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Has anyone machined a TH400/NP205 short adapter to mate with a 4L80 and D60 Question

Could you use a factory 400 to 203 adapter in addition to the spacer. Curious, cause I have a couple of 400 to 203 adapters and with the spacer I don't know how far off the witdth is compared to a factory 4l80 to 241 adapter. On that note does anyone have a 400 to 203 adapter handy to measure its width??
 
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also if swaping in a 2x4 style tranny. you need to change the oil feed plug at the 3oclock position. 4x4 is solid plug. and 2x4 is pin holed to flow small oil to slip bearing. gm tech told me it will drop pressure on that line and burn up tranny.

gm part#9427692 and less than 5 bucks.
 
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they're called 1.1 (inches?). I just measured one and it is 1-1/8 inches. I would put a pic up but I can't figure out how to reduce the resolution.
 
I am fixing to be doing the 4L80 to 205 swap and have a couple of questions.

I have a 400 to 205 right now and want to install a fixed yoke 4L80.

Does anybody make a spacer/adapter that does not require the tailshaft to be changed to the 4x4 version? If not what is involved in changing the tailshaft? Is it something a tranny shop has to do or can I do it myself?

I am not concerned with the length of the tranny/transfer case. It will be going in my crew cab. The longer the better, the front driveshaft is hating life right now.
 
If your not concerned with length and you have a 2wd 4L80, you might consider a divorced 205. It would give you a better angle on the front shaft.

I looked at your truck on webshot, sharp looking truck; I think you might need some more lift though ;)
 
all you need to do is remove the fixed yoke and slide on the 205 and see how much is left space wise. then add a few thousandths for shaft play. thats how i did it with my 4l80 and old style 205. it came out to 1.25 thick spacer. gave me better clearence at the cv head to tranny pan.

dont forget to swap the plug like i posted just a few days ago.
 
Hey k30, is the shaft length the same for 2 and 4wd on the 4l80s? I've never had my hands on one and just figured 2wd were longer like other trans.

I'm just assuming that fixed yoke is 2wd and would have threads for the nut that holds the yoke on the shaft. Would that cause problems with spline engagement? I'm still pretty new to this and may have my terminology mixed up.
 
Originally thought about using a divorced 205, but never found one. Then I found this post. But it looks like everybody is using a 4l80 with the 4x4 tailshaft. I am just trying to use what I already have and have to shell any unnecessary cash.

Sweetk30 did you use a fixed yoke or 4x4 tailshaft?

GMCburb I am in the process of lowering the truck some right now. Just not sure if it is to big or if I am getting to old to climb in it.:doah:
 
gmcburb1965 said:
I'm just assuming that fixed yoke is 2wd and would have threads for the nut that holds the yoke on the shaft. Would that cause problems with spline engagement?
Click to expand...

The yoke is retained by a bolt that goes into a hole in the end of the shaft.
 
ya 2x4 shafts are longer just like other trannys.

2x4 fixed yoke to 400/205 adaptor. remove the yoke bolt and yoke and tail housing. install custom spacer and bolt all together with longer bolts. dont for get the oil feed plug that needs swaped like i have posted before.

if 84-older 400/205 mount long style 1.25 length spacer.

if 85-up he did it in hear just look i cant recall of the top of my head.
 
This thread is very informative....

Im in the process of putting together a 4l80e/np205........

I have a 4l80e 2WD model, and according to ORD, only the short female 32spline np205 inputs are available now.... which is fine, if my plan comes together............

my question is this:

rather than make a spacer to eat up the extra length on the 2WD (6.25") output shaft, why not just cut it?

this would be easier, cheaper, and IMO better especially for a short wheel base truck.

Im not EXACTLY sure how much spline engagement I should or will have, but unless Im thinking backwards (a possibility), it will work out fine..

Ill keep you guys posted on my findings. So officially, who is building or is running a 4L80E+NP205?

pictures to come..........

mike
 
mike reeh said:
I have a 4l80e 2WD model, and according to ORD, only the short female 32spline np205 inputs are available now....
Click to expand...

Not available? :p:

Since nobody in the Doubler market builds kits for the long 32-spline input... that input should be readily available used.
 
mike reeh said:
This thread is very informative....

Im in the process of putting together a 4l80e/np205........

I have a 4l80e 2WD model, and according to ORD, only the short female 32spline np205 inputs are available now.... which is fine, if my plan comes together............

my question is this:

rather than make a spacer to eat up the extra length on the 2WD (6.25") output shaft, why not just cut it?

this would be easier, cheaper, and IMO better especially for a short wheel base truck.

Im not EXACTLY sure how much spline engagement I should or will have, but unless Im thinking backwards (a possibility), it will work out fine..

Ill keep you guys posted on my findings. So officially, who is building or is running a 4L80E+NP205?

pictures to come..........

mike
Click to expand...

dont forget to change the oil feed plug. and watch for cv head to pan clearence problems if to short. all i did was slid the 4l80 2x4 fixed yoke shaft tranny on my 205 long with adaptor on. got just a hair under 1.25 space left to fill. so i had a 1.25 spacer made to fill the gap and give a tine bit of play in both. and i have more spline engaged on mine than stock ones do. take a look at most thay are about 3/4 -7/8 engaged spline. if you have the full spline tail shaft then cut it to the length needed.
 
So how about some pics of this adapter, sweetk30??

I DID have CV head clearance issues with the 700r4/np205 setup.. I had to beat the corner of the oil pan a little bit... I guess I could go with an adapter.. whos a good machinist around here :)

mike
 
anyone got pics of the 4L80e -> 241 adapter -> 203? What years used the 4l80e to 241 case (donor vehicle)?

BTW- Great info!

edit- I'm going to need a 32 spline 203, yes? Also, will a 2wd 4l80 work with this combo, too long?
 
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Kavik said:
What years used the 4l80e to 241 case (donor vericle)?
Click to expand...

91-99(?) 3/4ton with 8-lug wheels *plus* anything 6-lug w/turbodiesel. The pushbutton NP243 is mixed in though.

th400np241.jpg
 
I know this is an old thread but seemed like the best place to ask. Although a little high at $310, why not purchase the adapter from Advance Adapters? It will mate the 4l80e to a 32 spline 79-84 205 from a 1 ton with a TH400.

Other than cost, is this the easiest? Am I missing something? While I am on a budget, this seems the simplest solution.
 
PsRumors said:
I know this is an old thread but seemed like the best place to ask. Although a little high at $310, why not purchase the adapter from Advance Adapters? It will mate the 4l80e to a 32 spline 79-84 205 from a 1 ton with a TH400.

Other than cost, is this the easiest? Am I missing something? While I am on a budget, this seems the simplest solution.
Click to expand...

what output 4l80-e are you getting or have ?

i found for me with fig 8 205 /400 mount i had and fixed yoke 4l80-e tranny i just had spacer made for 125 and got the oil plug to swap out and 6 longer metric bolts and done.
 
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