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Discussion Starter · #1 · (Edited)
I'm getting all the parts for my diesel swap, I have a appointment at a the local fritolay to look at some trucks he said there was a 4bt with a th400. It should be a repower, so if I get the truck I will have the convertion mounts and while I has looking at advance adapters for a np231 adapter I saw a chevy engine mounts for a v8 you think it would work with the convertion mounts in the P30?
http://72.20.96.178/commerce/ccpc10...eplacing-4-cyl-29-mount-kit-713090-713090.htm

Then moving onto axles I currently have d30/35 combo I know the 35 would grenade, so I found a ford 8.8 with 3:73s it should take the torque of the 4bt easily, but the front end is were I get stumped, I've been lookin for a D44 with 3:73 to swap in, I'm swaping in the 8.8 this weekend and next weekend/thankgiving break the engine. I was thinking I could weld some on some supports to the d30 to help it take the weight I remember someone but 4bt/nv4550 into a TJ with stock axle, so the d30 can take the weight but what about the torqe?

And since I would have to get heavier coils I saw these air bag to help support the front end.
http://www.jcwhitney.com/autoparts/.../p-2005927/N-111+600007276+4294966880/c-10108
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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D44's will take the weight and torque of the 4BT on the street. Off road the front D44 is the weak link. For snow and mud I think it would be fine, but not on rocks.
I would not recommend the D30/35 combo
 

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I would not recommend the D30/35 combo
I'll second that non-recommendation. The D30 has weak tubes, and a small R&P. A D44 will hold up well, with 35's or smaller and common sense. Anything more radical would need a D60/Rockwell/Unimog axle.
 

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Discussion Starter · #4 ·
I didn't think the d30 would work, so now its just the problem of finding a dana 44 with similar width, and 3:73 gears and a 5 on 4.5" pattern.
 
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3.73 gears are going to be too high for the best fuel economy. I have 3.73's and 35's on my zj, and it's revving pretty high even with 27% overdrive. Your stock axles would hold up fine to the power, those axles are fed more power from the factory with a 5.2 v8 in grand cherokees, and those last fine with a reasonable sized tires. If you're putting big tires on it and intend to abuse it offroad, then you'll need to upgrade. I've wheeled my 5000lb zj with a 4bt and a bone stock dana 30 and its ok. I do take it easy though, no jumps, but plenty of full throttle hill climbs and slow tight trails. Even with the extra weight of the engine, you're still within the rated capacity of the axle.


The chevy mounts in a p30 will not fit the chevy v8 conversion crap you're talking about. They are completely different. You will need to fabricate mounts. For springs, you can try some v8 grand cherokee springs. What transmission do you plan to use? This sounds like a crazy thanksgiving break project......good luck
 

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I didn't think the d30 would work, so now its just the problem of finding a dana 44 with similar width, and 3:73 gears and a 5 on 4.5" pattern.
You could get a late model pair of Rubicon axles if you wanted that bolt pattern or swtich to the old 5 on 5.5 (old jeep, ford pattern) and use some scout D44's. There's also wagoneer D44's but those are a bit wider and have the 6 lug, chevy style pattern
 

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Discussion Starter · #7 · (Edited)
I was planing to regear both axles to 3:07 or 2:73 after I got the engine in. Knowing me I probably wont get the engine in the jeep over break, get the rear axle in guaranteed though with the rear 8.8 in 3:73 I could still drive it around. As for mounts I though the P30 used a chevy v8? I saw Ggg had a nice looking front engine mount for his TJ 4bt swap. I'm using the Th400 thats coming with the 4BT I picked up a tail sleeve from a 4x4 version of the Th400 to attach the transfer case adapter.
 

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The Grand Wagoneer axles are actually about the same width as a TJ- about 60" wide. That 8.8 isn't going to hold up to a 4bt for very long. You would be better off running a 44, and if you want to keep your bolt pattern, get one from a downsize Cherokee from the late 80's. They are getting more rare, but can still be found, and fairly cheap. The 8.8s are prone to seal and bearing problems, among other things.

One more benefit of the Waggy axles- they usually come with 3.08 or 3.31 gears. Some come with 2.72, but I wouldn't go that far unless this was just a street vehicle, and economy was your only concern.

Jim
 

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Discussion Starter · #9 · (Edited)
From every thing I've read a 8.8 stock is stronger then most d44s I could later build the 8.8 almost upto ford 9" level
Also I can get a 2000 8.8 for $200 with 18k miles from my local yard.
If the d30 can hold the weight/torque of the 4bt I'll stick with it for now. And see about getting a rubicon D44 later.
 

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From every thing I've read a 8.8 stock is stronger then most d44s I could later build the 8.8 almost upto ford 9" level
Also I can get a 2000 8.8 for $200 with 18k miles from my local yard.
If the d30 can hold the weight/torque of the 4bt I'll stick with it for now. And see about getting a rubicon D44 later.
If you're going light duty, the 8.8 is the way to go. Free rear disc brakes if you find the right one. I would have went with an 8.8 had I had access to one, and saved myself some $$ on the rear disc setup for my D44. If you plan to do any offroading, consider the D30 for an immediate upgrade. You can beef the shafts & stubs, but the axle tubes are the weakest link.
 

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Discussion Starter · #11 ·
There would be offroading on the d30, but what I consider offroading mostly fire roads, and ill paved country roads. No rocks, not mud, nothing that would require 4w low.
 

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Discussion Starter · #13 ·
I got back from frito-lay and the truck with the 4BT/TH400 only has 135,000 on the engine/trans, and they want around $2500-3000 for the truck but there not selling it till they have more trucks to sell with it so atleast another few months till I get the engine. The mechanic also told me that frito-lay is going back to gas trucks after they sell there current diesels.

On the way back I stopped at another pick a part and found a d30 with 3.07s out of a 97 4banger with a 5speed the guy at the yard said he would to a strait trade for my front d30, the yard also had a ford 8.8 with 3.08 for $175but its a 1995 so its drum brakes :( I was taking to the guy about my swap and he said that I could get away with using the 3:07 in the front and the 3:08 in the rear and it wouldn't hurt anything that true?
 

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3.07 and 3.08 should work fine for you. I have 2.72 in front and 2.73 in rear they work fine together. I do mostly street driving and trail for it is limited to hauling my quads down the fire trail to find a good spot to load/unload them. On my swap, I'd planned on using the D30 for the front and a F8.8 for the rear. But, the gear ratio I wanted was not available for the D30. So, I had to go to a D44 from a Wagoneer. Otherwise, I would've felt completely comfortable with the D30 front axle. The F8.8 I'm using is from a 95 Ford Explorer with disc brakes. If your interested, Mountain Off-Road Ent. (MORE) sells a nice kit to swap the F8.8 into YJ's and TJ's.

Also, I don't know if you know about it. Dovebid.com holds commerical auctions for Frito-Lay about once per month. Just type 4bt into the search box.
 

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I was taking to the guy about my swap and he said that I could get away with using the 3:07 in the front and the 3:08 in the rear and it wouldn't hurt anything that true?
Possibly, but you're more prone to bind if you dont have the exact tooth count in each gearset. Even with the same gearset, most rigs will "bind" up in 4wd sometimes due to multiplication of the gear ratio (Low Range), tire size differences (due to normal wear), traction, etc.

Here's a few examples of close gear ratios but with different tooth counts

4.09:1 45 11 Dana 44
4.10:1 41 10 Dana 30 and others
4.11:1 37 9 Ford 9"
 

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I'm "that" guy from jeepkings.ca. about 600km city, and only 400km highway. That's with 4.88 gearing and the NV4500. I never use first gear on the street.

Right now I'm running D30/D35 on 35" MTR's, and babying it as much as I can until I pay some of the damages off.

I'm actually looking at different ratios to see what would work out best with me. 4.10's or maybe 3.73's... 3.54's out of cherokees would work for a while too.

Wanna find 60's, glad to find out about waggy axles.

I'll see where it all heads up.

-Scotty

www.overlanddiesel.com
 

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IMO I would replace the D30 front. Even the alloy D30 or D35 axles don't have the same torsional strength as stock D44 axle shafts. Plus you still have those really small u-joints, ball joints, and small (weak) DCX bolt pattern. I am not saying they will break immediately, just that the D44 will be much less likely to break.
I saw that you don't plan on any real hard off-roading so that will allow for a D44. But what is your max tire size you think you will run? I personally would not run a D44 with tires any larger that 35" but I plan on wheeling mine pretty hard and I am running 38.5" tires. Any larger tire than 35's will need a larger axle such as a D60, 609, 404, etc. I base this opinion on several factors, bearing sizes, brake size, ball joint or king pin size, axle housing strength, and steering component size. I realize these axles are not cheap (don't ask how much I have invested in my D60 front) but a front axle failure on the street is not my idea of fun. In reference to your rear axle choice I would definitely take an 8.8 over a D44 rear. I will be running a Sterling 10.25 rear, again tire size and my intended use dictate 1 ton axles.
I agree the AA SBC mounts will not work, I am trying to reuse my fluid mounts but it is pretty tight between the frame and block. BTW the engine mounts in my TJ are only temporary for fit up. If you have a GM style adapter with the right side starter you will almost certainly need to cut off the front right upper control arm frame mount to clear the starter, I did anyway. Another thing to watch out for is on the Jeep D44 axles, there were some with aluminum housings, stay away from them.
The TJ has a 60" wms dimension.
A 78-79 Bronco has a 65.25" wms. This is about as wide as you could go and use offset wheels to bring the tires back in close to where the stock tires were. The F250's with the H/D D44 front axle have a WMS of 68".
I hope this helps.
 

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On the way back I stopped at another pick a part and found a d30 with 3.07s out of a 97 4banger with a 5speed the guy at the yard said he would to a strait trade for my front d30, the yard also had a ford 8.8 with 3.08 for $175but its a 1995 so its drum brakes :( I was taking to the guy about my swap and he said that I could get away with using the 3:07 in the front and the 3:08 in the rear and it wouldn't hurt anything that true?
I think they are wrong about the gears, unless someone swapped them out. Jeeps were very standard about their gearing from the 80's through the 90's. This is what you got with each option:
4 cyl. 5 speed: 4.10
4.0, 5 speed: 3.07
4.0, auto (in XJs...not sure about YJs/TJs): 3.55

The only Jeep Dana 44s that had aluminum center sections were in some Grand Cherokees. Avoid those. The XJ 44 is quite strong.

DarylB, mixing gear ratios that are only .01 off is not going to affect anything. No binding, no other issues. Look at many factory vehicles, and you'll see them mix and match 4.10s with 4.11, 3.55 with 3.54, 3.07 with 3.08, etc. Two identical tires can be off more than that. Having a tire a couple pounds low on pressure will make more difference.

Jim
 

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Jeeps were very standard about their gearing from the 80's through the 90's. This is what you got with each option:
4 cyl. 5 speed: 4.10
4.0, 5 speed: 3.07
4.0, auto (in XJs...not sure about YJs/TJs): 3.55

Jim
In addition to the above, 1990 newer XJ's with the towing package were equipped with 3.73.

Mike
 

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I think they are wrong about the gears, unless someone swapped them out. Jeeps were very standard about their gearing from the 80's through the 90's. This is what you got with each option:
4 cyl. 5 speed: 4.10
4.0, 5 speed: 3.07
4.0, auto (in XJs...not sure about YJs/TJs): 3.55

The only Jeep Dana 44s that had aluminum center sections were in some Grand Cherokees. Avoid those. The XJ 44 is quite strong.

DarylB, mixing gear ratios that are only .01 off is not going to affect anything. No binding, no other issues. Look at many factory vehicles, and you'll see them mix and match 4.10s with 4.11, 3.55 with 3.54, 3.07 with 3.08, etc. Two identical tires can be off more than that. Having a tire a couple pounds low on pressure will make more difference.

Jim
My 97 TJ sport w/4.0L came with 3.73's.
 
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