Manual transmission swap

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pmehringer001

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I have a 1986 D30 with 6.2-th400-np208. I have an 80’s sm465-np208, and a 70’s sm465-np205. I plan to use the 205 t-case. But is there any differences between the transmissions being 70’s vs 80’s? Is one better/stronger than the other? Slightly different gear ratios? I had already bought a rebuild kit for the 80’s trans but would it work for the 70’s trans if I decide to use that one?
 

SquareRoot

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Hi. There might be minor differences in the transmission years, I don't know but someone will. I know about 205 t-cases and NV4500's and auto to manual conversions. Do you plan on a mechanical or hydraulic linkage? 85-87 came OEM with hydraulic you know. Do you have the pedal assembly yet? Vacuum or hydraboost? Not trying to be nosey but I can help you out with info and parts if need be.
 

nvrenuf

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'84 and older 465/205: the 465 has a male 10 spline tailshaft, the 205 has a male 10 spline input shaft and they are joined but a coupler sleeve. These will have a tall figure 8 bolt pattern adapter.

'85+ 465/205 and all 465/208: the 465 will have a long male 32 spline tailshaft, the tcase will have a female 32 spline input shaft. The 465/205 will use a short round bolt pattern adapter. Iirc, the '84 and older 465/208 will have a tall adapter where the '85 will be the short style.

Gear ratios in the early and late 465's are the same. Aside from the tailshaft, I believe all of the parts in the rebuild kit will interchange.
 

pmehringer001

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Hi. There might be minor differences in the transmission years, I don't know but someone will. I know about 205 t-cases and NV4500's and auto to manual conversions. Do you plan on a mechanical or hydraulic linkage? 85-87 came OEM with hydraulic you know. Do you have the pedal assembly yet? Vacuum or hydraboost? Not trying to be nosey but I can help you out with info and parts if need be.
I plan on using hydraulic clutch. I don’t have any of the pedal or pedal related parts yet. It is hydro boost brake system.
 

PrairieDrifter

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I plan on using hydraulic clutch. I don’t have any of the pedal or pedal related parts yet. It is hydro boost brake system.
The pedal and bellhousing/related parts are hard to find and expensive.
 

pmehringer001

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The pedal and bellhousing/related parts are hard to find and expensive.
Yeah thats what I’m coming to find out . I have a hydraulic throw out bearing thats supposed to take place of the manual one with the same bell housing. Pretty much all I need now is the pedal assembly, slave cylinder, and hydraulic line/resevior.
 

SquareRoot

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I know someone who has those hard to find parts ;)
 

Zelph

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Fat 454

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Novak transmissions sell ( or used to ) a hydraulic conversion kit for a chevy bellhousing. Good source of transmission swap info as well.
 

bucket

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Novak transmissions sell ( or used to ) a hydraulic conversion kit for a chevy bellhousing. Good source of transmission swap info as well.

I believe they still do.
 

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