Need guidance on 4 speed swap into a ‘65 FJ40 w/327 (1 Viewer)

Joined
Jun 8, 2010
Messages
16
Location
Salem, Oregon
I’m taking on a tranny/t-case swap into my 1965 fj40

Warning, I’m a novice so I’m sure I’ll say some things that require some grace.

What I have:
1965 FJ40
327 Chevy Conversion
Toyota
manual 3 speed tranny
Toyota T-case single stick (Not sure if it’s the original since it shifts in an L shaped pattern but my glove box instructions are in a straight line)

What I want:
Toyota 4 speed tranny swap
T-case that will play nice with the 4 speed (maybe that’s the one I’ve got or another)

Why I want it:
Don’t like the 3 speed. I need the rig to be a daily driver and be able to play somewhat nice for 5 miles of daily freeway driving. I’m not going to wheel it hard, but I want it to be up to the task of going up in the woods of Oregon and exploring past where most people can get. I want to do the conversion as easy as possible so I can actually accomplish it myself- hopefully Ha!

How you can help:

1. Direct me to good info/instructions on Mud for my swap. The search forums are still a bit confusing for me to navigate and when I get into one and the pictures are gone (grrrrr- the pics are what really helps my brain to get it).

2. Direct me to parts/adapters to get the job done.

3. WTB a 4 speed and t-case (if u think I need to replace my t-case)

Thx all!
 
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brian

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lebanon,pa
Why I want it:
Don’t like the 3 speed. I need the rig to be a daily driver and be able to play somewhat nice for 5 miles of daily freeway driving.


just an fyi, the 4spd top gear ratio is the same 1:1 ratio as a 3spds top gear.
 
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Rocky mtns
If you don’t have the 4 speed(toy) maybe look at a Chevy SM465. It’ll bolt up to your engine with a cheap Chevy bellhousing. You’d need an adapter to your transfer case, but that tranny/bell housing is relatively cheap and very strong. I hated the 3 speed in my 73 and swapped over the SM465 for that reason. It’s got three synchronized normal driving gears and a super low crawl gear. This is still a truck granny, so don’t expect silky shifting, but it was a definite improvement over my old stock 3 speed with unsynchronized 1st gear in town.
 

navydivedoc

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I have a 67 with a SBC conversion and the 3 speed, and I'm converting to a 4 speed, so really an identical job to what you are doing. Here are a few things that you need to be aware of.

1. The early trucks have a relatively small trans cover, and access hole, and this can lead to some need to fabricate to clear a trans depending on which one you use. You will need to work on it for shifter holes anyway. Sometimes the rear crossmember is a problem.
2. Your toyota options are the older 4 speed with the "1 piece" Transfer case, or the later 4 speed with the "split case". Split case is beefier, both in terms of its capability to withstand V8 power but also its size.
3. GM options are SM420 or SM465. Of those, 465 is definitely the better option. Keep in mind, this is really a 3 speed trans with a very deep (6:1) crawler gear. Great for offroad, but it's basically the same transmission you have now for day to day driving. Just a lot heavier. For a driver truck, not an offroad machine, the H42 Toyota trans is the best bet.
4. You will need to attach the SBC to the toyota 4 speed. The 3 speed bellhousing is not the same, so you can't reuse the adapter you have now. I am using the Advance adapters bellhousing, SBC to H42. These come up fairly often on the classified here. You will also need the clutch fork, pivot, and a couple of other small parts. I ordered mine from Mark @65swb45. I also now have a spare set of these parts from the 2F I just bought, so if you go this route I can help. Another option is a ranger overdrive. Direct bolt to Chevy bellhousing and the H42. Expensive.
5. Rear motor/trans mounts. Early 4 speed has motor mounts on the bellhousing, as does the 3 speed. You will lose these. Advance adapters makes a crossmember that bolts to the t-case. This can be used for either 1 piece or split, but is probably better for the 1 piece. I purchased an FJ60 crossmember for the split cae that I am using. This requires welding new crossmember mounts on the frame.
6. If you use the older FJ40 4 speed, your stick shift will be forward like your 3 speed is. This may interfere with the heater. If you use a later "short" H42 with a 60 series top cover, the stick is a bit further back and roughly in stock location as the SBC is forward of stock in most cases.
7. Drive shafts won't fit, but can be modified. I will order Tom Woods and just be done with that, and would recommend the same.
8. If you stay with the early Trans and T-case, you will still have an e-brake. Split case you will not.
9. Early 4 speed and t-cases are easily available and much cheaper than later H42 and split cases. For your described uses, buying an early 4 speed and t-case as a combo would be the least engineering and most cost effective solution.

I'm sure you'll have more questions, and others can help fill in gaps. Remember that both trans have a 1:1 final drive, so at speed there is no difference. 3 speeds are almost free as no one wants them, so if your V8 grenades yours, it's easy to replace. I'm a fan of the 4 speed, just realize it's a fair amount of engineering and $$.
 
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navydivedoc

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Nice analysis by @navydivedoc .
If you stay with the Toyota t-case the split case offers you the option of upgrading the low range gears without swapping out the entire t-case.
This is why I went with the split case. I had Georg @orangefj45 build me a short H42, split case with 3:1 gears and a twin stick, and an OEM split case drum brake upgrade. Exactly what I wanted, but this is not a cheap option. Whatever you need, Georg is a great resource for parts, rebuilds, etc.
 
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Kingman, AZ
I have a race-prepped Muncie 4-speed that was in my cruiser before the NV4500. That thing was a joy on the street. It shifted like a hot knife through butter.
 
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Jun 5, 2007
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Brea, Calif.
^^^^It also played hell on the transfer-case since it let high H.P. and high R.P.M. hit the tractor "side thruster" transfer-case, which seldom could actually handle it. Back in the day when guys were running the Muncies they were blowing 2-3 transfer-cases per year- - -sad story. And this is not to mention their crappy off road gear ratio.
 
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Joined
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Kingman, AZ
It worked fine for my needs at the time. My 327 came out of a school bus. I think it was the V8 version of an F, low HP, low RPM.
 
Joined
Jun 8, 2010
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Location
Salem, Oregon
Thanks for your patience with my responses- busy week!

So, this information is super helpful and I have some good clarity about what I want. I’m going to go with the early H42 tranny with 1 piece transfer case. I’ll need to source the appropriate adapters etc and do some fabrication to get it all in. Love the suggestions about other trannys- I’ve had the sm465 in another rig.

My next questions are:
1. Will my current t-case work with an older H42 (remember it seems to have been swapped out at some point as it is a single stick)?
2. As I’m shopping H42’s is there a write up on mud you like for how to identify an early vs a later one?

Thanks again all, esp @navydivedoc
I know what I want, now I just have to find it- I’m on my way!
 

navydivedoc

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Aug 20, 2015
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Maine and New Hampshire
Thanks for your patience with my responses- busy week!

So, this information is super helpful and I have some good clarity about what I want. I’m going to go with the early H42 tranny with 1 piece transfer case. I’ll need to source the appropriate adapters etc and do some fabrication to get it all in. Love the suggestions about other trannys- I’ve had the sm465 in another rig.

My next questions are:
1. Will my current t-case work with an older H42 (remember it seems to have been swapped out at some point as it is a single stick)?
2. As I’m shopping H42’s is there a write up on mud you like for how to identify an early vs a later one?

Thanks again all, esp @navydivedoc
I know what I want, now I just have to find it- I’m on my way!
You'll have to post up pics of the t-case to see what it is. The 3 speed t-case is not a direct bolt up to the 4 speed, so it's probably best
to just source a mated H42/1 piece trans. They can be had quite cheaply. Then you also know that you have an early one. Reseal, drop it in. I'll send you a PM re: clutch and adapter parts.
 

mattcamp

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Portland/Vernonia Oregon
You can get a 16 spline gear that will let you keep your transfer case and use it behind a 4 speed, it has to be an early 4 speed basically from the 70's not the 80's. That gear will be roughly 150 bucks, so if you find a 4 speed with a transfer case attached, thats great, but if you just source the tranny you have the option of using your t-case. Basically you should do a lot of reading because going 3sp to 4sp is very common and there are many ways to do it.
 

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