3.3 Cummins FJ40 Install

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cumminscruiser

cumminscruiser

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I'll start a thread installing a 3.3 Cummins in my sons FJ40. I could use all the help I can get. I'm not new the the Cummins swap since I put a 6BT5.9 in my FJ60 almost 15 years ago. It's been an every day driver since then. Enough with that.

The 3.3 will be married to a FJ60 4 speed transmission and transfer case. AA makes a Chevy Toyota bell housing so I'll need to find an adaptor to the Cummins.

I would like to use a hydro boost for the power brakes, I found a Isuzu alternator/power steering pump I'll try using with the hydroboost.

More to come.
 
Fast Eddy

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That's not a lot of gearing for that little motor. I'd want a 5-speed and 3.70s.
 
Chamba

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Fast Eddy said:
That's not a lot of gearing for that little motor. I'd want a 5-speed and 3.70s.

At least. And a Marks overdrive too. With 4:11 and an h42, you'll Redline at about 65 mph (3200 is Redline on those right?). I suspect even at 55 your fuel economy will be atrocious as you'll be turning 2750rpm.
 
overpaid slacker

overpaid slacker

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I am going the ranger over drive route on my 76 fj40 / cummins 4bt. This buys me 27% over drive that I hope will be adequate. May be converting the 4:11 diffs to 3:70's as well.
 
duffontap

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Always thought the 3.3 would be a cool project. Ranger torque splitter would be a good option if your budget would allow, although people do complain about how rough they shift.

Taller tires and a 3.7 ring and pinion ratio would probably be enough for my use. With 3.7 gears and 33" tires, you'd be turning 2072 rpms at 55, and 2449 at 65. There are no speed limits higher than 55 mph where I live (Oregon coast), so being able to go 55 comfortably and 65 on the upper end would be ok with me.

Good luck!
 
cumminscruiser

cumminscruiser

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3.3 Cummins FJ40

Here is the FJ40 and 3.3 Cummins.
May run FJ60 axles with the 3.70 gears.
IMG 2009
IMG 2011
 
C

Charger383bb

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So the 4.11 gears and axles are going to swapped out with FJ60 axles so it will have the 3.70 gears. Oh yeah btw that is my rig I just can't work on it since I am in Afghanistan for the next 6 month + till I finish up my deployment.
 
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Charger383bb

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I'll start a thread installing a 3.3 Cummins in my sons FJ40. I could use all the help I can get. I'm not new the the Cummins swap since I put a 6BT5.9 in my FJ60 almost 15 years ago. It's been an every day driver since then. Enough with that.

The 3.3 will be married to a FJ60 4 speed transmission and transfer case. AA makes a Chevy Toyota bell housing so I'll need to find an adaptor to the Cummins.

I would like to use a hydro boost for the power brakes, I found a Isuzu alternator/power steering pump I'll try using with the hydroboost.

More to come.

*correction* Isuzu alternator/vacuum pump combo to use with the brakes till we figure out the hydroboost brake setup
 
bikersmurf

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4 speed w/ 33s yields 25%ish overdrive and nice gear spacing. I'm happy w/ it for west coast highways and a 350.

Where is the 3.3 happiest? (RPM wise)
 
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Charger383bb

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its peak power is at 2200 rpm, i don't remember its max rpm speed but it probably wont be much higher than the 2200 rpm since it isn't an automotive engine but it doesn't have the industrial injector pump.
 
Chamba

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cumminscruiser said:
Here is the FJ40 and 3.3 Cummins.
May run FJ60 axles with the 3.70 gears.

I've got fj62 axles under my LX and love them. The added width makes her drive like a modern car on the freeway and she feels much more stable off road due to the wider footprint. I also moved the rear axle back 2" and the front axle forward 9/16" (the most I could while still keeping the factory power steering setup).
 
cumminscruiser

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3.3 Cummins FJ40

For some reason I thought it was an alternator/ power steering pump so its a alt/vacuum pump. I'll put the hydroboos away for now and stay with the stock set-up.

Be safe son.
 
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PanchoM

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So the 4.11 gears and axles are going to swapped out with FJ60 axles so it will have the 3.70 gears. Oh yeah btw that is my rig I just can't work on it since I am in Afghanistan for the next 6 month + till I finish up my deployment.

Nice rig.
Thank you for serving .
 
DPV7070

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I did a lot of research on this route before deciding to go with a MB OM617 (mainly due to budget, availability, and durability). Check out Phoenix Castings & Machining for an adapter to the 3.3.

http://www.phxgrp.com/gmpowertrain.htm

There's also a guy, "Kleatus," doing a 3.3 swap on the board as well.

https://forum.ih8mud.com/40-55-seri...my-76-40-b3-3-swap-some-general-fixin-up.html

As an Afghanistan vet, I appreciate your son's service. Tell him to keep his head down and get back home.

Dave
 
cumminscruiser

cumminscruiser

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3.3 Cummins FJ40

Pheonix casting is the next step, just have to buy it. I,ll start with the shifter coming out of the existing holes. Since I've done it twice before the holes just need a slight mod.
 

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