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Discussion Starter · #1 ·
Hi guys

I'm about to start my yj diesel swap, I've been researching steady for a few weeks and I've come up with some questions that I just can't seem to answer.

1.) How do I tackle the fuel system? (Can I use the stock tank?, what kind of pump do I need? And with fuel lines should I use (size?))
2.) Drive shafts? I know I need a stronger rear shaft and I'm assuming I'll need a front as well (where can I get them?)
3.) What transfer case would you recommend?

I've probably forgot something but I'll start with these.

Thanks guys!
 

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first i need to know what your goals are? high way milage, on and off road or just a trail rig?
fuel tank is fine just clean it. no need for a in tank pump just have to have a pick up in the tank and you can use the stock fuel lines. the dana 35 and 30 are time bombs. for high way might make it a little while with a stodck engine with no mods. on and off road 44s would be better. for a trail rig dana 60s or ford 9''. for the cheapest way it to run full with one tones for a trail rig. thans fer case i would recomend an atlas twin stick. most people try to build the smaller tranfercases and just up waisting money you will only save your self a couple hundred dollars in the long run and the torque rips them appart. i bought a yj with a rotary pump 4bt nv4500 and a 241dhd with stock rears. the rear lasted 5 miles on a slight moded ve pump. i am now installing a p-pump engine with a hamilton cam, 4000 gov springs. and building a set of hx30w hx35/40 compounds. with bigger injectors. backed by a nv4500 to an attlas 4.3 to 1 ratio. going to dana 60s with 4.10s. do your reaserch and do it once.

Otto
 

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Discussion Starter · #3 ·
The goal for this rig is a daily driver, with some light off road use here and there nothing crazy. I am planning on Dana 44's or 60's I'd prefer not to go full width, but beggers can't be choosers. I want to do it right but I'm on a high school part time job kinda budget, so I'm tryubg to spend the money where it counts.

Thanks you!
 

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Front D44 off a narrow track 80 thru 84 Jeep Wagoneer (driver side drop) or FSJ Cherokee and rear narrow track D44 off 74 thru 79 Wagoneer or Cherokee would work. Not as wide as full size axles from the big 3. But, they are 6 lug, 6x5.5 like the older Chevy trucks. I rebuilt and locked a pair of D44s and installed on one of my old CJs. They weren't too wide and tough enough for a light CJ on the trails.
 

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Discussion Starter · #5 ·
I've been looking for wagoneers but so far no luck, I'll probably just go full size and later down the road get some built to length, I still can't find a good place for custom drive shafts either.

Thanks guys!
 

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I put a 4BT and T19 into my 1983 CJ7; I used a Novak adapter to mate the stock Dana 300 to the T19. The transfer case bolted to the native mounting point, which put the back of the 4BT about 2" ahead of the firewall. The T19 shifter fell directly under the shifter boot, and the transfer case shifters came out in the stock location. The front pulleys ended up two inches behind the front axle.

Because the transfer case remained in the stock spot, the driveshaft lengths were unaffected.

You will destroy your 30 and 35 axles, so start gathering those parts, too.
 

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Discussion Starter · #7 ·
Thanks for all the feed back guys its a huge help!, I was looking at a t19 but a friend of mine e has a nv4500 that he's selling to me so I already got that covered, so the only questions I have left are custom axles and power steering, I can't find any good info on either of those

Thanks again guys!!
 

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I used the jeep AX15 trans, and NP231 with SYE kit. I used the stock location to mount trans and transfer case, so the driveshafts didn't change. I did upgrade the driveshafts to some custom 1330 CV style ones, and i used full width bronco axles. If you find wheels with the right offset, the tires won't stick out very far (beyond what they would if you went with aftermarket wheels on stock axles).

I converted to hydroboost brakes, and used the PS pump that came on the 4bt to power that and the power steering box in series. You can use the factory jeep PS box, but I did the durango upgrade.. It's cheap, and a bit of peace of mind if you're running larger tires.

I've got an NV4500 2wd that has to be converted, and plan on swapping it in with an NP205 once I get the funds, but in the meantime the jeep trans is holding up great! It's been a year and a half, no issues other than broken motor mounts and torn transmission mounts. Be sure to brace everything well...
 

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I just found an old pic of my full width 9" with dodge 1500 wheels, on 33" tires. With the factory flares they don't stick out too much beyond what they would on D35's with aftermarket offset wheels. I didn't think it was worth cutting down a full axle to gain a few inches when it looked fine the way it was!
 

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Discussion Starter · #10 ·
Thanks again for all the help guys, what I think I've gathered is that I can use stock yj fuel tank and lines, stock steering box, stock drive shaft? Just stronger joints?, I'd love to use an atles tcase but that's a little rich for my part timer blood so I'm going to use a Dana 300 if I can get one.. Seems like I'm going with full width axles so I'm going all out with some 8 lugs!, also I've seen a lot of people selling motor mounts and recommendations on those??
 

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You can re-use the fuel lines, I re-ran new ones since I had the body off. You have to gut the fuel pump from the tank, and run a pickup tube to the bottom where you're sure you won't get any air. I had stock 1310 joints on my truck for a while and they held up as long as the drive angle was good, the weak link will definitely be stock axles.

Be careful of motor mounts.. I made my own and re-used the liquid filled cummins mounts as I was looking for less vibration. The truck still rattles a bit, but I've read about plenty of disappointment in the solid rubber mounts sold by pre-fab companies. Some guys use the 6bt 45* mounts with no complaints, but I'm happy with the ones I made. Be sure to use the mid-mounts instead of the front location, as it will put less stress on your bellhousing area. The little AX15 is a reasonably strong transmission, but it still has it's limits. Best to play it safe and take as much stress off of it as possible..
 

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Discussion Starter · #13 ·
Have you considered a B3.3 instead of the 4bt? Same power with less axle shredding torque.
I did but they are harder to find in my area then a 4bt and when you do find one its two times as expensive... But yeah I did check them out. Once again guys thanks this is the best forum I've ever asked stupid questions on. I was pretty intimidated by this whole thing but now that I know there's a group of poliet people willing to help it doesn't look so hard *knocks on wood*
 
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