Dual case options (1 Viewer)

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Joined
May 31, 2011
Threads
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Location
Fountain Hills, AZ
I'm in the process of researching out a dual transfer case configuration for my truck. I'd like to know what the consensus of choice would be. I've contacted Marlin about the toybox several times and no response, and I've also contacted NorthwestFab about the blackbox for landcruisers and have heard nothing in reply, also the page for the landcruiser black box has no information.

There was a thread for a club down in Florida about installing the toybox, but the pertinent links for the assembly are the way of the dodo.

So what are the options for a dual case setup? I know about Marks replacement gears but that basically makes for a 1:1 output or super-low output, with no steps in between. Klune is out of business or bought out(from what I can tell) so, that is not really an option either.

What solutions have the rest of you come up with?
 
I'm in the process of researching out a dual transfer case configuration for my truck. I'd like to know what the consensus of choice would be. I've contacted Marlin about the toybox several times and no response, and I've also contacted NorthwestFab about the blackbox for landcruisers and have heard nothing in reply, also the page for the landcruiser black box has no information.

There was a thread for a club down in Florida about installing the toybox, but the pertinent links for the assembly are the way of the dodo.

So what are the options for a dual case setup? I know about Marks replacement gears but that basically makes for a 1:1 output or super-low output, with no steps in between. Klune is out of business or bought out(from what I can tell) so, that is not really an option either.

What solutions have the rest of you come up with?

I have a Toybox in mine. I use the 4.7:1 low most of the time and love it. I also like that the drive shafts on a MWB 70 series are nearly exactly the same length.
 
I've been working with NW Fab to develop the Land Cruiser blackbox, and loaned Kyle quite a few different transmissions to mock things up with. I haven't heard anything for a very long time and I have yet to see the prototypes on my doorstep.

Marks Gears: there are underdrive (about 8 - 9%), overdrive (about 8 - 9%), and 1:1 options for high range, and then two different options for low range depending on what you select for your high range options. I do not in any way consider a 3.05:1 low range ratio to be a super-low output ratio. Some cases will require grinding, and others not - seems to depend on the vintage of the casting.

Advance Adapters: has a 4:1 low range gear set with a high range or about 10% reduction available for the split case. This gear set does require a fair bit of machining to the case halves. (talk to Georg Esterer - aka OrangeFJ45 here in Mud - he deals in these units)

Marlin Crawler - has been notoriously hard to get through to (I've essentially given up in trying to deal with them), and they have not been forthcoming with producing the Land Cruiser ToyBox in any significant numbers.

~John
 
Ok, just had a long-ish conversation with Kyle at NW Fab - most of the parts are made up, there is a shaft at the shaft cutter waiting to be completed and then the prototypes will be coming out (he says it should be a a few weeks - but I'll wait and see how that shakes out)

We will be a dealer for these once we have the testing done and the adapters are proven.

The additional length will come up to about 7.5" and it will require cutting the tail shaft of the transmission shorter to fit into the blackbox adapter.

The reduction ratio will be 2.72:1 and will multiply whatever gears you have in your system (ie: H55F 4.84 x split case first gear ratio [either 1.96 early, or 2.26 late] x diff ratio [either 3.70, 4.11 or 4.10]).

Your BJ73 would go from 38.97 to 106.0 in first gear low range.

I will post up more info once this has all been sorted out.

~John
 
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Thanks for the update John, I sincerely appreciate it. I'm about 4 hrs from finishing up my SOA(thx Arizona h3ll heat) and I'll do a commentary about it when I am done--not a write up per se.

I will be most definitely interested in running a black box once they are ready for prime time, hells bells I'd run it as a test vehicle if they want to send me one.

The gear ratio I'd be running would make for this to be a good crawler vehicle as it were. I'm not interested in running the Hammers but I want this do be a dual purpose vehicle, somewhat daily driver and weekend crawler/explorer truck. I just had JT differentials do a gear change(4.11-4.56) and dual TJM PRo lockers. Coupled with this last modification, the black box would work out pretty d@mn good.
 
It's being designed to work with both the H55F and split case and the A440F and split case.

The 80 series does not have enough room to allow for such a long extension of the transfer case rearward without making some very significant changes to the vehicle. If you crawl under an 80 series and have a look, it will be very apparent as to why.

There are low range gear options for the 80 series - Mark's Adapters makes some.


~John
 
It's being designed to work with both the H55F and split case and the A440F and split case.

The 80 series does not have enough room to allow for such a long extension of the transfer case rearward without making some very significant changes to the vehicle. If you crawl under an 80 series and have a look, it will be very apparent as to why.

There are low range gear options for the 80 series - Mark's Adapters makes some.


~John

John,

I hear you. Needless to say, my application is not a stock 80. I actually need a 5-6" extension of my drivetrain to get the transfer case to stay in the stock location.

I wonder if the split case and the HF2AV share the same input/bolt pattern? Seems like that would be half the work of making a black box that mates a toyota case to a GM trans.
 
i have a toybox in my hzj79 and i have the 4:1 gears in my HZJ74. The 4:1 gears are not quiet. The HZJ74 isn't quiet either, but the gear noise is noticeable. It's on par with an old 3-speed FJ40 case.

the Toy box is quiet. BUT, I've had a small issue where the 4.7:1 gears are such a tight fit that it starts a hydraulic pumping effect and pushes some oil out the shifter. The issue is not consistent with all Toyboxes... marlin says it's a little hit more miss. They have also redesigned their adapter plate to help reduce the pressure... BUT, they didn't machine the new plate enough for 5th gear (had to pull it apart and machine the plate).

(Hey Lowenbrau, have you had any issues with your crawler? I know you've had yours a long time.)

If you don't mind a little noise, the 4:1 kit is cheap, fast, easy... and low. Send your case halves to AA, and they will machine it correctly.
If you want some real man's crawler gears (kidding), get the toybox. 207:1 is silly slow.

If you can't get hold of Marlin or AA, Georg at Valley Hybrids is a dealer and can order/drop ship it for you. He seems to have a knack for getting in touch with them.
 
Georg mentioned that the high range ratio is about 1.1:1 - is that correct? In most of my applications I want to maintain the current high range ratio, not lower it.

I'll talk to NW Fab about other options for the Blackbox in a while and update as I get more info.

~John
 
on the 4:1 kit for the split case? Huh. Didn't know that (and haven't noticed a change in RPM... oh wait... no tach...hmmmm). I assumed it was 1:1 for the new AA gears. hmph.
 
Georg mentioned that the high range ratio is about 1.1:1 - is that correct? In most of my applications I want to maintain the current high range ratio, not lower it.


~John

This surprises me a bit. Generally by the time someone is jonesing for lower low range gears it is because he's running bigger tires and could uses some help in the high range as well to avoid having to replace the gears in his diff. I sure wouldn't mind about 10% less overdrive but I'm still running the 4:11s. Fortunately for me having all the low range options makes the high range a small issue. I use 4th and 5th interchangeably on the highway depending on headwind.
 
(Hey Lowenbrau, have you had any issues with your crawler? I know you've had yours a long time.)

I have had it for a long time but very few miles. I piled up the H55f in the way to the arctic and the rig sat for nearly two years before I resurrected it. I'm daily driving it now and not having the oil problem though Peter (behemoth60) has a Toyboy from the same batch and his leaked until marlin sent him some new parts this year. (top cover or shifter seal?) He's on his way home from Moab as we speak (drove there on 41" tires) so we'll hear how it did soon, I'm sure.
 
gifu said:
on the 4:1 kit for the split case? Huh. Didn't know that (and haven't noticed a change in RPM... oh wait... no tach...hmmmm). I assumed it was 1:1 for the new AA gears. hmph.

Gifu what trans and transfer are you running with your 74?
 
1HZ/H55F/splitcase with 4:1 kit.

stock 4.1's

running either 255's or 295's depending on mood, weather, destination, Venus crossing, etc.
 
gifu said:
1HZ/H55F/splitcase with 4:1 kit.

stock 4.1's

running either 255's or 295's depending on mood, weather, destination, Venus crossing, etc.

Marlin kit?
 
I have had it for a long time but very few miles. I piled up the H55f in the way to the arctic and the rig sat for nearly two years before I resurrected it. I'm daily driving it now and not having the oil problem though Peter (behemoth60) has a Toyboy from the same batch and his leaked until marlin sent him some new parts this year. (top cover or shifter seal?) He's on his way home from Moab as we speak (drove there on 41" tires) so we'll hear how it did soon, I'm sure.

I have the Toybox with 4.7 gears, and have had it installed for almost 8 years now. This particular box was amung the very first 5 that came off Marlin's assembly line, if my facts are right.

I have put a lot of miles on mine. It has ALWAYs pumped oil out the top shifter hole. I have replaced seals and shifter boots, and it has been a constant problem, including again on this recent trip to Moab. Finally with a free afternoon in camp, Marc (Shaker) came up with a crazy idea to make a seal from a piece of shower hose. After several revisions, we stuffed some hose down the top of the Marlin, and put the shifter down through the hose into the shift fork... and guess what... it no longer leaks out the top. But, now it leaks somewhere else. I cannot determine whether it is a related problem or not.

I have rebuilt my Toybox last spring.... I have had ongoing problems with keeping oil between my tranny, marlin, and transfer case, and on the trip to the arctic, ran the marlin and tranny low on oil and ruined some bearings. I rebuild all three cases, and thought I had the seals fixed. But this trip to Moab proved I did not. Quite frustrating.

However, the performance, and the gear choices, are fantastic. On the sandy smooth roads, I use 1.89 low range. For rough and rocky, the 4.7 low provides great gearing. For crawling, the double low is... almost too slow to use 1st gear... 1st gear double low is quite ridiculous. I will generally run 2nd or 3rd gear double low,and reserve 1st gear ultimate low for dropping wheels off ledges.

Frustrating with the whole oil situation, but I do love the performance.
 
This surprises me a bit. Generally by the time someone is jonesing for lower low range gears it is because he's running bigger tires and could uses some help in the high range as well to avoid having to replace the gears in his diff. I sure wouldn't mind about 10% less overdrive but I'm still running the 4:11s. Fortunately for me having all the low range options makes the high range a small issue. I use 4th and 5th interchangeably on the highway depending on headwind.

It's because I like cruising at 120+ on the Interstates or when up north in Alberta... The tall 3.70s, with the 255 85R16s make for some good top speed. Corrected speedo: 2050 RPM at 100Kph and if I don't drive it like it's stolen, I can squeak 32 MPG (Imp) out of it.

...and that's why!

~John
 

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