In search of confirmation

[377]

Hello
I’m in the process of gathering parts for a project I’m going to start in the near future. I’m wanting to build a rig with a 100” wheelbase, so I thought I’d move both the front and rear axles each 4” . The question I have with moving the front axle forward. Moving the axle forward I won’t be able to use a steering box with a rear facing pitman arm. From posts I have went through it seems a 75 to 78 F150 4x4 steering box would work because it has a forward facing pitman arm? If this box will work are the mounting holes an issue when mounting the F150 box to the frame? I’d really appreciate your advice or experience doing this. Thank you for your help.

 

[ericwilkison]

Check out information on mounting a rockcrawler or 4x4x2 box. This is the f150 4x4 box with the worm gear from a f150 4x2 box installed so it turns the correct way. In your case you would not need to swap the internals because your moving the axle forward. But the information on mounting the box to the frame would apply.

http://www.wcb4x4.com/tech/diyrockcrawler.shtml

 

[377]

Thanks Eric,
I appreciate the link to West Coast Broncos. I’ve used some of their parts in the past. I’m not really sure what’s going on with their website or them. I called them a year or so ago and left a voice mail. I didn’t hear back from them, I hope for their sake they’re still in business. I totally forgot but Wild Horses makes a mount that looks like it does the same thing. I’ll be getting one of those. Thanks again!

 

[DirtDonk]

You may be thinking of BCB on that adapter/spacer/plate thingy. Unless a new product release snuck past me (wouldn't be the first time!) we have always maintained that bolting it to the frame slightly forward of where the adapters placed it was best.
This does mean notching the front body mount support on the frame, but that's minimal and the benefit is great.

But the primary reason for that is to place the box in a better spot, and ensure that the rear facing pitman arm of the 4x4x2 conversion will not hit anything else during suspension cycling.
With you moving your axle forward so much, it's hard to tell what you will need until you start mocking things up. LOTS of mocking up!

You may find that putting it right where the stock box mounts is best, what with the pitman arm roughly 10" or so farther forward than it would normally be with the converted box, there's going to be a lot of figuring and factoring and head-scratching before it's done.

With the big box there are considerations such as the physically larger size of the box, clearing the side tank of the radiator, clearing the core support (which you may not need depending on body modifications?), clearing the wheel well (again, unless you're removing lots of sheet metal already?), shaft alignment, draglink angle, clearance to spring tower (if applicable) and trackbar bracket. And etc...

Is this going to be a stock-ish design coil spring radius arm suspension? Or coilovers and such? Trackbar still, or 4-link, 3-link, or "other" perhaps?

I say get the box, clamp it where it looks good with the stock pitman arm, then start mocking up your suspension and drivetrain and steering linkage to make sure it's all going to play nice together. See if you'll need a custom pitman arm or not, and go from there.
All this before deciding exactly where to mount the box.

Paul

 

[377]

Paul
I wasn’t planning on using a 4x4x2 box because of it’s rearward facing pitman arm wouldn’t work with the axle being moved unless body mount and core support were modified. I thought if I could get an F150 4x4 box mounted in the same area as the stock bronco I wouldn’t have to change the body mount and core support. But with the F150’s forward facing pitman it would compensate for the front axle being moved. Because it would relocate the drag link into a position that would work with the front axle being moved. I saw your mount goes on the inside of the frame but couldn’t the mount be put on the outside of the frame? The front suspension will be a three link with a track bar. Here is the part I thought I could use to accomplish mounting an F150 bo. https://www.wildhorses4x4.com/produ...e_Box_Bracket_F150/bronco_Power_Steering_Kits
I’m I completely off base with my thinking?

 

[garberz]

377, that bracket is actually for the F100 box that mounts on the inside of the frame. You’d be much better off with the BCB’s steering box frame plate. It has both bolt patterns, stock Bronco and 78’-79’ F-1504x4 box. You may need to move the box back towards the firewall if you’re only moving the axle 4” forward. This plate can go where ever you need it. Since you’re 3 linking it, you’ll have a bit of fabbin’ To do.

https://bcbroncos.com/shop/steering/steering-linkage/48-20011-ps-box-frame-reinforcement-kit-for-early-bronco/

Mark

 

[377]

Mark
Thanks for the link to the BCB part I wasn’t even aware they made anything like it until Paul mentioned it. The WH part kind of confused me because it’s labeled as an F150 mount but when I saw the instructions it said F100. Thanks again for the help with my questions, you guys on here always lead me in the right direction.

 

[DirtDonk]

Yep, understood what you were trying. Just saying that we don't offer a plate because we move the box forward into the body mount. But in your case with the 4x4 box it would likely need to be as far back as possible. Which means it will hit the trackbar bracket unless it was removed (which is why I asked about the suspension) or the wheel well.

You'll be better off than someone that's just mounted a 4x4 box to a stock Bronco, which has been done before. It's got the draglink pulled pretty far forward, but you'd be helping that by the 4" forward move.

Just pointing out that there is going to be more mocking up necessary even though you'll be using it in 4x4 configuration.
Which I still think will be needed. I just wasn't clear that using the stock full-size box would still need some fiddling.

Will you be changing your cross-member location by any chance?

Paul

 

[DirtDonk]

F100 and F150 were both half-tons and shared most of the same architecture, with the 150 simply having a higher load capacity until the F100 was finally dropped.
The inside-the-frame steering box is for the 2wd version of either truck and was a very common box to find in the junkyards, inexpensive and very strong.

But yeah, mounting brackets not the same as what you need.

Paul

 

[377]

Ok now I understand where you’re coming from Paul. One thing I want to ask to be sure I’m understanding you guys correctly. The F150 box needs to be moved back because with its forward facing pitman arm it will be to far forward even with moving the front axle? Because if that’s the case I will have to think about moving the front cross member forward in order to use an inside the frame track bar mount. I had planned on moving the rear cross member back two inches. Do you have any suggestions on how far to move the front forward? Because in a lot of the posts I’ve read one guys says he moved this or that but in the same thread another guy will say he didn’t move anything. So needless to say I’m kinda confused. Thanks again

 

[DirtDonk]

Shouldn't be any confusion. It's just yet another case of "your results may vary" and that's it. Our results often vary VERY!

I'm not giving any specific info on moving the box either way. I'm simply saying I have no way to know what you're going to need, and the need to mock things up is paramount so you don't run into interference with something halfway through the project.
I literally don't know where you'll put the box. Just saying that there are a LOT of things that might possibly be in the way no matter which way you go.
Since I don't know what other mods you're doing, I don't know what else can be modified, moved, tweaked or removed completely.

If you put it in the stock location it might be perfect.
Or not...

Paul

 

[Scoop]

I got my wheel base to about 103. I was trying for 104. I didn't want to mess with the steering so I moved the front 1 1/2" which was as far as I could get without interfering. I extended the frame in the rear 8 1/2" and then got another 1 1/2" using Zero Rates. I didn't not stretch the body. Sure another 2 1/2' in the front will get you a little better approach angle but it's a lot of work for minimal gain. Just my thoughts.

 

[stevew]

Hey Paul , another project or new ideas on the current one ?
So years ago I had a stock (no lift ) Bronco in the shop that had a F150 4x4 box hacked in . Forward facing pitman like you're talking about . They had mounted the box as far BACK as possible . I don't remember any mods done to the track bar bracket but the wheel tub was really hacked . Seems the drag link was at an odd angle but the thing drove ! My thoughts are just mock it up until you get it right & not hope for a "quick fix " ready made bracket .
Anyway don't be a stranger !

 

[DirtDonk]

Yeah the draglinks can be at some awkward angles doing it with the stock 4x4 box.
The Cross, of Cross Enterprises (can't remember his first name at the moment and, what with the Super Bowl looming, all I can think of is Randy!) did one that way on his nice Green Bronco to get on the road before he had the chance to swap the guts to reverse the steering and drove it to one of the Bronco anniversaries (20th, or 25th maybe?) back when we used to do those.
It drove passably well, but was never going to really dial-in with that odd angle. But maybe because the box was quicker than an original EB box, maybe it covered some of the problem.
In fact, I never heard if he actually swapped the guts or just left it!

You can get the box as far back as the trackbar bracket, but that's not very much farther back than stock if I remember. Less than an inch probably.
But even at the stock location, the rear bolts are up against the crossmember. In some cases with enough clearance for a wrench, in others they are fully jammed up against it. Variations from the factory. So when you move it back even 1/4" you're into modifying the crossmember, the mounting points, or both.
Moving forward (if needed) has it's own set of issues as well.

Ya just can't win I tell ya!

Paul

 

[sprdv1]

Yeah.

Ya just can't win I tell ya!

lol, never fails

 

[sprdv1]

Hello
I’m in the process of gathering parts for a project I’m going to start in the near future. I’m wanting to build a rig with a 100” wheelbase, so I thought I’d move both the front and rear axles each 4” . The question I have with moving the front axle forward. Moving the axle forward I won’t be able to use a steering box with a rear facing pitman arm. From posts I have went through it seems a 75 to 78 F150 4x4 steering box would work because it has a forward facing pitman arm? If this box will work are the mounting holes an issue when mounting the F150 box to the frame? I’d really appreciate your advice or experience doing this. Thank you for your help.

Was about to say, take it to someone who's done it before, but doubt too many options out your way?

Good luck.. Have a good plan, all the parts and get right n there if you do it yourself

 

[377]

Thanks for advice guys. I knew going into this there wasn’t there wasn’t going to be a bolt on option. That being said that’s kinda why I like doing stuff like this. I couldn’t agree more with mocking up things. That part isn’t my first rodeo but, deciding to try put an F150 box on stretched wheelbase is definitely my first rodeo do that. But I’ll do exactly what Montana’s Cowboys do at every rodeo in Montana they get bucked off and the next weekend their in next town down getting right back on. Thanks again for the advice. Steve it was great talking to you, you solved a bunch of problems that I saw coming down the road with this project. Have a good night and take care guys.