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The th400/Np205 combo I picked up had the "long" output on the th400 that needs to be swapped out for a shorter version. So I went ahead and ordered a new output (th400/np208) from Advanced Adapter.
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I found a guy that is somewhat local and pretty well known on Pirate that I'm going to use for the output swap.
 
as future reference for anyone doing a crawl box, you want a transmission output that is flush or just short of the end of the adapter. I thought I ordered the wrong output (pictured above) but after a quick talk with NWF they confirmed I want the th400/NP208 output that has a 2.4" stick out that matches the 2.4" thick np208 adapter. There is a shorter th400/np203 output that's 1.4" of stick out.

Transmission is getting dropped off tomorrow, hopefully he doesn't find anything else in the transmission that needs attention.
 
Transmission was dropped off after work today, I'll know Saturday how it looks inside....

Also ordered the np205 rear support from DIY4X.
 
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Also ordered the np205 rear support from DIY4X.

Money well spent. There are a couple ways to do it but iirc the plate is asymmetric and only goes on in one orientation so you need to bolt it up before tacking your tube on to make sure you have it right. My build has some detailed pics of how I used the support kit if you want some reference. I will be using your 241 eco box build for reference later myself if I build the Raider like I was planning
 
After breaking the other adapter I want to make sure the drivetrain is supported sufficiently. I think I saved some of your doubler/crossmember photos, need to look again.

I'll make sure the Eco Box is documented well.
 
After breaking the other adapter I want to make sure the drivetrain is supported sufficiently. I think I saved some of your doubler/crossmember photos, need to look again.

I'll make sure the Eco Box is documented well.

Cool, looking forward to it.
 
I was just going through your thread, those pics are very helpful, thanks.

1.5" square tube? .120 or .180?

I'm not sure if I'll end up as flat as you are.
 
I was just going through your thread, those pics are very helpful, thanks.

1.5" square tube? .120 or .180?

I'm not sure if I'll end up as flat as you are.

The other way you can do it is put the tabs off the plate and then have a single piece of tube come off your crossmember and hold the sleeved bushing. I think my method is way stronger than that method though.

My crossmember is 2" square 1/4 wall. I went that heavy with it because it serves 3 purposes. (1) rear case support (2) antiwrap bar shackle mount (3) belly skid rear mounting point. If you are only doing the rear case support then 1 3/4 - 2" .120 wall round tube should be fine
 
Why not use the two bolt holes that are already their for the factory brace?:dunno::thinking:
 
The other way you can do it is put the tabs off the plate and then have a single piece of tube come off your crossmember and hold the sleeved bushing. I think my method is way stronger than that method though.

My first thought was using the tabs off the plate, I won't really know what makes sense until it's up under the rig and I can start to lay things out. I have another mount between the Np205 and the crawl box so this mount won't be carrying the same loads as yours (in theory at least).

My crossmember is 2" square 1/4 wall. I went that heavy with it because it serves 3 purposes. (1) rear case support (2) antiwrap bar shackle mount (3) belly skid rear mounting point. If you are only doing the rear case support then 1 3/4 - 2" .120 wall round tube should be fine

I won't need to integrate the Anti-Wrap into this however it will need to be redone since I'm adding roughly 11" of drivetrain length which will require my ant-wrap crossmember to move up and back farther. I really wish I would have bought the anti-wrap that was offset on the pumpkin for the "k5".

OK, 1.75" .120..... I've been debating lot's of different designs but I'm pretty sure I'm going square tube but the size of the tubing seems to vary between 1.5" and 2" for the trans/doubler crossmember.

Lot's of info and pics in this thread https://ck5.com/forums/threads/the-mother-of-all-doubler-crossmember-pics-thread.233677/

Here is a few that I liked for the the simplicity, again I'm not sure what my belly height which will impact the design a bit.

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@K85 Octane
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You can I just don't think that's the better design. Some also go off the PTO cover...

I think that would be an OK option but you would still have to figure out a way to isolate it ie a poly trans mount or something

They are probably all good options, but I am going to just use the two bolts off the side and a diyx4 poly mount with a 2" sq tube cross member. Just real simple. Whenever I get back to it. Lol

It will be good enough for a camping truck.
 
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They are probably all good options, but I am going to just use the two bolts off the side and a diyx4 poly mount with a 2" sq tube cross member. Just real simple. Whenever I get back to it. Lol

It will be good enough for a camping truck.

I know some people have broken adapters and blame a side mount that tied off to the frame. With a lot of frame flex I guess it's possible....I'll keep my mounts running down the center of the crossmember.
 
Those designs above all look pretty decent. I believe the tabs that come with the kit have a 2" base length so if you mount them to the crossmember then i'd go 2" square. Otherwise whatever you want
 
I know some people have broken adapters and blame a side mount that tied off to the frame. With a lot of frame flex I guess it's possible....I'll keep my mounts running down the center of the crossmember.

Its worthwhile to look at bmxbryant9s support as well. Probably one of the best ive seen.
 
Its worthwhile to look at bmxbryant9s support as well. Probably one of the best ive seen.

yeah his is cool but he's running different style mounts and utilizes the stock crossmembers. He must drop the hole thing to service the trans/t-cases? I want my skid removable from the crossmember.
 
Its worthwhile to look at bmxbryant9s support as well. Probably one of the best ive seen.

I had to go back and look at his. While he did do a good job making it, IMO it is way more than you actually need and sits pretty low too. I think the skeleton style units already shown as examples above are the better option. I have had rigs with the big super heavy full belly skids and learned my lesson about them being a total PITA. I thought long and hard how I wanted to do this better on my 77 build and I wound up using a box tube structure that then gets a removable 1/4" plate bolted to it. It's the best of both worlds. You can unbolt the actual skid plate if desired and drop it separately, then you can remove the box tube structure if you need to drop a case or something. The rear cross member is the last thing to come out. This means you have 3 separate pieces: plate, tube structure, crossmember. Making it modular like that gives you a lot more options and makes installation and removal way easier because you are breaking all that weight down into manageable individual parts.
 
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