Ultimate OBS GMT400 Auto to Manual Transmission Swap Video

In this video, I show the journey of taking my 1998 K1500 with a 4L60E automatic transmission and converting it to an NV3500 manual transmission. This same process can be used as a reference for 1988-1998 and up Old Body Style (OBS) GMT400 platform vehicles. Be sure to like, share and subscribe for more upcoming OBS Chevy adventures!

My 1998 OBS Chevy K1500:    • No regrets buying this old GMT400 truck!  

GMT400 clutch pedal differences:    • OBS GMT400 Clutch Pedal Assembly Diff...  

Helpful NP241 & NP243 transfer case disassembly videos:
(part 1)    • 243C Transfercase / 98 Chevy 1500 /5.7L  

(Part 2)    • 243C Transfer case / 98 Chevy 1500  

Company that tuned engine computer to remove auto trans check engine light faults after swap (Sinister Performance): http://www.gmtuners.com/

Major parts list to complete auto to manual swap:
1.) NV3500 or NV4500 manual transmission
2.) Flywheel with factory shim
3.) Clutch kit (typically includes clutch disk, pressure plate, pilot bearing/bushing, and throw out bearing)
4.) Clutch master cylinder with line
5.) Clutch pedal assembly. Ensure you get the correct year pedal assembly for your vehicle
6.) Electrical pigtail for clutch safety/position switch on pedal assembly (1988-1995 should use 2 wire Standard Motor Products #S1646 & 1996+ 4 wire GM #12129136)
7.) Electrical pigtail for backup lamp sensor on manual trans GM #12103584
6.) Shift boot and shift knob
7.) If originally equipped with a 4L60E, need a 32 spline transfer case input shaft for NP241 & NP243 (4L60E vehicles typically come with 27 splined input shafts for t-case) https://www.usastandardgear.com/shop/...
8.) [Optional addition] factory manual trans steering column clamshell trim
9.) [Optional addition] factory manual speedo cluster

Tools used in video:
1.) 2" hole saw bit to create firewall clutch master cylinder hole: https://amzn.to/3VQtUJM
2.) 3/8-16 rethreading tool: https://amzn.to/3P9eYTu or M10X1.5 rethreading tool for exhaust manifold studs: https://amzn.to/40953Uh
3.) Craftsman 3/8 flex head ratchet: https://amzn.to/4iSRTCb
4.) Rivenut/thread insert tool: https://amzn.to/41M0oIU
5.) 15mm flex head ratcheting wrench: https://amzn.to/4iLQDAH

Parts used in video:
1.) Weatherhead by Danfoss inverted flare plug (WH 131 x 6). Need 2 fittings to block the ports where the trans cooler lines went into radiator https://www.napaonline.com/en/p/WH_131X6
2.) MAHLE F17990 exhaust manifold to y-pipe donut gaskets (2 required): https://amzn.to/4gsvD0j
3.) Walker 31575 y-pipe to muffler exhaust gasket: https://amzn.to/40953Uh

Instagram @ weakest of weeks:   / weakestofweaks  

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