1-tonmudders 241/205 Doubler

[1-tonmudder]

After much deliberation and study I decided to build a 241/205 doubler instead of the traditional 203/205.My main reason for doin so was more lo-range(5.33-1) and lesss money.I'm usin the 241/205 kit from D&D machine(360-779-2500).Kit includes 241 adapter plate,indexing ring,shaft,and misc hardware. $514 shipped.

This kit is built around the round pattern 205 and a DSD 241 case that can be found in the late 80's Chevy/GMC trucks that had the SM465 4speed trans or the late 80's/early 90's model trucks with the 4L80E automatic trans.My 205 case was pulled from a 89 model 3+3 with the SM 465 trans.

I started with a teardown and inspection of things.Case was real clean inside.

That was pretty much it for the 1st day,but I did put the indexing ring on just to get an idea of how much I can clock it and I ordered some seal's for it.

 

[1-tonmudder]

This was spread out over a 2-3 day period of working on it a little at a time.I went to Napa and got a roll of cork gasket material to make my gaskets with..

After that I put the LH shift rail back in to determine where it would need cut.I cut it two inches from the end.

Since the index ring covers the hole for the shift rail you can't use it.

So I capped it with a 1-1/4 freeze plug.

I am twin sticking the 205 while it's apart so I notched the rails too.

Sice I have plugged one of the shift rails I have to run the rail out the back of the case.

So while we were at lunch one day we stopped by one of the local machine shops and picked up a scrap piece of 3/4 cold rolled rod.

I beveled both the rod and the shift rail so the weld would penetrate good.

I couldnt find a piece of angle that I didnt have to go out in the rain and cut off so I broke a piece of 16ga to lay the rod and rail in while welding.

I had the rail/rod tigged together

I spent about an hour smoothin it out to it would'nt bind when shifted.

Next on the list was to drill out the tailsection so the new shiftrail could go thru it.I used the rail print on the tailsection to go by and just center punched it and drilled it.

The rod/rail is 3/4 so I drilled it 7/8 to give it plenty of room to pass thru.This will give you an ideal of what it will look like.

I'm sure somebodies noticed how close the rail is the the speedo hookup,so to remedy that Im goin to use a Dodge 205 tailsection.The Dodge is the very same it just puts the speedo on the opposite side of the case

 

[1-tonmudder]

The 241 I got was basically a core.It had a big hole knocked in the back 1/2 of the case from where the chain had broken.All the needed parts for the doubler were still good and for $50 I bought it.

This is all the parts from a 241 thats needed.

The kit came with no instructions at all,and there is very little info on the net about a 241/205 doubler.So with that bein said here's where I messed up.I ride with a guy who has a 231/300 doubler that was built usin D&D's kit.He said to cut the case along the casting mark.

WRONG!!! I know I should have checked before cuttin it but I didnt and it wound up bein about an 1/2 inch short in some places.So that put me to findin another case 1/2.I use to work at a trans shop and luckily enuf he had another one.I assume the 231's are cast a little different than the 241's.

I went and got another case and started over(after takin careful measurements).I used a port a band to cut it.

The kit comes with an alum slug to weld in but for some reason I didnt get one and wasnt waitin for it to get here so I used some square alum stock we had to plug the gap.The slug will need to be tapped for the bolts to seal off that end of the case.


Drake spent about 30 min weldin it up.

While he done that I made more gaskets.

I spent about 20 min with a file cleanin it up so it would seal good.

Here's what it looks like finished.

 

[1-tonmudder]

No real work done to it today,but I did get my case back from the machine shop.I had the case bored to accept a seal for the new shift rail.

 

[rcamacho]

Nice thread, it's interesting to see another approach to the usual atlas or 205+203.

 

[NorCalKid]

Cool to see someone doing something different. Hows the length of yours compare to a regular 203/205?

 

[supersize75k5]

damned thats aot of wok and effort, it seems you have access to the needed help or tools though so its with in your ability, I dont see this as a realistic option though for most people!

at anyrate

 

[1-tonmudder]

damned thats aot of wok and effort, it seems you have access to the needed help or tools though so its with in your ability, I dont see this as a realistic option though for most people! at anyrate

I agree that it's alot of work but the only thing that will compare in ratio to this is a $1000 more + to buy/build(Black box,Stak,Atlas) so for the price difference/versus gain I'll do the work.

Yeah I am fortunate to have ability,acess to parts and tools,but anybody could do what I have done.The case was sent out to a machine shop to be bored at a cost of $45,the rod for the shift rail was $4.The shift rails were modified with a grinder,the tailhousing with a drill press and about any welding shop could do the case welding,so it would not be out of the relm of possibilites for the average guy.

 

[nvrenuf]

Very cool set up, I like the added low range. How much length does it add to the assembly? Can't wait to see pics of the combo bolted together.

 

[1-tonmudder]

How much length does it add to the assembly?

I honestly dont know,I haven't even thought about measuring it.

 

[Hogback Fabrication]

Nice, I actually just pulled all my 241/205 stuff out of the basement today and started assembling everything (I'm making the aluminum adapter myself). I also decided to shift the 205 from the front, I'm going to notch the 241 case to clear the shift rail.

Keep us updated as you finish, I will start a thread for mine when I get it done too

 

[dfl701]

It looks good! Can't wait to see this bolted up

 

[rwright07]

subscribed... planning on building one in the future

 

[muddermilitia]

Keep us updated as you finish, I will start a thread for mine when I get it done too

Please do, I have a passdrop 241 and a ford 205 that im saving for the buggy build

 

[Greg72]

Good job..... it's always fun to see something innovative and different around here.

 

[BGKYK5]

Very Nice Keep the details comming!

I really want to go this route as well. I can see why people who already have a 203 the bolts up to their trans would run a 203/205, but I have always liked the idea of a 241/205 a lot better - not only is it lighter and easier to package, but you actually get 4 different gears - 1:1, 1.96:1, 2.73:1 and 5.33:1 (I don't count 1.96:1 and 2:1 as two different gears with the 203/205 )

I know a guy who TIG welds aluminum and is very handy with a mill, so I'd be all set once I get the parts. I am trying very hard to justify going straight to a 241/205 over just SYE-ing my 241.

If I had the $$$ I'd skip all the hard work and go right to a Klune-V or Blackbox with a 205, but the internals are the same.

 

[1-tonmudder]

I had decided to go with the black box but somebody on another board(K204dr I think) suggested a 241/205 doubler.After talkin to Duffy at D&D I decided on it instead.

 

[86-1ton]

subscribed... it's different, gives you something to think about... what are your plans for use...? rocks, trails, just mud...?

 

[1-tonmudder]

All the above.I mostly ride @ Harlan KY and they have it all there.Everybody I ride with is doubled or have Atlas's or something and run the hard(er) stuff so with just one case I have to really flog mine to get it to go.

 

[86-1ton]

awesome... just around here we have trails and mud... i'm not really looking to go into rock crawling, even though our local race track is opening up a rock course... too hard on stuff...

i'd really like to see this come together and see the reliability... i want to put a 465/203-205 in mine... maybe this'll sway me...