The Official 3rd Gen Dual Case, Dual Locked Thread

Ok. Gonna be a ‘noob’ here for a minute.

Guy near me is selling a R150 and transfer case from a 3.0.

The 3.0 had a chain driven; PSD case.

Looking at the pictures, it looks like the case is in 3 ‘parts’; like the gear driven case from the 4 bangers. And the front housing looks identical to my Lefty.


I should be able to take the front of the 3.0 case and bolt it directly up to my Lefty (gear driven case) for a doubler; right?

Or am I way freaking off?

I’ve tried looking; and can find information about the whole case; but not if I can use the front for a doubler or not.

The stock 3.0 chain drive case reduction box doesn't work. That's why companies like Marlin make adapter plates to convert them to gear driven cases.
 
Speaking of...

A few days ago, NorthWest Fab announced that they are developing a reduction box specifically for our Toyota chain driven cases, using the reduction section of a chain driven case rather than a gear driven case (link to Instagram post). I'll be watching this closely, it should simplify everything and come in at a more reasonable price point than current crawl boxes on the market.

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I’m in the process of ordering a 4.7 low gears for the top shift with front and rear adapters. Are you all putting the SR5 J shift TCase or the Limited H/L electric case? My truck is a 98 Limited with the H/L electric case. I’m in class and didn’t read the whole topic, just breezing through on the recent pages. Mahaloz in advance. [emoji1686]


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I’m in the process of ordering a 4.7 low gears for the top shift with front and rear adapters. Are you all putting the SR5 J shift TCase or the Limited H/L electric case? My truck is a 98 Limited with the H/L electric case. I’m in class and didn’t read the whole topic, just breezing through on the recent pages. Mahaloz in advance. [emoji1686]


Sent from my iPhone using Tapatalk

I believe only the j-shift case will fit unless you move the gas tank
 
Just a question for ensuring who’s done dual cases
I get it’s like a Swiss Army knife and more options is definitely better
BUT
Has anyone ever thought about or tired just doing a single transfer case?
Like an Atlas ?
Big reason that had me thinking this is because my brother has a taco with just an inchworm transfer case and that’s alone works just so well
So I guess I’m asking your personal opinions on pros and cons.
I don’t personally know anyone with dual cases.
 
Just a question for ensuring who’s done dual cases
I get it’s like a Swiss Army knife and more options is definitely better
BUT
Has anyone ever thought about or tired just doing a single transfer case?
Like an Atlas ?
Big reason that had me thinking this is because my brother has a taco with just an inchworm transfer case and that’s alone works just so well
So I guess I’m asking your personal opinions on pros and cons.
I don’t personally know anyone with dual cases.

It’s all personal preference really, there are ppl who have gone atlas. It’s a good option but I think it requires a bit more fab work to get it to fit nicely and it’s a tad more expensive.. Problem with doing a single gear drive case on our rigs is that the front driveshaft output is on the opposite side from the older trucks those cases come out of so unless you are doing a SAS it won’t work.. Pretty sure trail gear/inchworm had a ‘lefty’ case which is basically the older gear drive truck case with the front drive shaft output on the correct side but don’t think anyone makes them anymore..

I’d look into that northwest fab company. I messaged with him a bit on IG and if I didn’t already have everything for my Marlin cases I would’ve gone with that. The main benefit is if you use his case with a standard J shift case you don’t have to touch the gas tank or crossmember at all. Plus you can either use your stock case as a donor or find any 95+ tcase from just about any model toyota as the donor.. Probably much easier/cheaper than finding an old gear drive tcase..
 
It’s all personal preference really, there are ppl who have gone atlas. It’s a good option but I think it requires a bit more fab work to get it to fit nicely and it’s a tad more expensive.. Problem with doing a single gear drive case on our rigs is that the front driveshaft output is on the opposite side from the older trucks those cases come out of so unless you are doing a SAS it won’t work.. Pretty sure trail gear/inchworm had a ‘lefty’ case which is basically the older gear drive truck case with the front drive shaft output on the correct side but don’t think anyone makes them anymore..

I’d look into that northwest fab company. I messaged with him a bit on IG and if I didn’t already have everything for my Marlin cases I would’ve gone with that. The main benefit is if you use his case with a standard J shift case you don’t have to touch the gas tank or crossmember at all. Plus you can either use your stock case as a donor or find any 95+ tcase from just about any model toyota as the donor.. Probably much easier/cheaper than finding an old gear drive tcase..

Any useful info you gathered from the NW Fab company?
I've kept my eye on what they've been doing but it seems like a lot of R&D more than anything.
 
Any useful info you gathered from the NW Fab company?
I've kept my eye on what they've been doing but it seems like a lot of R&D more than anything.

I think he is taking pre orders, seems pretty legit to me.. If I build out a 5th gen someday I’ll definitely be using his setup. The main selling points were: quite a bit less expensive than Marlin/TG, you can use a newer tcase as donor which are way more abundant than the older cases and most likely less expensive, and you don’t need to touch the gas tank crossmember at all if your using an auto trans + j shift tcase. It’s adding 6.5” instead of 8.5”. Sounds like he will be coming out with an electronic shifter too so you don’t need to install triple sticks or cut another hole for a shifter.. I think but not 100% on this: manual trans+J shift tcase is the only option you don’t have to modify the gas tank crossmember for Marlin/TG?

The one thing about the Marlin/TG setup is you can get 4.7 gears instead of 2.28’s if you want to go that low. I’ve read some people say 2.56+2.28 is low enough (that’s what I’m going with). His setup will be 2.56+2.56 basically though.
 
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The un-good...

After 1 year of abuse....the un-good! Inchworm clockable adapter is loose...Anyone else had an inchworm clockable adapter failure? I'm going to pull it all apart and see what I'm looking at but my guess is the bolts that hold the clockable adapter in place are loose/broken. After the initial install I had some leaks where the adapter meets the crawl box and called Marlin...they assured me they used RTV on the mating surfaces and the clockable adapter was secured/locktite, etc. Now I am not so sure. Anyone else see this type of failure?

This could get exciting very quickly....see video in link.

Imgur: The magic of the Internet

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Problem solved…short story is the mounting bolts (30mm) that were shipped with the clockable adapter were bottoming out and not holding the adapter tight. Shorter bolts (25mm) installed..no movement now. Interesting the original Inchworm instructions I found online called for 25mm vs 30mm but Marlin told me the 30mm cleared on a set the tested in their shop. Not sure what happened, just glad it is done. More details here: https://www.toyota-4runner.org/3671885-post213.html

Anyone that orders inchworm adapters…recommend you double check clearance…sounds likes this is not a typical problem…
 
I know this is a shot in the dark (and off topic for this thread), but if anyone has the OEM front and rear driveshafts for a v6 manual I would be interested in buying them.
 
I swear I read someone bought a pre assembled arb locked front diff somewhere online. Can’t seem to find any information now. Any help?
 

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