CUCV M1008 Auto to manual conversion

[Hiluxxulih]

I am looking into a CUCV M1008 that has a crack in the transmission output area , is it possible to swap the turbo 400 auto for an SM465 4 speed from a 1986 Chevy 3/4 ton with a 350 ? I have the complete truck also will the clutch pressure plate and flywheel and bell housing from a 350 work on a 6.2 diesel ?

[ECU PIRATE]

You should be in good shape bro for the swap. Everything should move right over. I am doing the same kind of swap but in a 2wd short bed. Be sure to have your flywheel turn and get new pilot and throw out bearings. You will most certainly have to move your transmission cross member forward due to the different tranny lengths. Let me know how it turns out.....

[rcbildr]

The flywheel will not work, you will have to get one for a 6.2L diesel. I'm not sure if the 350 clutch will work either. It may bolt up, but I remember the clutch I had in my burb had a 12" disk and I don't know what is used in gas trucks. The bellhousing should work. One thing you migtht have problems with is the starter. The starter I had in my burb when it was an auto (it originally had a 700R4, then I converted it to an SM-465, then I went back to a TH-400) would not work right with the manual trans setup. The starter gear would not retract far enough so when the engine was running it would also spin the starter.

I will also be doing a similar swap with my 83 shortbed 4x4 diesel. I ruined the 700R4 in it and can't afford a rebuild right now and I have almost all the parts needed to put in an SM-465/NP-203....all I need is the drive shafts and maybe the crossmember.

[hatzie]

Originally Posted by ECU PIRATE

You should be in good shape bro for the swap. Everything should move right over. I am doing the same kind of swap but in a 2wd short bed. Be sure to have your flywheel turn and get new pilot and throw out bearings. You will most certainly have to move your transmission cross member forward due to the different tranny lengths. Let me know how it turns out.....

The 350 flywheel, friction disc, and pressure plate is not right for the Detroit 6.2l 6.5l engines. Even if it did bolt up they are not balanced for the diesel.

Good used 6.2 flywheels can be bought bought easily and cut cheap. New 6.2 alignment tool, pressure plate, friction disc, and throwout bearing "clutch kits" are easy to get.

The 6.2 has a GM corporate bell-housing bolt pattern. I think the bell-housing dust cover might differ at the starter and around the rear main seal for the diesel engine.

The clutch master may not have the holes pre-drilled in the firewall. The hydraulic clutch has firewall to master cylinder support rods riveted to the pedal assembly. Probably to avoid tearing out the firewall at the clutch master like my Dad's 88 F250 7.3 did.

Everything else should just bolt in.

[lindstromjd]

Originally Posted by Hiluxxulih

I am looking into a CUCV M1008 that has a crack in the transmission output area , is it possible to swap the turbo 400 auto for an SM465 4 speed from a 1986 Chevy 3/4 ton with a 350 ? I have the complete truck also will the clutch pressure plate and flywheel and bell housing from a 350 work on a 6.2 diesel ?

You need a diesel specific flywheel and clutch assembly. Even if the SBC stuff bolts up to the diesel, the diesel will tear them to pieces because of the extra vibrations it creates. 6.2's are EXTERNALLY balanced by using the flywheel, SBC's are internally balanced. You'll ruin a lot of internal parts on your diesel if you run gasoline parts like that.

Good luck with the swap.

[ECU PIRATE]

Nice.........I learn something new every day. This is what this place is for.

[67_SS396]

When I did the swap, I ordered a flywheel from rockauto. Swaping the pedal assembly is a pain in the rear. Take the time to swap to a hydraulic clutch if you plan to take your truck offroad.
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[GM72K10]

Amen to the hydraulic clutch, if you're doing the swap find that setup. My 86 6.2L K30 dump has the hydraulic set up, my 83 K30 350 doesn't, its like night and day.