High Boy power-steering
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From: Cascade, ID
High Boy power-steering
I just got my hands on a '71 F250 4x, it appears to be on a later chassis. The wheel-base is about 2 inches too long.
So, I thought I would look here for the answer to my question. What is the best steering setup to use on the leaf-sprung front end. I have a F100 4x that I did a cross-over conversion on w a '79 F150 box. That thing drives better than most of the new trucks I have driven. I would like to do the same to this truck. Can I use a 2x power box? I haven't done much research on the leaf-sprung trucks.
So, I thought I would look here for the answer to my question. What is the best steering setup to use on the leaf-sprung front end. I have a F100 4x that I did a cross-over conversion on w a '79 F150 box. That thing drives better than most of the new trucks I have driven. I would like to do the same to this truck. Can I use a 2x power box? I haven't done much research on the leaf-sprung trucks.
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Post Fiend
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You may also do a crossover conversion on the leaf sprung truck. The 4wd can be used, and looks better than that long crazy 2wd box.
Couple things to lok for.
1. Not having enough arch in the leaf spring to clear the pitman arm while making right turns.
Fix: find a pitman arm that is flat and has no drop, Or use a rod end instead of the TRE, or lift the truck greater than the stock 73-77.5 spring.
2. Fitting the later 4x4 box requires some modification to the 73-77.5 crossmember.
Fix: Creative welding and some fabrication. Not too difficult.
This is probably the best modification that can be done to these early trucks. The steering design then was poor at best. Amazing what a good x-over conversion can do.
Couple things to lok for.
1. Not having enough arch in the leaf spring to clear the pitman arm while making right turns.
Fix: find a pitman arm that is flat and has no drop, Or use a rod end instead of the TRE, or lift the truck greater than the stock 73-77.5 spring.
2. Fitting the later 4x4 box requires some modification to the 73-77.5 crossmember.
Fix: Creative welding and some fabrication. Not too difficult.
This is probably the best modification that can be done to these early trucks. The steering design then was poor at best. Amazing what a good x-over conversion can do.
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From: Cascade, ID
So, what I am visualizing after reading the article is to use a 2x power box (because I have one) and covert to cross over (assuming the top of the pass. knuckle is flat). Though it is nice to know that I could keep it with the Chevy/Dodge style link with the same box and pitman. I assume I can use the 2x pitman then?
Post Fiend
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Scott:
I am not a big fan of the 2wd box. The long sctor shaft makes it a bit weak when used with large tires. It was also mounted right against the column and has a funky angle built into it, and looks a little funny. Most guys that use this box have to really butcher the frame to get this size box in there.
Just about any box will do. I have seen plenty of saginaw boxes in these trucks, so really whatever you are comfortable with will work.
The biggest thing you have to look out for, is the clearance of the pitman arm and the driverside leaf spring. This is a real limiting factor with trucks that are not lifted. If the truck is lifted, then you should have very lfew problems, and clearance here will not be an issue.
Also, if you wish to not machine the pass side knuckle to accept a new steering arm, and the truck is not too tall, an inverted "T" steering design works well too. Not as well as the full crossover, but a reasonable alternative.
I am not a big fan of the 2wd box. The long sctor shaft makes it a bit weak when used with large tires. It was also mounted right against the column and has a funky angle built into it, and looks a little funny. Most guys that use this box have to really butcher the frame to get this size box in there.
Just about any box will do. I have seen plenty of saginaw boxes in these trucks, so really whatever you are comfortable with will work.
The biggest thing you have to look out for, is the clearance of the pitman arm and the driverside leaf spring. This is a real limiting factor with trucks that are not lifted. If the truck is lifted, then you should have very lfew problems, and clearance here will not be an issue.
Also, if you wish to not machine the pass side knuckle to accept a new steering arm, and the truck is not too tall, an inverted "T" steering design works well too. Not as well as the full crossover, but a reasonable alternative.
Post Fiend
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From: Kasson, Minnesota
I did the conversion that the article talks about that Dennis posted. From what I have read and researched, the modification I chose using a 78-79 F250 4x4 steering box definately was the easiest for me. By using that conversion, you are able to use the stock drag link. You just have the exact same setup like the 78-79 F250 4x4s.
Post Fiend
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That article refers to a power steering conversion only, and does not refer to the
x-over conversion. If you will notice he mentions the limited right turning radius. This is the biggest problem with the push / pull style steering on 4 wheel drive units. That drag link is too short and limits the turning radius during suspension cycles. It can limit it so much that it will all together eliminate the ability to turn at all when the driver side is at full extension.
All boxes require some modification to fit, the saginaw box requires the least amount since it mounts to the outside of the frame.
I prefer the 4wd box just because it is compact and has a stronger sector shaft.
x-over conversion. If you will notice he mentions the limited right turning radius. This is the biggest problem with the push / pull style steering on 4 wheel drive units. That drag link is too short and limits the turning radius during suspension cycles. It can limit it so much that it will all together eliminate the ability to turn at all when the driver side is at full extension.
All boxes require some modification to fit, the saginaw box requires the least amount since it mounts to the outside of the frame.
I prefer the 4wd box just because it is compact and has a stronger sector shaft.
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From: Cascade, ID
yes it may be long and weaker, but I know where three 2x power boxes are, one of them is parked in my driveway.
The swap looked very doable, the only draw back would be the drag-link.
It did not look to me that the closed knuckle Dana 44 knuckle had enough material on top of it to bolt an arm to it that would stay there. The funky closed knuckle joints on these don't look very stout.
I was trying to decide if a guy could fabricate an arm on the pass side knuckle that bolted to both the upper bearing/joint retainer thing and also went down the inner side and bolted to the face where the joint seal plate bolted to. It would be stronger because it would spread the load out on a larger area and on two planes. I think it could be done, It would just take some time I spose. Probably use 1/2" plate for the top and 1/4" down the side with some sort of reinforcing web between them.
does anybody make an arm for the closed knuckle?[img]file:///C:/DOCUME%7E1/Owner/LOCALS%7E1/Temp/moz-screenshot-7.jpg[/img][img]file:///C:/DOCUME%7E1/Owner/LOCALS%7E1/Temp/moz-screenshot-6.jpg[/img]
The swap looked very doable, the only draw back would be the drag-link.
It did not look to me that the closed knuckle Dana 44 knuckle had enough material on top of it to bolt an arm to it that would stay there. The funky closed knuckle joints on these don't look very stout.
I was trying to decide if a guy could fabricate an arm on the pass side knuckle that bolted to both the upper bearing/joint retainer thing and also went down the inner side and bolted to the face where the joint seal plate bolted to. It would be stronger because it would spread the load out on a larger area and on two planes. I think it could be done, It would just take some time I spose. Probably use 1/2" plate for the top and 1/4" down the side with some sort of reinforcing web between them.
does anybody make an arm for the closed knuckle?[img]file:///C:/DOCUME%7E1/Owner/LOCALS%7E1/Temp/moz-screenshot-7.jpg[/img][img]file:///C:/DOCUME%7E1/Owner/LOCALS%7E1/Temp/moz-screenshot-6.jpg[/img]
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Post Fiend
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As we were discussing this, I realized that you may have a closed knuckle unit. This is why I made the comment about the "inverted T" system. You would attach to the tie rod instead of the knuckle, similar to the f-150s and broncos with solid axles. Works better than the short push pull system, and is a lot less time consuming than trying to fab up a bracket.
Post Fiend
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Yeah man, the steering system does not know what it is connected to, it just has to be right.
I have converted several D44 equiped F250's to this style steering. Heak if you can weld alittle, you can make a complete tie rod with brand new tie rod ends and a simple mount welded to the pass side to accomodate a 3/4" rod end that attaches to the drag link.
Pretty easy really.
I have converted several D44 equiped F250's to this style steering. Heak if you can weld alittle, you can make a complete tie rod with brand new tie rod ends and a simple mount welded to the pass side to accomodate a 3/4" rod end that attaches to the drag link.
Pretty easy really.
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Elder User
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From: Cascade, ID
That is something to think about, I may go the drag link route for now since I don't currently have a job and my house payment is due in another 2 weeks. Hopefully my student loan $$$$$ comes soon.