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mattshea125 · 01-17-2020, 10:46 AM

Looking for some input from anyone with a 3/4 ton 4x4 that is running a TH350 / NP205 transmission.

I have a 1978 K20 with this transmission / transfer case combo and will be putting a stock 454 big block in place of the tired 350 this year.

The transmission currently functions perfectly, but I am wondering if I should swap it to a TH400 / NP208 or just rebuild what I have so I don't have to change my whole driveline around.

The truck is used for weekend driving, picking up mulch and some towing, nothing too crazy. I rarely if ever take it off road or beat on it.

01-17-2020, 10:46 AM	#1
mattshea125 Registered User Join Date: Jan 2008 Location: Riegelsville P.A Posts: 38	K20 with TH350/NP205 Looking for some input from anyone with a 3/4 ton 4x4 that is running a TH350 / NP205 transmission. I have a 1978 K20 with this transmission / transfer case combo and will be putting a stock 454 big block in place of the tired 350 this year. The transmission currently functions perfectly, but I am wondering if I should swap it to a TH400 / NP208 or just rebuild what I have so I don't have to change my whole driveline around. The truck is used for weekend driving, picking up mulch and some towing, nothing too crazy. I rarely if ever take it off road or beat on it.