way the right thing to do is add hydro assist and stop having issues turning with your lunchbox locker.

 

[Badger]

I think you want to find an arm from a FSJ. I want to say that's what I used. I believe it was an 1" longer hole to hole.

 

[Gravy]

I think you want to find an arm from a FSJ. I want to say that's what I used. I believe it was an 1" longer hole to hole.

True Story
His issue is that a FSJ arm is nearly flat. That being said the drop pitman arm from Superlift has the same part # list for the FSJ and FSB.

BJ's offroad sells them for like $65 bucks.

 

[I Lean]

How much drop do you have now? Do you have room for a longer center-to-center arm with the same drop, or will your diff (or anything else) get friendly with it on compression?

If you don't have room for a longer pitman, then yes--shorten the distance from the balljoint to the tie rod end at the steering arm.

 

[thenag]

How much drop do you have now? Do you have room for a longer center-to-center arm with the same drop, or will your diff (or anything else) get friendly with it on compression?

If you don't have room for a longer pitman, then yes--shorten the distance from the balljoint to the tie rod end at the steering arm.

I need to measure, it is a lot of drop. I think I should clear front diff etc even with the longer pitman arm.

Yes.

With the effect of having less leverage on the steering arm.

If both arms are shorter or longer would it have any effect on leverage? With a longer arm on the knuckle it would take less force for the tie rod to to push the knuckle, but with a longer pitman arm wouldn't it take more force from the sector shaft? I am not sure this is one of those things I can't wrap my head around, I should send the question to my engineer friend...

Either way the right thing to do is add hydro assist and stop having issues turning with your lunchbox locker.

This is the pre-work to the hydro assist. I can't figure out if a hydro ram will push at the same rate as the current tie rod (or if it matters), but this issue needs to be figured out anyway. Since I am going hydro assist I don't really care if my pitman arm looses force since most of it will be moved down to the axle.

Also as I have mentioned most of the time I can get the wheels turned with the lock-rite, but even with the wheels turned it still wants to go straight.

Don't worry there will be a "ok do I have everything figured out for hydro-assist?" thread coming soon...

Thanks!

Nathan

 

[I Lean]

A longer pitman arm OR a shorter knuckle-side arm will reduce the force available at the knuckle for steering. You will gain steering angle. (assuming you aren't getting to your steering stops now)

Hydraulic assist speed or force is 100% controlled by the valving in the steering box. The more pressure you put on the steering wheel, the more pressure is applied to the ram. You only run into issues if your ram is too large for the power steering pump to feed it when trying to steer quickly. (or if the orifice sizes are inadequate within the steering box or wherever)

 

[thenag]

Hydraulic assist speed or force is 100% controlled by the valving in the steering box. The more pressure you put on the steering wheel, the more pressure is applied to the ram. You only run into issues if your ram is too large for the power steering pump to feed it when trying to steer quickly. (or if the orifice sizes are inadequate within the steering box or wherever)

I get that about speed and force, but what about what about the throw of the ram? If the ram pushes the tie rod 2 inches and the pitman arm pushes the drag link 1 inch something is going to have issues...

(but this is getting into my future thread...)

nathan

 

[thenag]

A longer pitman arm OR a shorter knuckle-side arm will reduce the force available at the knuckle for steering. You will gain steering angle. (assuming you aren't getting to your steering stops now)

so a OEM style jeep pitman arm with a dana 30 compared to a FSB pitman arm with a D60, the steering box has to exert the same force (in theory)?

Nathan

 

[I Lean]

I get that about speed and force, but what about what about the throw of the ram? If the ram pushes the tie rod 2 inches and the pitman arm pushes the drag link 1 inch something is going to have issues...

(but this is getting into my future thread...)

nathan

Non-issue, since the fluid is controlled by the steering valve. If the ram "wants" to go slower than the steering box, you'll end up applying more steering wheel force, which will open the spool valve and send more fluid to the ram--and vice versa.

so a OEM style jeep pitman arm with a dana 30 compared to a FSB pitman arm with a D60, the steering box has to exert the same force (in theory)?

Nathan

If you're talking the same size tires in this theory, then yes.

 

[thenag]

Non-issue, since the fluid is controlled by the steering valve. If the ram "wants" to go slower than the steering box, you'll end up applying more steering wheel force, which will open the spool valve and send more fluid to the ram--and vice versa.
p

That makes sense and no sense at the same time... I figured since everyone wasn't tearing pitman arms off it wasn't an issue but I couldn't figure out why...

Thanks