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franken · 03-01-2014, 09:47 PM

I'm working on a similar swap: NV4500, range box (doubler), NP205.

Rather than go with the low 1st 4500 since the 205 is 1.96, I chose to add the 2.6 range box as well. So if I ever complete it, I'll have available lows of 1.96, 2.6 and ~4.5, plus the .75 OD. I think this is about the best combo around unless you go with an Atlas that is mucho dinero.

My understanding was 93-95 had the low 1st, and 96 up had the higher 1st. There's a tag on the top of the trans with numbers and barcode that can be decoded to tell what is/was inside.

There are differences in trans bolt patterns, synchros, and between Mopar and GM, so do some web searching and reading to decide what you want.

Then there're qustions about the clutch and bellhousing. Manual or hydraulic? Stock type w/ the hydraulic actuator part of the throwout bearing, or more conventional? Some have suggested the GM style isn't the best. Then again the AA BH is ~$350, ouch.

What TC, bolt pattern, and spline count do you plan to use?

As I recall. all GM versions, at least 4x4, since that's my interest were 32 spline output, round bolt pattern so your TC should be 32 spline input, round bolt pattern. NP 205s w/ short 32 spline inputs and round bolt pattern don't grow on trees.

I'm not sure the 32/short/round was even made by GM. The 32 sline short input was on something like 73-77 TH400 trucks, and the round pattern case was in something like 85-? trucks. The short 32 spline inputs are on ebay at ~150 used, but I wonder if the seal area is grooved. Don't trust my memory

AA has a spacer that lets you use the late 32 spline long NP205 input.

Try advanceadaptors.com They'll send you a conversion guide (or you can download) with info on what you need to do to make it work. Other 4x4 suppliers have info such as NW fab.

03-01-2014, 09:47 PM	#4
franken Registered User Join Date: Jun 2013 Location: Somewhere Posts: 3,151	Re: on the hunt for a nv4500 I'm working on a similar swap: NV4500, range box (doubler), NP205. Rather than go with the low 1st 4500 since the 205 is 1.96, I chose to add the 2.6 range box as well. So if I ever complete it, I'll have available lows of 1.96, 2.6 and ~4.5, plus the .75 OD. I think this is about the best combo around unless you go with an Atlas that is mucho dinero. My understanding was 93-95 had the low 1st, and 96 up had the higher 1st. There's a tag on the top of the trans with numbers and barcode that can be decoded to tell what is/was inside. There are differences in trans bolt patterns, synchros, and between Mopar and GM, so do some web searching and reading to decide what you want. Then there're qustions about the clutch and bellhousing. Manual or hydraulic? Stock type w/ the hydraulic actuator part of the throwout bearing, or more conventional? Some have suggested the GM style isn't the best. Then again the AA BH is ~$350, ouch. What TC, bolt pattern, and spline count do you plan to use? As I recall. all GM versions, at least 4x4, since that's my interest were 32 spline output, round bolt pattern so your TC should be 32 spline input, round bolt pattern. NP 205s w/ short 32 spline inputs and round bolt pattern don't grow on trees. I'm not sure the 32/short/round was even made by GM. The 32 sline short input was on something like 73-77 TH400 trucks, and the round pattern case was in something like 85-? trucks. The short 32 spline inputs are on ebay at ~150 used, but I wonder if the seal area is grooved. Don't trust my memory AA has a spacer that lets you use the late 32 spline long NP205 input. Try advanceadaptors.com They'll send you a conversion guide (or you can download) with info on what you need to do to make it work. Other 4x4 suppliers have info such as NW fab. Last edited by franken; 03-01-2014 at 09:57 PM.