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Discussion Starter #781
I'm somewhat confused about mounting a late NP205 transfer case to an Allison. In what situation will a 205 bolt up to an Allison without the need for a spacer? Would installing a 29 spline female input or if the 205 already had a female 205 input be sufficient to mate the transfer case and Allison without using a spacer? Female 29 Spline NP205 Input Gear
If you use that ORD input gear, then you can indeed bolt a round pattern 205 directly to a round pattern 4WD Allison tailhousing. You will have to cut out a semi-circle in the t-case mounting face on the trans for the rear shift rail if you go that route. Make sure you have front driveshaft clearance by doing a mock fit-up. This means removing the front shift shaft, which is it's own PITA, but you don't want to notch out your tailhousing for the shifter shaft only to find that you have to clock the t-case up or push it back, both of which involve spacers anyway.

Max, does this look right?

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You got the basics down fine. As far as EFI Live "version", you will need the latest software for the Flashscan. If you are asking which Flashscan, it's going to be the Flashscan V2.

Thanks for all the fantastic info MaxPF. So if I pick up a late model trans and Tcase from a Dmax can I just run my existing 5 speed TCM to get me going? Using my SAE bell and sensor.
Any years of Dmax?
This keeps my wiring stock and if i want to upgrade to the 6 speed in the future its just TCM/wiring change. Buying a 4X4 housing, output shaft and differant Tcase is almost the same cost as a used Dmax setup.
My console shifter just has PRND, there is no reason to have the 1st position from an operational standpoint?
No. The valve bodies in the 5 and 6 speeds use different solenoids with different electrical characteristics. You cannot use a 5 speed TCM on a 6 speed VB or vice-versa. You CAN swap the 5 speed parts (valve body, shifter shaft, internal wiring harness, and external NSBU/mode switch) into a 6 speed, and that WILL allow you to use the 5 speed TCM. Just make sure you keep all the 6 speed parts nice and clean, put away in ziploc baggies or whatever, as you will have to swap them all back in to run a 6 speed TCM.
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