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R150F to transfer case question

Toyotaguy

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Guys sorry for the newb question.

I have a 94 runner that I just swapped a R150F in. The transmission is 23 spline output. I found a gear tcase locally for cheap but it's 21 spline. I really don't want a 21 spline tcase.

Can I swap the input shaft and convert into a 23 spline? How much stronger is it?


I really want to run a AA adapter and run a Atlas but I haven't decided to spend that much money on a Tcase just yet.
Thanks
 
Yes
but marlin is outta stock so trail gear.
Think about long range cost of doing a doubler ect. Vs atlas now...

to coin a phrase oft used



Sirch newb:flipoff2:
 
R150 will have a chain drive case, you'll need an adapter and a gear drive 23 spline input. No advantage at all if you aren't doing duals or a 4.7 gear at the same time. If you do a 4.7 gear, you just order it with a 23 input.
 
Guys,
I do plan on the 4.7 reduction which is the whole reason for the tcase swap. I'm just not sure I'll be happy with a stock gear case 4.7 swapped. I'm running 1 tons with 40's and will do an engine swap later down the road.

I personally believe my tcase will be a weak link if I go with a stock 4.7 swapped case. Some people say they are super tough and some say if you're running larger axles and tall tires it'll still break.
 
You should go up top and fill in the ENTIRE plan so we can give good advice..
sight unseen I think, 4 gear atlas tighter package and marginally more $$$

first pick eng. Then build rearward.
 
Id just go Atlas now. buy once cry once. I did the same thing just wished I would have went with a 4 speed instead of an Atlas 2.
What is your current engine a 3.0? Planning on going to a 3.4?
 
Id just go Atlas now. buy once cry once. I did the same thing just wished I would have went with a 4 speed instead of an Atlas 2.
What is your current engine a 3.0? Planning on going to a 3.4?

Current engine is the 3.0. Planning for a 3.4 later. The build is taking all my extra cash right now. Engine swap isn't in the budget right now.
 
Swap back to A340 and go atlas 2 speed. 4 speed if you keep the R150F.
 
Id just go Atlas now. buy once cry once. I did the same thing just wished I would have went with a 4 speed instead of an Atlas 2.
What is your current engine a 3.0? Planning on going to a 3.4?

How much of a trail rig will it be? An atlas gets into the floor for the passenger seat.

that’s where I’m at in turning my 4runner into a
Chevy truck :flipoff2:
 
Axle gearing makes a big difference. For some reason there was a big trend ~10 years ago where everyone thought it was cool to put 1 tons and 40-44s on their toyota, but leave the 4.10s in the axles. This puts crazy stress on the tcases.

On the other end of the spectrum, I know a local guy who put 1 tons with 7.17s in his toyota and has ran 42-49s for 10 years with bone stock tcases and no issues.

I ve ran them through a lot of shit in my old tubed samurai on 37 stickies and 4.10s (broke 2 rear out puts being dumb) and my heavy 4runner with 35-42s (twisted 1 front out put with 4.10s and 39 stickies, being dumb)

Toyota cases are strong, and will hold up to a lot. But they have a point where they don't make sense. As tcases get harder to find, and more and more people are building rigs where you need an adapter to run them, plus 2 donor cases, atlas looks better and better. I have a hard time running them behind anything bigger than a 4cyl.

I wouldn't bother with a single 4.7 honestly.
 
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Axle gearing makes a big difference. For some reason there was a big tread ~10 years ago where everyone thought it was cool to put 1 tons and 40-44s on their toyota, but leave the 4.10s in the axles. This puts crazy stress on the tcases.

On the other end of the spectrum, I know a local guy who put 1 tons with 7.17s in his toyota and has ran 42-49s for 10 years with bone stock tcases and no issues.

I ve ran them through a lot of shit in my old tubed samurai on 37 stickies and 4.10s (broke 2 rear out puts being dumb) and my heavy 4runner with 35-42s (twisted 1 front out put with 4.10s and 39 stickies, being dumb)

Toyota cases are strong, and will hold up to a lot. But they have a point where they don't make sense. As tcases get harder to find, and more and more people are building rigs where you need an adapter to run them, plus 2 donor cases, atlas looks better and better. I have a hard time running them behind anything bigger than a 4cyl.

I wouldn't bother with a single 4.7 honestly.

I remember that thread. I learned a lot about matching the ratios.

personally I think 37s and under should be toy cases. 40s can be adult driven. More than that and you don’t need Toyota drivetrain.
 
I’m in the “just do the Atlas now” crowd.

I know you won’t and you will be back here later in life telling someone else the same thing we are telling you now...
 
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Since were just throwing out opinions.

A R150 with an AA adapter is stupid. Just run an ax15 with a r150 input.
 
Guys,
Little update since I started the thread.


I found I local Toyota guy who has TONS of early model pickups, 4runners, LC's, transmissions, transfer cases, frames, cabs etc. I bought 2 gear driven t-cases from him for $350. Since I found them so cheap (IMO) I'm just going to run the dual Toyota cases.

Dual cases with 23 spline input gears, 4.7 gears in the rear case, and 5.38's in the axles I think I'll be fine. We'll see if I regret not going with an Atlas later down the road. I don't plan on a V8 swap. IF I motor swap I'll run a 3.4L.
Thanks guys.
 
Don't forget the chromo out puts! :flipoff2:​​​​​​

I'm usually in the "just go atlas" crowd, but $4k is a lot to swallow in a pos toyota. You might reconsider once you order everything you need.
 
Side note


Who would actually buy a Toyota crawl box to np 205 adapter?
​​​​​​
I looked into it when I was doing 1 tons in my 4runner. I was looking at the AA toy to D300/atlas adapter and a nwf 23 spline input. The issue was that I've heard of issues with that adapter (it's a poor design imo, 2 piece) and the 23 spline input is expensive, plus why have 205 beef with only a 23 spline input.

I think it would be a great option, you'd just run 4.7s in the crawl box. 205 ain't care. Plus you could run the 205 in low for hauling ass or whatever without fear of breaking the input like when guys run their 2.28 crawl box in low.

The other benefit, and the reason I was looking was to go driver drop to run the cheap and plentiful SD60s.
 
How much of a trail rig will it be? An atlas gets into the floor for the passenger seat.

that’s where I’m at in turning my 4runner into a
Chevy truck :flipoff2:

Good point. My Atlas 2 is sitting in the pass side floorboard..

There are certain concessions to be made..

IMG_0237.jpg


IMG_0237.jpg
 
That and toyota guys are obsessed with a flat belly.

Having a 2" drop down belly is not that big of a deal. I actually know a guy who didn't like his flat belly. Too large of an area to turtle on.
 
That and toyota guys are obsessed with a flat belly.

Having a 2" drop down belly is not that big of a deal. I actually know a guy who didn't like his flat belly. Too large of an area to turtle on.

To the opposite end, I think people are too hung up on massive skid plates. Dont need a sheet of 3/16 rail to rail.
 
I have the budbuilt 1.5" lift skid, minimal floor cutting (its cut a little more now, drive flange was hitting in the back) . pretty happy with it. Ive had the weight of the truck on it, and it is bent a little after 4 years. I think if I did it again, using the FROR style mount/skid it i could have it mount in the same spot, and tuck up another inch or so.


MHCHZgfl.jpg
 
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That and toyota guys are obsessed with a flat belly.

Having a 2" drop down belly is not that big of a deal. I actually know a guy who didn't like his flat belly. Too large of an area to turtle on.


Yea if I were to do it again, I would have built a subframe and left my floor in tact. Riding bitch in my truck sucks if you are tall.
 
I have the budbuilt 1.5" lift skid, minimal floor cutting (its cut a little more now, drive flange was hitting in the back) . pretty happy with it. Ive had the weight of the truck on it, and it is bent a little after 4 years. I think if I did it again, using the FROR style mount/skid it i could have it mount in the same spot, and tuck up another inch or so.

Those have issues as well, with just the rear housing as a mount, it will crack the 2nd to last housing piece.

Also, having the skid plate bolt directly to the cast aluminum case can cause damage on hard hits.

Imo, the best set up is the all pro type crossmember that grabs the rear and the stock mounts, then add a separate belly pan.
 
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