Box4Rocks to BW4472?

[photo_van]

I ran across a post Lifted Dean made back in '07 regarding a gear reduction you can put in front of the transfer case. It uses the low range portion of the NP 231 transfer case. bolts up between the trans and transfer case. The overall length remains the same so no drive shaft modification. This is a popular box that the rock crawler guys put in front of their 231's to get 11:1.

Sounds like a possible option for low range AND AWD. My question to all you smart guys out there; do you think the BW4472 would hold up to the increased torque from the low range?

[mdmead]

I'm not saying a person couldn't break it, but this same basic case holds up pretty well behind boosted Syclones/Typhoons. Strength wouldn't be my worry. But is this conversion possible? (Interesting idea if it is...)

[photo_van]

Ok, thanks Matt. Im not familiar with Cyclones and Typhoons, do they put out twice the torque of our V6's?

I'm getting serious about this, but I sure would like more input from people; good idea? Bad idea? This just seems easier than putting in a 242 or other AWD Jeep case that requires a change in the trans output shaft (which requires pulling the trans?).

I don't see how it wouldn't work as the adapter is designed to work between a 4L63 and an np231. Many spine counts are available in the adapter kit including 27. I was wrong re. the length, it adds just over 7 inches (so rear shaft shorter, front longer) and there would be a bit more weight cantilevered behind the mount. There appears to be plenty of room aft of the existing tc and the front shaft would clear the cross member. I've already got the NP231 I can butcher for the low range.

This setup would retain the BW4472 which is a reliable case? After 30+ years of living and driving in mountainous snow country, I can honestly say my AWD Astro is the best snow vehicle I've ever owned; Toyota 4x4 pu and two Subarus. (I'll tell you the story of my Van breaking trail w/o chains beyond a fully chained, augured in Landcruiser wagon sometime). That's why I'm going the extra effort to retain the AWD. It will end up costing about $600, but could be well worth it.

ANY additional input would be greatly appreciated!

Thanks

[LiftedAWDAstro]

I don't know what input torque limit the 4472 has but as long as you don't hammer on it while in low range, you'll be good to go. The weaker parts are the front and rear diff's. I have chipped teeth in the front without hammering on the van. I did have a 231 and it was in low range when they broke. I drove it for a while before finding the broken teeth.

[photo_van]

Thank's for the input Dean. I saw somewhere the photos of your torn up ring gear. I plan on keeping my front tires on the ground so maybe I'll be OK Mostly I think it will be kinder to my trans for the things I already do as well as making me a little less anxious when I drop into those places that I'm not sure about.

Pretty light duty for the most part.

[LiftedAWDAstro]

Yeah, you'll be ok then.

[snapple]

Could you post up any links for parts and/or info you know of for this project?
Thanks!

[mdmead]

This setup would retain the BW4472 which is a reliable case? After 30+ years of living and driving in mountainous snow country, I can honestly say my AWD Astro is the best snow vehicle I've ever owned; Toyota 4x4 pu and two Subarus. (I'll tell you the story of my Van breaking trail w/o chains beyond a fully chained, augured in Landcruiser wagon sometime). That's why I'm going the extra effort to retain the AWD. It will end up costing about $600, but could be well worth it.

I'm with you on the ability of these vans in the snow. Best on road snow vehicle I've ever owned. (My list of 4x4s include Samurai, Ranger extended cab 4x4, Mazda (Ranger based) extended cab 4x4, Ramcharger, a couple of classic Broncos and F-250 Super Duty extended cab.)

I think I could give up the solid lock of a true 4x4 transfer case if I could get the low range as you mention. I never felt like front vs rear traction with the AWD was limiting. My issues have always been ground clearance followed by tranny stress from moving slow under load. I've been looking for an option with AWD that didn't include a bunch of electronics (like the new transfercases).

[photo_van]

I've been amazed at where the Astro has taken me without low range, I too don't think the AWD is a limiting factor whatsoever. But I do think my trans has taken a beating as I have basically been substituting the "slip" in the automatic trans for low range. I don't know much about automatics as this is the first I've owned, but it just doesn't seem like it can be good.

Also there are some places I just haven't gone as I'm not sure if I'll get out without low range. As far as snow, it has been the best hwy AND deep snow vehicle. It is our daily winter driver, we live in the snow, I don't want to give up the AWD.

There is a glitch in the Box4Rocks that I'm not sure can be over come. Because the BW4472 is a short case, the front output protrudes beyond the front face of the case. This is creating some significant clearance issues involving the front output flange and the gear reduction (231) case. Because of the asymmetrical 5 bolt pattern, that box can't be "clocked". However, I think the tailshaft to trans is six bolt. If that can be clocked along with the 231 then the tcase will clear.

Stay tuned.

Anyone know if the tailshaft housing is symmetrical 6 bolt? Can it be rotated?

[photo_van]

Could you post up any links for parts and/or info you know of for this project?
Thanks!

The Box4Rocks guy doesn't have a website, so most of the info I got was via a Google search. But here is a link to the the owner explaining the product and some photos
http://www.pirate4x4.com/forum/showthread.php?t=696803

[photo_van]

Looks like end of story re Box4Rocks in front of the BW4472; he no longer makes a 5 bolt kit.

[mdmead]

That's too bad as this seemed like a route I'd have been willing to follow.