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I am installing a set of front and rear mono leaf springs tomorrow.

Will this require a different steering pitman arm? Or is that only for the dropped axles?

Both steering arms and pitman may need to be modified to clear. With mono leafs or dropped axle you are moving everything up in the chassis. I used a dropped axle and had to tweak both to clear. Pitman arm must not be pointing up or down, must be level with the ground or you'll get bump steer.
Good luck

How would I modify the pitman arm?

After dropped axle was installed, we heated and bent the steering arm (top end that attaches to pitman) on that side so that the pitman arm was then still level with the ground. Make sure it will still move as needed and clear everything. My welder heated the arm with a torch, made the bend and then stuck it in a bucket of sand so it would cool slowly. Just make sure who does this knows what he is doing, wouldn't be good if the steering arm failed. We also replaced the tie rod, using one with modern ends and had to bend the arms a bit to clear the spings. Also make sure you are totally happy with the new springs before you start bending things. Best of luck

I am not installing a dropped axle yet, probably in a couple months. I am just installing the mono leafs

If using a Saginaw power steering w/ a splined pitman arm that has one spline skipped, just get a small 3 cornered file, file out the skip spline, then can mount in any position on shaft.

There is no power steering.

If you're going to use a drop axle, Nostalgia Sid's sells em with the modified pitman and steering arms and modern ended tie rods. Sid Drapal is a good guy too. Tell him your plan, what drop you got with the springs and he'll get you what you need.

@Bluemeanie I planned on going with exactly that.

But I still need to know if the pitman arm needs adjusting tomorrow with the mono leafs alone.

Call Sid. He can tell you for sure. ...you might be able to get away without it until you add the drop axle. I have a 4" axle with everything else modified to compliment it. I later ended up removing several leaves to get the height I was after. Nothing changed significantly enough to warrant further alterations. I figure I'm about 5.5-6" lower in front.

Yup..what JiMerit Boltr#43 said. I have a 1954 GMC 9300 with mono leafs. The pitman arm is on an uphill slope and I get a fair amount of bump steer, especially on bridge expansion joints. This winter I'm going to start bending stuff to resolve the issue.

canuck49, can you describe your bump steer on the expansion joints in laymen's terms.

Ok well, when you hit a joint with firm grip on the steering wheel the truck darts back and forth and depending on speed feels like you're really not in control. I've learned to hold the wheel loose and let it rock back and forth in my hand then the truck runs straight.

Why is my axle so low that it is touching the frame? I doubt this is how it is suppose to look.
http://imgur.com/fMfeFQH

Looks like someone removed all but the main leaf in the springs.

Dennis

If that is the original main spring, used by itself, is that safe?

Presumably, a properly designed/rated mono-spring would be safe?

Thats the mono leaf spring from BrothersTrucks as mentioned in the beginning of this thread.

Here are shocks that Brothers sells for a 3" drop.
Maybe for use with this drop-kit and standard springs?

It is interesting/odd that their mono-leaf springs are made for 4" or 5" drop, but they list no shocks?
Did you call them for advice on what shocks to use?

Didn't notice the rear was also a new mono leaf. It looks like it is bending the wrong direction to me. Is it installed right side up? I'm assuming there are no lowering blocks. Can't make that part out in the picture.

Dennis

I tried installing it the other way around but there is no way, the part wont fit right. There are no lowering blocks.

According to BrothersTrucks, I will need to add C-Notch's to the frame.

I have 1 1/2 inches in front to bump stop and 3 1/3 inches in the rear. This is with Patrick"s mono leafs on a 1954 Canadian GMC 9300.