Cummins 5.9 guys, you happy with your swap?

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Mudbull
Posts: 131
Joined: Mon Mar 25, 2013 8:07 pm
Location: Lakeland, FL

Re: Cummins 5.9 guys, you happy with your swap?

Post by Mudbull »

For what its worth they don't care about anything in FL. everything except the sheet metal is dodge, but it is still registered as a 68 Gladiator (I did change the color from black to white, that's all)...
68' Gladiator
p-pumped Cummins
6spd, D60 Front, D80 Rear

Bostonbob
Posts: 262
Joined: Tue Mar 26, 2013 4:31 am
Location: Conifer CO

Re: Cummins 5.9 guys, you happy with your swap?

Post by Bostonbob »

the swap isn't for everyone [ I've planned two of them , and something always gets in the way ] got another planned , if your thinking about one . find the donor and run it for a year , if you still like it the host vehicle you might love it something cool after you stop putting gas in your rig , remember to plug it in , diesel additives , aren't for looks and getting used to buying more expensive stuff . 3 gallon oil changes $ 15 oil filter $20 fuel filter . 2 batteries baf [ big ass air filters ] and real tires [ load range E ] no s 10 parts will be used my 2 cents worth [ just did a $99.98 oil change on the CTD ]

lil jeep mec
Posts: 94
Joined: Fri Nov 09, 2012 11:17 pm
Location: Kennewick, WA

Re: Cummins 5.9 guys, you happy with your swap?

Post by lil jeep mec »

you have to know where to get parts, dodge using a ball joint d60 is a horrible idea... i would only use king pin dana 60's along side of leaf springs.. i have a 1993 w250 that is my dd and my j10 being a toy in the process.. it will also get a 12v in the near future, along with a d60 and eventually 5 ton rockwells but that will be quite a few years. anyways i average around 21mpg mixed driving and im pushing just over 300rwhp.

my 2 cents i wouldnt do anything besides a diesel swap
78 j10 4bbl 360 on 35's
360, t18, d20, d44, 4.09's
plan on...
-SOA
-40's-77's
-Axletech 4000's 4 wheel steer
-not cutting the flares
-twin stick
-4 link front and rear

MJMadness
Posts: 101
Joined: Wed Aug 06, 2014 1:46 pm

Re: Cummins 5.9 guys, you happy with your swap?

Post by MJMadness »

lil jeep mec wrote:you have to know where to get parts, dodge using a ball joint d60 is a horrible idea... i would only use king pin dana 60's along side of leaf springs..
I've owned two (still own one) Dodge trucks with the BJ unitized hub front axles. They are a bad idea, but I wouldn't go as far as to say a horrible idea. Wheel bearings are the main problem, life is anything between 30K miles to 120K miles, with no real rhyme or reason to failure. That's assuming stockish sized tires and mixed town/highway/gravel usage. The balljoints are normally safe to do about 120K miles, or a bit more... Otherwise they hold up fine, unless you use the stock driveshaft yoke (1310 u-joint, yeah, there's a bad idea).

Also, the Dodge coil suspension is fine, if you're into that type of thing. I'm not saying that it would make any sense to try to adapt it to another frame, but it does work fine. I prefer it over front leaf springs, although Dodge made the control arms a little too short.

I will say, if you're going to go out and buy a 1-ton axle specifically for your diesel swap, then yes, buy a kingpin axle.

cone
Posts: 49
Joined: Tue Mar 26, 2013 4:59 am

Re: Cummins 5.9 guys, you happy with your swap?

Post by cone »

I did the 6bt swap into my 87 j20 a couple of years ago and it works great. I used the motor, nv4500 and np241hd out of a rusted out 94 dodge. All I did was box the j20 frame. The j20 axles work just fine, you don't have to swap them out. I just got some heavier springs from alcan springs. I have pulled up to 10,000 lbs with it and get over 20mpg on the highway.

jtwthaxj
Posts: 35
Joined: Mon Oct 20, 2014 6:38 pm

Re: Cummins 5.9 guys, you happy with your swap?

Post by jtwthaxj »

I am in the parts collecting stage of one of these builds, thus far I have :

1988 Grand Wagoneer
1996 12v 6bt

Working on getting Dana 60 from a f250 03-04 with the manual hubs, sterling 10.5 rear (both with have spring over axle perches, disc brakes, and 3.73 gears should keep cruising speed rpms to about 1900). Looking for the manual transfer case and the 5 spd auto trans (5r110).

Hoping with all of this to run 37s to 39s and keep mpg to 20-25mpg, any thoughts or suggestions? Any one try this combo yet?

Jeff

Bostonbob
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Joined: Tue Mar 26, 2013 4:31 am
Location: Conifer CO

Re: Cummins 5.9 guys, you happy with your swap?

Post by Bostonbob »

25 mpgs is only going to happen going down hill [ the longer the hill the better ] a jeep is not a wind tunnel star , I'm building mine for a solid 20 mpgs and on 33s , and I'll be bragging big time when it gets 22 my 2cts
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Mudbull
Posts: 131
Joined: Mon Mar 25, 2013 8:07 pm
Location: Lakeland, FL

Re: Cummins 5.9 guys, you happy with your swap?

Post by Mudbull »

Bostonbob wrote:25 mpgs is only going to happen going down hill [ the longer the hill the better ] a jeep is not a wind tunnel star , I'm building mine for a solid 20 mpgs and on 33s , and I'll be bragging big time when it gets 22 my 2cts
I drove my donor Dodge Ram for 12000mi before dismantling it, I logged my mileage the whole time. it was a fair bit of hwy miles, but some decent stop and go's too. In that period I logged two 25mpg runs, hand calculated over 350mi long each trip, fill up at the same pump and same # of 'clicks'. The truck was 7000lbs and had 3.54 gears, manual trans, and 31" tires. With that being said the avg over 12000 was just over 20mpg.
68' Gladiator
p-pumped Cummins
6spd, D60 Front, D80 Rear

jays jeep
Posts: 7
Joined: Mon Feb 24, 2014 1:59 pm

Re: Cummins 5.9 guys, you happy with your swap?

Post by jays jeep »

Mudbull wrote:
Bostonbob wrote:25 mpgs is only going to happen going down hill [ the longer the hill the better ] a jeep is not a wind tunnel star , I'm building mine for a solid 20 mpgs and on 33s , and I'll be bragging big time when it gets 22 my 2cts
I drove my donor Dodge Ram for 12000mi before dismantling it, I logged my mileage the whole time. it was a fair bit of hwy miles, but some decent stop and go's too. In that period I logged two 25mpg runs, hand calculated over 350mi long each trip, fill up at the same pump and same # of 'clicks'. The truck was 7000lbs and had 3.54 gears, manual trans, and 31" tires. With that being said the avg over 12000 was just over 20mpg.

I am planning a similar build up. What year Ram was it that you used. I agree about buying a donor vehicle and driving it for 10,000 plus miles before doing a major project like this. The only diesel I have owned is a 2010 Ram dually and after replacing the 2nd head gasket on the 6.7 I sold it. I know I want the 5.9 for the milage and no emission crap. But what exact years are better for the conversion?
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Mudbull
Posts: 131
Joined: Mon Mar 25, 2013 8:07 pm
Location: Lakeland, FL

Re: Cummins 5.9 guys, you happy with your swap?

Post by Mudbull »

Coincidentally I'm (hopefully) just wrapping up a head gasket replacement (320,000mi on stock gasket if original owner told the truth). My truck was a 1996 ram dually. The 94-98 have the 'p-pump' injection pumps and no electronics. I ditched the fuel shutoff solenoid b/c it was in the way of my brake booster, and I live in FL so I removed the grid heater and fuel heater. All I have is a pull cable to shut fuel off; the only electrical I need is 12v for the starter. If you weren't aware though, the 94-98 automatics are quite weak, my truck was on its 3rd when it blew and i swapped to an NV5600.
68' Gladiator
p-pumped Cummins
6spd, D60 Front, D80 Rear

jtwthaxj
Posts: 35
Joined: Mon Oct 20, 2014 6:38 pm

Re: Cummins 5.9 guys, you happy with your swap?

Post by jtwthaxj »

So parts list so far

1988 GW
1996 Dodge Cummins 6BT with p pump and 180hp injectors
2006 Ford 5r110
2006 NP 271 T-case
2006 Dana 60 with manual hubs
2006 Sterling 10.5
2006 Ford Hydroboost master cylinder
2006 Ford Intercooler

Any suggestions you guys can make for parts other than adapter, flex plate, and controller?

I know most guys are running 3 and 4 spd autos and getting high teens and low twenties, hoping I can one up this with the 5 speed with overdrive.

thanks,

J
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Mudbull
Posts: 131
Joined: Mon Mar 25, 2013 8:07 pm
Location: Lakeland, FL

Re: Cummins 5.9 guys, you happy with your swap?

Post by Mudbull »

I had a dying 47RE in my donor truck for a couple thousand miles, I averaged 5+mpg worse with the auto than my NV5600 (everything else being the same). Im sure the slippage and wear internally contributed to some of this difference too. Manuals seem to be getting harder and harder to come by though
68' Gladiator
p-pumped Cummins
6spd, D60 Front, D80 Rear
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