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I've decided to do a Cummin's conversion

Things are a little slow with the cleanup from the hurricane taking a front seat to everything else. As I'm not a young 'rooster' anymore and have disabilities I'll eventually get it all done 'slow but sure' in the tear down mode now.

So far I have the 12 valve, destroked 12v to GM adapter w/billet flexplate, 6.0 powerstroke starter, manual t-case floor shifter w/trim, and gmcuminsconversions.com motor mount brackets that use the 1st gen dodge ram cummins mounts.

Still a GMT400 gasser throttle pedal-cable, Quick4 trans controller, low stall torque converter, FERMS NP241c & lengthened front driveshaft to the IFS diff for now.

After I get all the conversion bugs worked out and do some shake down runs I'll do the SAS conversion.
 
THEFERMANATOR said:
Fleet pride in Tampa can retube your old shaft for you normally for under $150. I wouldnt reccomend shortening an oem shaft as GM used thin steel and packed them with cardboard for dampening. Are you trying to stick with your push button case still? Wasn't sure if it would even shift without ecm input for speed and gear from the j1850 data bus.
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FERM, which Fleet Pride the are a few different ones?
 
Fleet pride on 40th street in Tampa does them as well as there St Pete location. I was recently informed that the Tampa location is supposed to be doing aluminum shafts now. I HIGHLY reccomend an aluminum shaft in the suburban. I couldn't believe how much it smoothed out my driveline in mine swapping over. I always had some unusual harminics in mine with the 6.5l and duramax engine, but the aluminum shaft took them all away. I used precision in Clearwater for my last shaft because I hadnt heard about fleet pride doing aluminum, and I had already twisted 1 3.5" .086 wall steel shaft, so I wadn't going steel again.
 
Do you plan on doing anything with the trans while it's out? I'd at least find a billet cover converter with a 1300-1500 stall to put in it and do the transgo hd2 kit to increase converter flow/coupling. And put a 3k gsk in your cummins to get some rpm's out of it(and don't forget the kdp while you're at it).
 
THEFERMANATOR said:
Do you plan on doing anything with the trans while it's out? I'd at least find a billet cover converter with a 1300-1500 stall to put in it and do the transgo hd2 kit to increase converter flow/coupling. And put a 3k gsk in your cummins to get some rpm's out of it(and don't forget the kdp while you're at it).
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The trans is already over built & has the HD-2 kit, I'll have Florida Torque Converter south of you build me a billet 1.0k/1.2k rpm low stall converter for $499 I suspect it will hit 1.3k/1.4k at stall as stock this 12v has +- 420 ft lbs tq @ 1.5k rpms.
I have a P pump and will tweaking that too as the killer dowel pin goes I did that many years ago on this 12v.
I am kicking myself in the ___ as I recently switched out 3.42 gear-sets for 4.10's ans yes I sick enough to go back to the 3.24's too........
OH, FERM I received the floor shifter, rod and trim cover so I'll be seeing you in the not too distant future too looking forward to meeting you!
 
THEFERMANATOR said:
Yep, you're gonna want 3.42 or 3.73 with a CUMMINS. 4.10's will run out of steam WAY to early with a 12 valve. Let me know when, were in the heart of fishin season, and I'm trying to get out and get some fishin time in.
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I know about the gears as the Cummins is in an old low mileage ram 3500 that has 4.10 gear set.
 
Im thinking about selling the 3.42s I have. I put them in my truck before the camper. Now I have 4.11 back in it but also a US Shift overdrive, so don't need the 3.42s now. They have maybe 6000 miles max on them.
Let me know.
 
The motor mount bracket kit is from gmcuminsconversions.com is of high quality excellent instructions and over the phone help is well 'excellent too.' The kit allows mounting the 12 valve on the existing GMT400 motor mount chassis pads and comes with front differential clearance bolts uses 1st gen cummins ram mounts.

Aside from moving the 12 valve back (mine will be 2.25") I get to use the factory Cummins cooling fan/clutch. The firewall needs to be recessed too for diesel to trans adapter clearence and for access to the bell housing bolts.

Picked up heavy walled drive shaft shortened 2.25".

The 12 valve to Chevy/GMC adapter, 2k foot lb flexplate is from Destroked, starter is FORD 6.0 diesel.

Finally will get the 6.5 long block out this week end.

Picture soon to follow.....
 
As the transmission goes my objective is the 47rh w/241 DHD 'like pictured' it's controller free w/2 wires one for the OD and the other for LU if perhaps I lose one or both I can still drive but with only 3 gears w/o damaging anything. 'Notice the GM styled trans mount.' I have a low 1.0/1.2 k stall converter on my 47rh and can say it's a dog from a stop but there is no slippage to get things rolling as with a higher stall speed.

fc_drivetrain_47rh_np241dhd_assembled.jpg
 
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