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Discussion Starter #1
as some/most of you know i'm looking into doin a 6bt swap and i'm researching how to hook up a spicer 3053A trans to my '93 6cyl CTD and i'm getting some success but its all a bit confuesing to me right now the cummins has a 5spd getrag and np205 married t-case i would keep the getrag but it has issues, jumps out of 4th gear and 3rd and 5th make noise and i've heard that these trannies are costly to rebuild thus my reasoning for the 3053A swap now with the 3053A i know i have to use a divorced t-case and i want to stick with the NP205 because of its strength i do know they make divorced NP205 but at the moment i have two married style NP205 and i was wondering if there is some sort of kit or parts that can be used to convert the married NP205 t-case in my '93 W250 dodge (truck that has diesel) to a divorced style?

thanks
Nate
 

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Nope, the divorced and mated cases are very different castings.

If you have a passenger front diff the old dodges and binders used tons of divorced 205's. If you have a driver diff then the 73 to 77 highboys used a divorced 205 that works good.

If you go divorced, build a strut setup. Divorced cases buck like crazy under hard torque and load.
 

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Discussion Starter #3
The new front axle is going to be a pass. side diff. Dana 60. i do have a 68 binder with the divorced diff but i don't want to part that truck out so i'll have to look around for one, just one question though what do you mean by a strut setup? i'm more then likely going to go divorced because i want to run the spicer 3053A trans so... i've driven my binder around a quite a bit in 4x4 and i've never had it jump on me but i supose theres certain conditions that make it do that, that i haven't had it in so... i don't know

thanks for the input
Nate
 

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Divorced pass side 205s are 50 bucks each around here. In addition to the normal mounts on the top, think about making a strut mount off the rear cover to help combat torque wrap. I did the same thing, 2wd tranny to divoced 205.
Make sure you get solid yokes, not a slip-yoke output on the 205. After you get it, buy new 1410 u-bolt yokes from Jesse at High Angle Driveline. His are machined for u-bolts instead of the stock straps, and cost less then new 1410s from Dana/Spicer. He also sells a sweet rear output flange to disc parking brake setup. I have one and it is really trick.
 

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The trucks that used these divorced 205's had engines that developed less than 400 lb/ft. Put a healthy big block in one or a diesel, strap a 10K pound trailer behind it and hit the hills. You'll see exactly how the t-case bucks.

The 73-77 7700 GVW F-250 4x4's (the extra HD chassis trucks) had a factory strut rod that uses a nice bracket that bolts to the lower rear cover on the 205. There's a 1" steel rod that bolts to that and goes back up to a mount on the frame about 30" back. It does a pretty good job of keeping the case from twisting front to back under load. Polyurathane T-case mounts also help a lot too.
 

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Discussion Starter #6 (Edited)
i know what you mean by the strut system now same concept that was on firebirds/camaros, bar going from the rear axle to transmission to prevent axle hop
for the output on the 205 when you say solid yoke do you mean that were the you joint bolts to on the back of the t-case is apart of the t-case? and not one were it slides in and out? (i'm sure thats what you mean but just verifying)
also to prevent the whole t-case wrap up instead of using rubber/polyurethane mounts could you make up a solid mount? (i'm going to have to custom make my own mouting setup anyways so...)
and also for the shaft between the trans and t-case is there it certain length that it has to be or can it be any length and is there someplace that makes this spicific shaft for a spicer 3053A to a NP205? and if i remember right don't you have to have a slight angle in the shaft to keep the u-joints happy or can it be just straight across

i'm sorry for all the questions and i truly have done research and have found a few things but unless i ask my exact question i'm kinda lost and you all know as well as i do all custom swaps are not the same

thanks
Nate
 

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The U-joint angles at each end of the center driveline have to be exactly the same. In factory divorced t-case installations those U-joint angles were always less than 3.5 degrees. I'd shoot for 2 degrees if possible. Instead of building the mount from scratch, I'd try to get the whole factory crossmember with the transfer case. Would make life a lot easier.

Do not make the t-case fixed to the frame. Steel frames twist. Cast iron cases do not. If you mount the case rigid to the frame you turn it into part of the frame. Twist that frame too much and your case will be in a couple pieces. Plus you'll be able to hear every little noise inside the t-case while your driving if you do. Rubber is good
 

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just like f250 said,

for the output on the 205 when you say solid yoke do you mean that were the you joint bolts to on the back of the t-case is apart of the t-case? and not one were it slides in and out? (i'm sure thats what you mean but just verifying)
Yes

also to prevent the whole t-case wrap up instead of using rubber/polyurethane mounts could you make up a solid mount? (i'm going to have to custom make my own mouting setup anyways so...)
no, bad idea(99% of the time). The rubber helps out the threads stay in the case holes, and you want to try to isolate all the vibrations and noise from the tcase to your ears.

and also for the shaft between the trans and t-case is there it certain length that it has to be or can it be any length and is there someplace that makes this spicific shaft for a spicer 3053A to a NP205?and if i remember right don't you have to have a slight angle in the shaft to keep the u-joints happy or can it be just straight across
short as possible, direct as possible, strait as possible. If you are using two u-joint ends, keep the engine crankshaft parallel to the t-case input shaft.
 

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just like f250 said,

Yes

no, bad idea(99% of the time). The rubber helps out the threads stay in the case holes, and you want to try to isolate all the vibrations and noise from the tcase to your ears.

short as possible, direct as possible, strait as possible. If you are using two u-joint ends, keep the engine crankshaft parallel to the t-case input shaft.
Parallel to the rear diff. (Engine /Trans*=T-case*=Diff*) Late model 4wd Chevy med Duty Trucks have divorced Aluminum case T-cases with D-Max's and ~20k gvw's I don't think they buck to much. Haven't driven them but I can't imagine the alloy case taking alot of bucking in that application.
 

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Why are you running a divorced 205? Several companies mate the Spicer and 205 together with an adapter. Just a thought. In buildups angrypenguin is building a scout with a spicer/205 combo.
 

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I have a divorced 205. Swapping out my 4500 for an auto and getting rid of the 4500 and d-205.
 

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Why not use a Dodge NV4500 5 speed mated to an NP205 (not divorced)? If you already have a Cummins with a Getrag and NP205 it is a straight-forward, bolt-in swap.

The NV4500 is a common and good 5-speed overdrive transmission. Far superior to a Getrag. It replaced the Getrag in Cummins Dodges in '94. There are both Chevy and Dodge, including Cummins, versions. The nut holding 5th gear in place is the only common issue with them and can be remedied.

Here is a great source of info and most every part you might need for the common upgrade of a Getrag to an NV4500: (link deleted due to my newbie status. Sorry)

Edit: OK. I'm brand new here and "must post 10 times before I can post any link", so you will just have to google Quad 4x4 yourself and go see Dan the Gear Man. The rest stands.
 
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