2004 Cummins 4BT Swap - 5-Speed Tremec 4050 - NP 205

FYI the bead blasting cabinet is HF with all the Tacoma Company retrofitted upgrades (highly Recommend) all the mods can be found at Rays Garage on You Tube. Turned a Chinese Blast Cabinet into a top end piece of equipment

I am sending the yokes out to a buddy of mine to put in his lathe and polish the seal surfaces they are not terrible but could be better. Believe I am going to skip the twin stick and just stay with the conventional 4L N 2H 4H I mean seriously how bad can the Parking lot curbs at the mall really be
 
  • Like
Reactions: lBasket
Got some Transfer Case Parts bead blasted, primed and painted

IMG_1100.jpg


IMG_1101.jpg


IMG_1107.jpg
 
  • Like
Reactions: NashvilleTJ, Rickyd and lBasket
Started chasing all the threads on the T-Case FYI 3/8 x 16 Tap and 5/16 x 18 Tap a bottom tap is required as some of the holes are blind. There are also a couple of hole with a NPT ( National Pipe Thread ) I will need to order a NPT Tap. Taps come in three styles: Taper Style: Starts the thread square with the workpiece. Plug Style: Generally used in thru holes. Bottom Style: Generate the thread to the bottom of the hole.

Taps.png

I cannot site the exact source but a mechanical industry study found that most mechanical failures are caused by the failure of the Fastene ( the bolt, the nut or the threads) these causes can be improper torquing, Fatigued metal and stretching. Its overlooking the little details that leave you broke down on the side of the road or the trail or worse.
 
  • Like
Reactions: Wildman, Woodrow and Rickyd
I don’t understand why you want this transmission. It’s really tall. I can only imagine it hanging down lower than the TCase skid. It’s crazy heavy. What are you trying to accomplish with the build?
 
JMT said:
I don’t understand why you want this transmission. It’s really tall. I can only imagine it hanging down lower than the TCase skid. It’s crazy heavy. What are you trying to accomplish with the build?
Click to expand...

Look at the rest of the drivetrain. He needs a heavy duty trans behind that cummins. Nothing about this setup is small or lightweight.

A guy i know has a very similar setup in an fj40. I love that its loud, smokes and vibrates like crazy at idle.
 
  • Like
Reactions: Wildman
JMT said:
I don’t understand why you want this transmission. It’s really tall. I can only imagine it hanging down lower than the TCase skid. It’s crazy heavy. What are you trying to accomplish with the build?
Click to expand...

Because it can handle the TQ from the Cummins, its new and has a nice low 1st gear. My idea was to put in drivetrain that is bullet proof these engines have been used everything from Farm Tractors, Heavy Equipment, Gensets, Ships to Trucks. there are zero engine electronics the only electrical part of the engine system is a fuel shut off solenoid, the starter and the alternator they are pretty much EMP proof no engine codes, no engine computer sensors. no ignition system. My research also shows that the 4 bt converted wrangler gets somewhere in the 25 MPG range and that is probably a little conservative. so if I run a 30 gal tank and 2 five gal jerry cans I'd have a range of 1000 miles +/-. These cummins 4 BTs are designed to run all day in just about any environment from the artic to the desert. There are downsides it is expensive as fuck to do it right but is still cheaper than a new jeep and some used jeeps, the Cummins is a couple hundred pounds heavier than a 4.0 jeep engine, plus the the extra weight of the 5 SPD if any and the NP 205 Transfer Case which is about 150 lbs fully dressed and is also the best Transfer Case ever put in any factory 4wd, they can be noisy but all jeeps are noisy anyway,
your question (What are you trying to accomplish with the build?) hell why do any of us do anything to our Jeeps because its cool

Cool shit ain't cheap and cheap shit Ain't cool
 
Last edited:
  • Like
Reactions: Rickyd, Wildman and Shank
JMT said:
I don’t understand why you want this transmission. It’s really tall. I can only imagine it hanging down lower than the TCase skid. It’s crazy heavy. What are you trying to accomplish with the build?
Click to expand...

There are no real good alternatives. An AX15 isn't suited for this and a NV4500 shifts like a dump truck.
 
  • Like
Reactions: Wildman and Gunnersmate
Gunnersmate said:
Because it can handle the TQ from the Cummins, its new and has a nice low 1st gear. My idea was to put in drivetrain that is bullet proof these engines have been used everything from Farm Tractors, Heavy Equipment, Gensets, Ships to Trucks. there are zero engine electronics the only electrical part of the engine system is a fuel shut off solenoid, the starter and the alternator they are pretty much EMP proof no engine codes, no engine computer sensors. no ignition system. My research also shows that the 4 bt converted wrangler gets somewhere in the 25 MPG range and that is probably a little conservative. so if I run a 30 gal tank and 2 five gal jerry cans I'd have a range of 1000 miles +/-. These cummins 4 BTs are designed to run all day in just about any environment from the artic to the desert. There are downsides it is expensive as fuck to do it right but is still cheaper than a new jeep and some used jeeps, the Cummins is a couple hundred pounds heavier than a 4.0 jeep engine, plus the the extra weight of the 5 SPD if any and the NP 205 Transfer Case which is about 150 lbs fully dressed and is also the best Transfer Case ever put in any factory 4wd, they can be noisy but all jeeps are noisy anyway,
your question (What are you trying to accomplish with the build?) hell why do any of us do anything to our Jeeps because its cool

Cool shit ain't cheap and cheap shit Ain't cool
Click to expand...

So, the substance of the purpose is to survive an EMP and post-EMP world?
 
  • Haha
Reactions: NashvilleTJ
Shank said:
Or somewhat of an example of reliability. Why is his motivation to build it relevant?
Click to expand...

Just trying to understand why someone would want to do it. Unless money is no object I assume people don’t just do something because it can be done, but to meet some goal or purpose like go through swamps, look cool, crawl rocks, fly through desert, et al.

I read his other thread and didn’t find the answer. Just got the Cummins and started to work on it. Didn’t seem practical to me, but if you’re trying to survive an EMP it makes some sense.
 
  • Like
Reactions: Shank
Gunnersmate said:
No the objective is not some post EMP proof vehicle. I grew up on a farm and I like simple, reliable and easy to work on when needed.
Click to expand...

There was nothing to do. Jeep was working fine. Simplest thing to do was nothing. I thought these rigs were already simple, reliable, and easy to work on. To each his own. Just didn’t make sense to me.
 
  • Like
Reactions: tnjeepguy
JMT said:
There was nothing to do. Jeep was working fine. Simplest thing to do was nothing. I thought these rigs were already simple, reliable, and easy to work on. To each his own. Just didn’t make sense to me.
Click to expand...

Why do an LS Swap or a hemi Swap or put on a lift kit, HD bumpers and Winches, lights swap in Dana 60's hell why not leave the shitty tires on that it came with from the factory
 
  • Like
Reactions: MichaelGH
This is oddly argumentative. If I want to do something I just would. Guessing he wanted to.
 
I dig it. The injection pump looks like the Bosch units that were on the MB 617 motors. I had one of those and ran all kinds of "fuel" thru it; ATF, engine oil, fryer oil, etc. Can you do that with the 4bt?
 
  • Like
Reactions: ColoJeep
JMT said:
Just trying to understand why someone would want to do it. Unless money is no object I assume people don’t just do something because it can be done, but to meet some goal or purpose like go through swamps, look cool, crawl rocks, fly through desert, et al.

I read his other thread and didn’t find the answer. Just got the Cummins and started to work on it. Didn’t seem practical to me, but if you’re trying to survive an EMP it makes some sense.
Click to expand...

The 4BT swap has been done on CJ/YJ/TJ rigs for years now and your options for a transmission were a Turbo 400, 700R44 or for a manual most times it was a truck 4 speed. The 4050 is a better choice for those wanting a manual.
 
  • Like
Reactions: MichaelGH and Gunnersmate
Top Bottom
Back