[SeaBass44]

After much searching, I am still I found a BB chevy and a nearly new rebuilt T400 2wd, 72 3/4 ton truck. I have a 360 dodge, 435 and D300 tcase. 99% sure the 208 and D300 both bolt up the same, as in if a 208 is bolted up to a trans, a d300 will bolt right up. my question is.....I want to use this 402 BB chevy and T400, and want to use my d300, can the 2wd trans be converted to 4x4? is it cost efective to do so? is there a different tcase I could use that would be simplier or cheaper, or better? I am at 103:1 with a stock d300 & 5:89 gears, I like it, I sold a 4:1 gear set I had for the 300 because I am low enough as it is. I am going to go find the AA site, I think they will ber the highest priced option, I'm only doing this swap because I can get this motor trans very very cheap. I will keep the dodge motor in untill I have everything for the swap, trying to do it cheap. I will also need a cooler for the trans, is an aux cooler enough or do I need to use the one built into a radiator?
As always, any all help isw much aprecated I thought about postinmg this in the chevy fourm, but thought most those guys hang out in here anyway, if responce is bad, I will delete this and ask there

 

[masonmachines]

I believe the two wheel drive 400 will have a 32 spline rear output if that helps

 

[SeaBass44]

I believe the two wheel drive 400 will have a 32 spline rear output if that helps

all info helps! Thank You, from my reading seems like all the 400's are 32 spline, 350's are 27?

 

[Wilson]

D300's are 23 spl. For it to "bolt up" to a 208 adapter, the shaft dia and spline count will have to amtch up...as well as the bolt pattern.

Your simplest and cheapest way to do your swap is with a divorced NP205. The big block torque will get you as far as the gearing in your NP435.

 

[SeaBass44]

D300's are 23 spl. For it to "bolt up" to a 208 adapter, the shaft dia and spline count will have to amtch up...as well as the bolt pattern.

Your simplest and cheapest way to do your swap is with a divorced NP205. The big block torque will get you as far as the gearing in your NP435.

AA site is confusing as hell says I need 2 adapters at $546 each GM TH400 2WD & 4WD Trans. Dana 300
[P/N 50-6400
$546.00
& 50-6404]
$546.00

looks like what you say a 205 might be the way to go. as long as it's not to long? I'm at 108" wb, so it might be ok.where do I find a divorced NP205.? or should I do a divorced toy mini? Na to much torque:nuke:

 

[Go2Guy]

If you've got a 208 to 400 adpter all you need is to gut the 400, cut the output to size and respline it- cheap and effective- John Loyd's shop can help- they do this all the time 417 744 2721.

You can also get the older factory adapters that put t400's to a dana 20. and run the dana 20 if you are OK with that gearing- it will bolt right up to the 400 without touching it. If you do drags and you get the rig hooking up you'll take out the adapter on the 1-2 shift (I used to do mud drags)

Good luck!

 

[SeaBass44]

If you've got a 208 to 400 adpter all you need is to gut the 400, cut the output to size and respline it- cheap and effective- John Loyd's shop can help- they do this all the time 417 744 2721.

You can also get the older factory adapters that put t400's to a dana 20. and run the dana 20 if you are OK with that gearing- it will bolt right up to the 400 without touching it. If you do drags and you get the rig hooking up you'll take out the adapter on the 1-2 shift (I used to do mud drags)

Good luck!

no I don't. I have a 2wd t400, I have a dodge 435 with a d300 attached to it.

 

[61_chevy_4x4]

Only difference between a 2wd short tail housing th400 and a 4x4 th400 is the oil seal grove cut into the shaft.

 

[fatconnors]

i bought the AA kit for chevy 400 to D300 and used a 2wd tranny. i had to take the tailshaft housing off, gut the tranny, and replace the output shaft with the one AA supplied. once the tailshaft housing is off the back of the tranny, the AA adapter will bolt right to it.

 

[SeaBass44]

i bought the AA kit for chevy 400 to D300 and used a 2wd tranny. i had to take the tailshaft housing off, gut the tranny, and replace the output shaft with the one AA supplied. once the tailshaft housing is off the back of the tranny, the AA adapter will bolt right to it.

was tha hard? or do you know auto trannys? did you buy one or both of the part #'s I listed? in otherwords how much $ was the part. And would I need to have a trans shop install it?
thx

 

[FULLSIZE]

the most cost effective way? find a GM bellhousing and modify it for the dodge trans cause autos suck. :flipoff2:

 

[High5]

before i went to an atlas i ran a d300 on my th400 using a stock chevy np208 adapter and an advance adaptersinput shaft in my d300. the d300 input shaft is easy to swap. personally i knew i was going to be swapping an atlas in and i didn't want to cut down the size and spline count of the stock th400 output. this is why i opted for the input shaft change on the d300. when it came time for the atlas i just ordered it with the correct input spline count to match the th400. my th400 is the 4x4 version though.

BTW with the chevy 208 adapter one hole will have to be redrilled to line up. all of the rest already do.

 

[SeaBass44]

the most cost effective way? find a GM bellhousing and modify it for the dodge trans cause autos suck. :flipoff2:

Ya I know:flipoff2: But that sounds like work They might make a chevy to 435 bell anyway....???But I planed on selling the 360/435 to someone to recoop some $$:flipoff2:

 

[Scoutillac]

I run a th400 (2wd) and a 300. I pulled the main shaft, had a buddy reslpine it, found an adapter at the bone yard . Complete disassambly of the trans will be required.

 

[SeaBass44]

I run a th400 (2wd) and a 300. I pulled the main shaft, had a buddy reslpine it, found an adapter at the bone yard . Complete disassambly of the trans will be required.

what adapter? off what trans and transfer? did you have to shorten the shaft or just respline?

 

[Wilson]

before i went to an atlas i ran a d300 on my th400 using a stock chevy np208 adapter and an advance adaptersinput shaft in my d300. the d300 input shaft is easy to swap. personally i knew i was going to be swapping an atlas in and i didn't want to cut down the size and spline count of the stock th400 output. this is why i opted for the input shaft change on the d300. when it came time for the atlas i just ordered it with the correct input spline count to match the th400. my th400 is the 4x4 version though.

BTW with the chevy 208 adapter one hole will have to be redrilled to line up. all of the rest already do.

I'm only running 5 of 6 bolts on my d300 crawler, the last one won't ft with my sm465 adapter....... I'm going to find a way to get it in there though.

 

[Brad]

Hey Darren, this what u need?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2446715466&category=33727

 

[Stephen]

If you have the TH400 shaft that sticks out 4.5", you could probably use a round GM 205 adapter and cut the trans output shaft off (without removing it from the trans) and use a 32 spl. input in the D300 and make it all bolt up. Typically the 32 spline shafts have LOTS of spline on them, especially the 2wd shafts. We have a 32 spline input for the D300 that would make this work.
If the trans output has enough spline and you don't have to worry about driveshaft to pan clearance, you could look at cutting more of the shaft off and using a TH400 to NP208 adapter as mentioned above, it's a bit shorter but uses the same bolt pattern. This 400/208 adapter would be the best choice since it's pretty cheap and available.

 

[fatconnors]

was tha hard? or do you know auto trannys? did you buy one or both of the part #'s I listed? in otherwords how much $ was the part. And would I need to have a trans shop install it?
thx

this was my first auto tranny experience, it wasn't too bad but there were parts as far as the eye could see once i had everything out to get at the output shaft. my bad about the AA thing, i checked my records and i got the novak adapter, i think i did that because novak was cheaper. 410 bucks plus shipping, big bucks but if you can get the tranny cheap enough like i did it's not too bad. i bought a TH400 rebuild video to help out, but it just made me fall asleep. i wouldn't bother paying a place to do it, it only took basic tools and not really that much time.

 

[High5]

i forgot to mention that when i ran a d300, 4wd version th4oo that came with the 208 and adapter i have to shave about 1/8" off the output shaft. as i stated earlier i have a 32 spline input in my d300 from advance adapters. i have since put in a different th400 in and it too came with the 208 but my current atlas t-case did not require me to shave 1/8" off.