R151F Tranny with Split T-case Question

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I'm not sure where this should be posted but I thought this might be a good place.

I was looking through a FSM for the R151F tranny and noticed that it also covered the split t-case. I've alway thought that the R151F was only used in turboed minitrucks mated to the standard minitruck t-case. What was unusual about the setup was that the T-case had its own separate input shaft rather than having the output shaft of the tranny pass all the way through the t-case as is the case with A440F, H41 & H55F. The R151F output shaft is coupled to the split t-case input shaft with a splined sleeve that slided over both.

Does anyone know what year/model of Toyota used the R151F/Split T-case combo?

The reason that I'm interested in this setup is that I may be able tp adapt it to mate the Isuzu MSA 5-speed tranny to the split t-case using a similar approach. The MSA tranny is used behind Isuzu 4BD1/2T diesel engines.
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the R151 used the split case from 1985+ in the LJ series land Cruiser...
 
I have a little experience with the R series to split case. We have a customer in Russia who has set a few of these up with our ToyBox kits. They were LJ73's. I'm still waiting for him to send us the tail housing and the "input shaft" cores that we purchased for samples. The "input shaft" is 23 x 19 spline. The 23 spline is identical to the US R151F (turbo trans) and R150F 23 spline out put shafts. Hope this helped.
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So CruzrDave, would that be a Marlin Crawler ToyBox you're referring to:flipoff2:

Good to see you lurkin' around here. :cool:

Phil
 
I have a little experience with the R series to split case. We have a customer in Russia who has set a few of these up with our ToyBox kits. They were LJ73's. I'm still waiting for him to send us the tail housing and the "input shaft" cores that we purchased for samples. The "input shaft" is 23 x 19 spline. The 23 spline is identical to the US R151F (turbo trans) and R150F 23 spline out put shafts. Hope this helped.

Thanks! That is exactly the information that I was looking for. So, for the R151F/Split-case combo, the rear R151F housing is different as well as having an "input shaft"

I had already worked out a simple coupling between the output shaft of the Isuzu MSA tranny and a 23-spline Toy shaft (thanks to Jim at Inchworm). I just need to fab the adapter that bolts the two together. Now, the only unresolved issue is finding a P/N for the "input shaft" for the split t-case and finding a source. If I can't get it in the US, I'll be in Costa Rica in January and might be able to get one there.

Thanks for the help guys! :):):)
 
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I have a little experience with the R series to split case. We have a customer in Russia who has set a few of these up with our ToyBox kits. They were LJ73's. I'm still waiting for him to send us the tail housing and the "input shaft" cores that we purchased for samples. The "input shaft" is 23 x 19 spline. The 23 spline is identical to the US R151F (turbo trans) and R150F 23 spline out put shafts. Hope this helped.

fxxx, i tried and tried to get in touch with Marlin for some answers on an auto to split case crawler package and gave up due to no response and now you are lurking here...
s***, i wish you boys could get your act together and respond. i have money to give you to help my wifes LJ78 off road...
 
My 2004 HZJ79 has an R151F in it, needs a rebuild - How much to rebuild one of those cruzrdave?

the R141 has the same gearing as the H41 or the H55F without the ID.. the tractor recieved this package and made a world of difference off road with out the noise of the custom gear t/case
 
****, i tried and tried to get in touch with Marlin for some answers on an auto to split case crawler package and gave up due to no response and now you are lurking here...
****, i wish you boys could get your act together and respond. i have money to give you to help my wifes LJ78 off road...

My original plan was to use a Toybox as the interface between the split t-case and Isuzu MSA tranny. Like Crushers, I tried several times to talk to someone at Marlin's to verify that this would indeed work but was never sucessful. That is why I'm now pursuing a direct link from the MSA to the T-case.

Marlin and Dave - please help me give you some of my money!
 
fxxx, i tried and tried to get in touch with Marlin for some answers on an auto to split case crawler package and gave up due to no response and now you are lurking here...
s***, i wish you boys could get your act together and respond. i have money to give you to help my wifes LJ78 off road...

Trying not to totally hijack this thread......

What model is the automatic?

When you say 'split case crawler' are you thinking ToyBox?

I know they have an adapter for the A340F (I worked with Marlin on it). I also know that the autos use a tailhousing to adapt for different purposes. The A340 series autos cam in different versions including 2wd. I would guess that the LC autos (A440 series?) would be similar.

During my research I found that there was a specific model of transfer case shared between the A340F and the V6-5sp (R151?). Since he had an adapter for the V6-5sp to gear driven mini-truck t-case, the same adapter worked for the A340F. The rest was working out the seals and coupler and VSS.

Maybe this helps....

Phil
(feel free to PM and I'll help if I can)
 
My 2004 HZJ79 has an R151F in it, needs a rebuild - How much to rebuild one of those cruzrdave?

Intersting .. here in Panamá al HZ engines come with H150 and HD engines with H151 tranny .. on other hand the FZ engines come mathed to H150 trannys or R151 ..
 
Intersting .. here in Panamá al HZ engines come with H150 and HD engines with H151 tranny .. on other hand the FZ engines come mathed to H150 trannys or R151 ..

In oz only the 1HZ have the R151 and the turbo diesel and 1FZ had the H151 from 99-06
 
Trying not to totally hijack this thread......

What model is the automatic?

When you say 'split case crawler' are you thinking ToyBox?

I know they have an adapter for the A340F (I worked with Marlin on it). I also know that the autos use a tailhousing to adapt for different purposes. The A340 series autos cam in different versions including 2wd. I would guess that the LC autos (A440 series?) would be similar.

During my research I found that there was a specific model of transfer case shared between the A340F and the V6-5sp (R151?). Since he had an adapter for the V6-5sp to gear driven mini-truck t-case, the same adapter worked for the A340F. The rest was working out the seals and coupler and VSS.

Maybe this helps....

Phil
(feel free to PM and I'll help if I can)
my problem was the output shaft is not a 2 pice but a one piece from the tranny to the t/case. i wanted to know if i could cut it to fit the marlin crawler box. the auto is a real slug at taking off when wheeling and i was planning on the crawler box to improve that. the stupid little truck ROCKS off road once moving but in snow or mud or taking off up a steep hill is wicked hard on the cooling system...pyro through the roof and cooling heading upward... i should also install a temp guage into the tranny to see how hot that bugger is really getting...

this would be nice since in Ontario it is either rocks or mud...
 
crushers your not the only one,,,, ive had such piss poor service from marlin that i only buy from them what no one else has. they still owe me a snap ring almost 6 months after the fact. i'm holding a $185 part hostage till they get me the snap ring,,,, so far looks like they dont want it.
 
it is so hit and miss, i know some guys in Alberta that have had great service from them... maybe they just don't need our money??
 
my problem was the output shaft is not a 2 pice but a one piece from the tranny to the t/case. i wanted to know if i could cut it to fit the marlin crawler box. the auto is a real slug at taking off when wheeling and i was planning on the crawler box to improve that. the stupid little truck ROCKS off road once moving but in snow or mud or taking off up a steep hill is wicked hard on the cooling system...pyro through the roof and cooling heading upward... i should also install a temp guage into the tranny to see how hot that bugger is really getting...

this would be nice since in Ontario it is either rocks or mud...

You probably already know this... the input on a standard gear driven reduction box is a splined 'stub' that the splined coupler fits onto. If your trans spline count is 21 or 23 then you could use a coupler.

The ToyBox uses a custom input gear that is internally splined to accept the trans output shaft. Obviously, the spline count on your trans would have to match one of his current input gears. The ToyBox page on his website will give you the applications. I think it's 10 and 19 spline. You could cut the output to fit. As a matter of fact, that is what is done for H41 & H42 trannys. (I have this setup on my bench now)

Then there is the adapter issue. Do you already have a plan for that?

Lastly there is the seal between the auto trans and the ToyBox. Obviously, you don't want any mixing going on in either direction. In my build, we used the original seal at the back of the auto and added another at the front of the reduction box. The tailhousing on the auto is empty. I added a small drain plug in it so I could check for seal leakage. For a Toybox application, this becomes a little more problematic because of the input difference.

You are in about the same place I was back in 2000.

Here are the two articles I wrote back when I did it.
http://www.4x4wire.com/toyota/tech/autocrawler/
http://www.4x4wire.com/toyota/tech/autocrawler/index2.htm

Phil
 
most of my research is at the new location and i will not be there till Jan.

the tranny code on my auto is the A343F.
i followed this build: http://www.lextreme.com/forums/showthread.php?t=2653 and ran into some questions, the 343 has the full length output which seemed different from the A340 and the A341. this is where i ran into a road block.

i wanted a doubler or the rear low gearing, either or. i had a t/case sitting here, i have the usual 2 piece stock case as well, i just needed the adapter from the auto to the toy doubler... i am not big into adapters but with their reputation i thought it would be a good part...

oh well, one day i might get it done... the wife woudl be happy with a crawler gear since she loves her wheeling rig but not the "off the start" performance...
 
most of my research is at the new location and i will not be there till Jan.

the tranny code on my auto is the A343F.
i followed this build: http://www.lextreme.com/forums/showthread.php?t=2653 and ran into some questions, the 343 has the full length output which seemed different from the A340 and the A341. this is where i ran into a road block.
I'm not an expert on autos but I guess you might be able to build a 340 with a 343 rear housing, or if your 343 output is specific to a cruiser, use a 343 from a surf, which would more than likely be compatible with the US domestic runners which use the same chain t-case. (or just swap the output shafts from one to another ?) From there use the tacobox adapter to the gear reduction box and then the rear toybox adapter to a H41 split case ?
 
in snow or mud or taking off up a steep hill is wicked hard on the cooling system...pyro through the roof and cooling heading upward... i should also install a temp guage into the tranny to see how hot that bugger is really getting...

Is the tranny cooler built into the bottom rad tank ?
 
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