What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

73 K20....crossmember time

Overview Gallery Discussion
241s survive behind high horsepower rigs. And usually if they fail its a chain related issue. You only use the planetary section of it. It does require some grinding and cutting, bit of welding, but its superior. Yes 4 speeds instead of 3, and as far as strength, I would say not counting direct impacts or failures resulting from improper mounting, the strength would be similar.
 
If you don't want to go 203/205 then I would buy a kit from NWF and run the guts from the 241 in an underdrive in front of a 205. It's about the same cost as a 203/205 doubler kit but you get a brand new stronger than stock housing for the 241 guts to make the doubler. The 241/205 would be way better for an auto equipped rig or for something that had numerically lower gearing in the axles. As some have said, if you go sm465/241 then you are already getting a pretty low gear that is better than a th350/203/205.

For comparison:

th350/203/205 = 14.64
sm465/241 = 17.82
th350/241/205 = 19.91
sm465/203/205 = 26.20
sm465/241/205 = 35.63

Personally, I went with sm465/203/205. I paid $400 for my 32 spline hydro sm465 and since I bought the package used I only paid $1,100 for my 32 spline in/out 203/205 complete with triple sticks. With 4.56 gears my lowest crawl ratio is roughly 120:1 disregarding tire size. If I had gone sm465/241/205 that would be roughly 163:1 crawl ratio!

Here is a pic and link for the NWF eco box if you want to go that route.

thumbnail.asp


http://www.northwestfab.com/NWF-Eco-Box-Billet-Planetary-Doubler-Case_p_2403.html
 
Yeah, I would just flip what you bought.

I have an SM465/NP203/NP205. I wish I had an NP241/NP205 instead.

Martin
 
82355 said:
I have an SM465/NP203/NP205. I wish I had an NP241/NP205 instead.

Martin
Click to expand...

Is that because you want an even lower double low or because you want to try and run in single low at 2.72?

I think most doubler manufacturer's say not to run the front case in low and the main case in high. It is supposedly harder on the intermediate shaft.
 
Its only hard on the 203-205 style. The shaft the 241 uses to connect to the 205 is completely different, and its huge. Google it, it will surprise you. You can find side by side pictures of them both, and the difference is significant. And that is its main advantage, it allows you to use the higher low of the 205 for one thing, and the much better 241 low for your other stuff, and not be stuck with the exact same gearing of the 203. Plus, the failure rate is very minimal, you will explode a 30 spline front output on your 203 before you break an intermediate shaft.
 
454Sub said:
Its only hard on the 203-205 style. The shaft the 241 uses to connect to the 205 is completely different, and its huge. Google it, it will surprise you. You can find side by side pictures of them both, and the difference is significant. And that is its main advantage, it allows you to use the higher low of the 205 for one thing, and the much better 241 low for your other stuff, and not be stuck with the exact same gearing of the 203. Plus, the failure rate is very minimal, you will explode a 30 spline front output on your 203 before you break an intermediate shaft.
Click to expand...

Good to know. Too late to change plans for my build but I guess my oldest son's build will be getting one of those 10 year's from now when he's ready to drive :waytogo:
 
I made a doubler thread just as a heads up. I want to get more traffic on the 203 vs 241.

Id like to try to keep the 205. it really only needs an input shaft I think. I wouldnt say the 205 is rare out here but transfer cases dont come up a whole lot on Craigslist around here.

Theres parts of the 241 I like but other parts I dont like. Im not sure how people are sealing the massive area you cut away/ open. I know theyre using rtv to the adapter but how about the rest?

I honestly don't know that id want a deeper low from what ive seen 5.38, 465, 203/205 run at. It's pretty low and really the perfect speed for rock crawling. At some point going too low breaks stuff but maybe its a non issue.
 
I really loved my th400/203/205 4.56 42s combo. Lots of control and strength. I'm going with the same set up on my current build (38s though).
 
brokenparts said:
I really loved my th400/203/205 4.56 42s combo. Lots of control and strength. I'm going with the same set up on my current build (38s though).
Click to expand...


Yeah I mean I run 40s and I plan on doing 5.38 gears. ive seen a bronco with a 203 205 and a manual and it was pretty damn slow even with 4.56 gears....maybe 2 or 3 mph in double low. bmxbryant9s truck idled up stuff...even with 42s. It would be painful to go any slower lol
 
wetoolowdingbangow said:
Theres parts of the 241 I like but other parts I dont like. Im not sure how people are sealing the massive area you cut away/ open. I know theyre using rtv to the adapter but how about the rest?
Click to expand...

You don't have to use the NP241 case, most of the doubler kits are NP241 reduction carriers.

Martin
 
wetoolowdingbangow said:
Id like to try to keep the 205. it really only needs an input shaft I think. I wouldnt say the 205 is rare out here but transfer cases dont come up a whole lot on Craigslist around here.
Click to expand...

You would need to swap out that 10 spline input for a 32 and machine the NP205 for the bigger bearing. I believe ORD sells a kit for this ($190)

32 spline 205's are a bitch to find, for a decent price anyway.
 
skunked said:
You would need to swap out that 10 spline input for a 32 and machine the NP205 for the bigger bearing. I believe ORD sells a kit for this ($190)

32 spline 205's are a bitch to find, for a decent price anyway.
Click to expand...

Right. I can bore the case no problem. Ill likely have to buy that setup from ORD. Unless i can score a shaft off ebay or trade.

brokenparts said:
32 spline 205s are usually behind th400s.
Click to expand...

Yeah for some reason theres a real lack of 32 spline out here. Not sure why but everything is either 27 or 10.
 
If you are concerned about sealing up the cut stock case then just pony up the extra money for the NWF eco box and do the 241 guts in it. At ~$800 it is by far the best bang for the buck since you get the intermediate shaft with it and unlike a 203/205 kit you are getting a whole new housing for the front case. Fully built 241 style underdrives go for $1,500-$2,000. That is what ORD's Magnum Box is.

Some other things to think about. What gears are in your axles now? If you are considering a 203/205 and then deeper gears at the axles, then going with the 241/205 would mean that you don't have to regear your axles to get the same effect offroad. That alone is a significant cost savings!

Also, I have seen several already built 203/205 doublers with shifters (including the one I purchased) sell for $800-$1,200 on forums like Pirate4x4 because people are going to race cases like Atlas, Hero, etc. to shed weight. If it's a good enough deal and they aren't local, then just have them ship via Fastenal for $150-$200 like I did.

The actual price I paid for my 32 spline in/out 203/205 doubler with triplesticks was $900 and then $150 shipping from TX to TN. Hard to beat that!
 
truck-oholic said:
If you are concerned about sealing up the cut stock case then just pony up the extra money for the NWF eco box and do the 241 guts in it. At ~$800 it is by far the best bang for the buck since you get the intermediate shaft with it and unlike a 203/205 kit you are getting a whole new housing for the front case. Fully built 241 style underdrives go for $1,500-$2,000. That is what ORD's Magnum Box is.

Some other things to think about. What gears are in your axles now? If you are considering a 203/205 and then deeper gears at the axles, then going with the 241/205 would mean that you don't have to regear your axles to get the same effect offroad. That alone is a significant cost savings!

Also, I have seen several already built 203/205 doublers with shifters (including the one I purchased) sell for $800-$1,200 on forums like Pirate4x4 because people are going to race cases like Atlas, Hero, etc. to shed weight. If it's a good enough deal and they aren't local, then just have them ship via Fastenal for $150-$200 like I did.

The actual price I paid for my 32 spline in/out 203/205 doubler with triplesticks was $900 and then $150 shipping from TX to TN. Hard to beat that!
Click to expand...

I read that just a few minutes ago that most of the big names use the 241 guts for there boxes. I can definitely make a seal with the 241 I just wasn't sure what people are doing to seal the large area that gets cut away. I found one picture on Google that someone put a piece of aluminum there but I'm not sure if it's welded to the case. Also I don't know how you'd full the case with oil. Maybe the plug is on the side you need...

I'm definitely going to be doing as much fab as I can for this doubler. If I had time I'd make my own eco box but it might be more of a pain than its worth.
 
Well, look at it this way, doing the 241 underdrive you don't have to regear your axles. That just paid for you to buy the eco box kit. You already need the shaft regardless so . . .

In most cases I am all for doing as much fab as you can but this seems like a no brainer to me. Save yourself the extra work AND end up with a better product than you could make on your own. There is still a good bit of work (labor) involved in building the 241 doubler using the eco box kit, that is why you aren't paying the extra $800-$1,000 for a complete unit. I KNOW you won't be disappointed with the kit, but there is a chance you won't be happy with what you make on your own, especially if you are cutting and reusing the stock 241 case.
 
You must log in or register to reply here.

Latest Posts

Top Bottom