NP231D HD hybrid for Jeeps

[John D]

The 241D/C come with 6 pinion planetary gears.

Huh?

It's been said that the NP231D HD that came in the V8 Rams came with wide chains and 6 pinion planetary gears, it was not true in my case, but I'll pass the info of what I'm doing along for the lucky bastard that does find one, or wants to go find one.

Edit: I see it now. I didn't see the difference 241/231. I'm retarded

 

[John D]

Serious, around here 231j/241c cases are $150+ on craigslist.

$150-$300 around here.

 

[hot_rod_hooligans]

I forgot that I didn't post this here:

After posting up over at Dodgeforum.com, I've found out apparently NONE of the 231D HDs came with 6 pinion planetary gears, just the wide chain. If you want a 6 pinion planetary, looks like the only options are to get one new from AA or JB Conversions, or get one out of a NP241.

 

[dirtweazle]

I have cracked apart THREE! post 95 241's form S-10 and they are all 4 gear.. These are a bit of a pain to remove but the feeling of the junk yard only charging me $20 for some chain, coupla gears and a big bearing still keeps me going back.. Getting quicker at it.. So Cal does not seem to be a Dodge truck capitol of any standard.. They are all probably all still on the road....:roflmao:

 

[EvanRigged]

I did this swap myself and if I could figure out how to add pics from my droid I would post them. I found a guy that was parting out a 91 S10 blazer and got the T-case for $50. The round metal badge on the case says 231C (not 231DC or any other crap) The chain is wider than the jeep chain by about 1/4 inch and the planetary cage has SIX GEARS IN IT.

 

[hot_rod_hooligans]

When I say 231 or 241 D/C/J "or any other crap", I mean Dodge/Chevy/Jeep but just don't feel like writing it all out, I figured people would understand. I'm building a post 95 case so anything earlier is of no use to me. Although the NP241C built in 95 that I cracked open at school, had 6 pinion planetary gears. I have no clue what it came out of.

 

[crash02]

Okay, sorry for the delay. I finally got around to ordering my parts. I got them off ebay from http://stores.ebay.com/powertrainpartsplus

The total cost for a wide chain with gears and a 6 planetary gearset shipped was $142. Everything is in perfect condition.

i just bought the same kit. now i just need to buy a sye before i install everything.i can hardly wait. thank you for the seller link and all the helpful info.

 

[Goose_XJ88]

Alright, going to dredge up an old thread since I want to do the same thing but on a 21 spline 231. Everything that Ive read seems to be for a 23 spline. The pirate thread seems like the guy figured out for a 21 spline but didnt have the years listed of what he pulled parts from. So does anyone know if this swap is possible with keeping the 21 spline input or is that something that gets replaced in the HD chain swap? Also if I have to gut two TC's there was also mention of the 6-gear planetary having a different cut gears..any input on that? Just trying to make one trip to the JY snd mske this swap as easy as possible since im not the most mech inclined..haha.
http://pgh-offroad.com/forum/showthread.php?6070-NP231-Tech-Thread
http://www.pirate4x4.com/forum/jeep-hardcore-tech/351184-np-231j-upgrades.html
http://www.naxja.org/forum/showthread.php?t=1044187

 

[hot_rod_hooligans]

Educated guess says that 21 spline will not effect the wide chain, only the 6 pinion planetary. For the planetary gears you'll need to get it from a pre-96 Chevy or Dodge.

 

[MoparManiac]

Why not just swap a 241 in after all this effort? You get a much beefier case as a bonus too.

I've never mocked one up but I can't imagine the clocking is all that different.

 

[hot_rod_hooligans]

Don't know that anyone makes a 21 spline input for a 241?

 

[kastein]

If the planetary gearset is compatible (94.0 vs 94.5 is the split on NP cases, iirc...) with the inputs from both jeep and dodge so you can swap the planetary, I see no reason you couldn't swap the input gear from a 231 into a 241.

Also, it looks to me like that first 231D you got is a 231D, not a 231DHD. Tag says 231D.

 

[crash02]

Educated guess says that 21 spline will not effect the wide chain, only the 6 pinion planetary. For the planetary gears you'll need to get it from a pre-96 Chevy or Dodge.

X2
Yes make sure that the planetary you get has squared/rounded gears. when I bought the kit (chain, sprockets, and 6 Pinion planetary) I started I had an 89 231 and didn't find out about the Pinion gear cut differences until after my case was completely apart .I noticed the new planetary pinions were sharper looking, emailed the guy off ebay and then sent off the planetary to exchange for the older gear cut. Everything went back together like stock.

Sprockets don't make a difference on years.

 

[Goose_XJ88]

Ok, so if I understand correctly, a pre 96 dodge or chevy 231HD should have the wide chain parts and the correct gear pitch on the 6 gear plannetary for a 21 spline input 231j?

 

[MoparManiac]

Don't know that anyone makes a 21 spline input for a 241?

If the planetary gearset is compatible (94.0 vs 94.5 is the split on NP cases, iirc...) with the inputs from both jeep and dodge so you can swap the planetary, I see no reason you couldn't swap the input gear from a 231 into a 241.

Also, it looks to me like that first 231D you got is a 231D, not a 231DHD. Tag says 231D.

What Ken said.

I swapped a pre 94 23-spline input from a Jeep 231 into a pre 94 Chevy 241 that had a 6 pinion planetary so I could mate it up to a Dodge NV4500 (23 spline output) as my rangebox for the doubler.

You can even swap wide bearing vs narrow bearing inputs as long as you use the correct bearing with it.

The other bonus is that the 241 has 32 spline outputs front and rear.

Still working great a year later.

Chevy 241 from a K1500

Chevy 241 on left Jeep 231 on right

3 pinion vs 6 pinion planetary

Chevy 27 spline wide bearing input from 241 vs Jeep 23 spline narrow bearing input from 231

Narrow bearing vs wide bearing

Range fork differences. 231 in back 241 up front.

 

[kastein]

Actually, any chance you have the cam thing that drives the forks hanging around from that rotten scrap case I gave you for testing? I've got some ideas I want to try out. If you scrapped it already or have a use for that rusty junk I'll pay 5 bucks for one at the junkyard :laugh3:

 

[MoparManiac]

Pretty sure I still have it.

Shoot me a text tonight or something.

 

[Built2Flex]

Next step is a JB Conversions S/S SYE

Indeed. I sport the JB short shaft. Love it!