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Discussion Starter · #1 ·
So I have been building an f100 (74') and got some axles dana60/14bolt. I need a motor, its got a gt390 in it but it smokes bad. I figured id go to a diesel but I just installed my 5.13 gears in it!! I kinda wanted to stay with a bulletproof 4 speed behind the truck but with my calculations at 2000 rpm I will only have about 45 mph! My question is how strong are the dodge nv4500 trannies? I dont want to worry about the trans and I can deal with about 55 mph because the most I will do is tow with it if I am not wheeling it.
 

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You didn't say what tire size (OD), however with your numbers, 5.13, 1:1 4th, and 45mph @ 2000rpms = 39" tires :eek:

So, assuming you did do the Dodge NV4500 (or any NV4500), you would get a .73:1 overdrive in 5th

At 2000rpms you would still only be doing 62mph with your 5.13 R&P. Is that workable for your build? With a "redline" of say 2600rpms for the 4BT, your top speed (think passing) would be ~80mph, thats workable IMO.

However do you really plan to run 39" tires?
 

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Discussion Starter · #3 ·
its got 36's now I will probly end up on 42's. WHen I was towing I wouldnt want to drive on those tires though, so id probly have to sets. 60 mph is plenty for this truck. Its more of a wheeler, but if I can drive it to places that would be sweet!!
 

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Discussion Starter · #4 ·
heres the rig back when i had lift blocks and a chrome diff covered dana 44! :lol: now it got a 14 bolt.
that was when i was mocking up some pinion angle. dana 60
. now all i need is a nice 4bt or 6bt in here! ill go talk to the guy friday and see whats going to happen
 

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Discussion Starter · #5 · (Edited)
dont mind the ******* jack stands i fixed those, and I tied the frame horns together, tied the shackla hangars into the cross support and I am also going to add a piece of angle iron under the cross suport to tie into the shackle bolt
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stick welder :hillbilly:
 

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FWIW, my dodge would do 62mph at 2k RPM in 5th with the stock tires. Do a set of governor springs, and you won't worry about not enough RPM's on the highway in that truck.
 

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Discussion Starter · #7 ·
With what gears though? I think im just gonna try and find an nv4500 and run that, should be fine.
 

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I take it that's an 86-91 60 front? Why did you put the shackles in the front?

I would recommend the ZF 5 speed for ease of mating a Ford t-case, but you can put a Ford 205 to a dodge NV4500 with a custom mainshaft (preferred and cheapest route) or buy an AA kit.
 

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Discussion Starter · #10 ·
Yeah 6011 is what I used mainly. It looks alright but will hold up just fine. Yes it is a later d60. I will never use one of these again because of the perch width. I should have gone links but ill just run it like this for a while. I used front shackle because I wanted to run leaf springs that I had and the way the leafs I had mounted up (backwards rear leaves pretty much) that was the only way i could do it without a rediculous amount of lift or frame chopping. If it was a 78/9 60 I could have sucked the hangars and shackles way up into the frame and made me life soo much easier. I have heard decent thinks about front shackle so ill give it a shot. Also my approach angle will be close to 90.
Thats where I figured my tire would be. And those are little 36s!
 

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With what gears though? I think im just gonna try and find an nv4500 and run that, should be fine.
Thats with 3.55's, but 30" tires. If you're running 42's, you'll be about 3% slower at that RPM. 11% with 39's, 20% with 36's. Many dodge's came with 4.10's, which is 15% less gear. They top out early, but will easily run on the highway. With the 4bt, some extra RPM might help running on the highway.
 

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Discussion Starter · #12 ·
Yeah tommorow I am going to talk to a guy about getting a 6bt. its heavy as shit but I think it will be fun
 

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A few early Dodges like mine use front shackles on front springs. It seems to contribute to a much smoother ride, even with fairly heavy springs and shocks.

There's a bunch of complicated physics involved but as I understand it, it allows the wheel to effectively roll up and out of the way of a road impact. Probably doesn't make sense, but that's how it works. It can be gentler to pinion angle variations also. It reverses the bending/flexion moments in the spring.
 

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It's my understanding that front shackles are better for hard stopping with light springs. They suck for most everything else.

Hence the reason 80 and up fords ride horrible with lift springs and the reason why shackle reversal kits (to put the shackles in the rear) are so popular.

I've run the later wide 60 front under a highboy and had no problem running highboy springs with shackles in the rear.

I just cut the rivets off the rear spring mounts, flipped them to the outside of the frame and cut a small slit through the lower frame lip for the inner shackle to slip through. The front crossmember was just a piece of 3/8" plate broken to the same spec as the factory crossmember, but 6" wider.

With the later axle I would recommend running the 80-97 Ford power steering box. The earlier boxes do not have enough throw to steer off the drag link.
 

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Discussion Starter · #15 ·
I am doing high steer with a hydro assist ram. Im not stoked on the front shackle setup but I will just apply more throttle I guess if it sucks when driving. :happyfinger:
 

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It shouldn't be that bad, sounds like you've got a pretty good handle on it.

When you get it going I'm also curious to see if you get the same undriveable lane switching death steering the 86 and newer F-350 4x4's get if you take the panhard bar out. I think the panhard bar is mostly there because they lack a front crossmember and the rigidity of the highboy frame, but I think the front shackles also contribute.
 

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Discussion Starter · #17 ·
I would think that would be from incorrect preload on the kingpin bushing. I just rebuilt all mine so well see hwo it goes. This king pins were fun to get off!!
 

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Well, not really. If you take the panhard rod out any 86-97 F-350 4x4 goes all over the road. Feels like your driving on flat bias ply tires.
 

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Discussion Starter · #19 ·
Looks like ill find out
 
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