Swappin 3 speed for th350 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

captainron67 · 03-04-2006, 06:26 AM

Do I have to get a different driveline to take the 3 speed out of my truck and put a th350 in? Also what crossmember differences are there if any? Or anything else ive overlooked. Oh its a 67 lwb small window.

70GMCer · 03-04-2006, 07:41 AM

You won't have to cut your drive shaft if it's a 350 turbo "short shaft". You will need an auto x-member, either an auto column w/linkage or auto floor shifter, and an auto trans radiator or cooler. You'll also most likely have to change your speedometer gear in the trans.

captainron67 · 03-04-2006, 02:15 PM

thanks for the info. Also do i have to move the motor forward to the front tower holes or leave in the back?

70GMCer · 03-04-2006, 04:09 PM

not if you already have a V8 in there now. I believe 6cyl engines were set back.

LUV2XCLR8 · 03-04-2006, 08:11 PM

I did this on my 6cyl 70, I only had to have a trans cooler and a crossmember,

Driveshift stayed the same, no idea which tailshaft was on my 350, and get
this we, we modified the 3spd Indy floor shifter I had to work w/ the auto

farside847 · 03-06-2006, 12:07 PM

Would you need a new Auto flexplate, ringgear, starter?

captainron67 · 03-06-2006, 07:29 PM

I have the flexplate/flywheel, torque converter, and transcooler. I need the shifter so I dont have to change columbs, and a crossmember.I installed the v8 to replace the inline 6 but put the motor mounts in the same spot cause i couldnt move it forward with the 3 speed. So I think I need to move the motor forward, but do i need new mounts to do this?Any other info would be great thanks.

Richard Dobson · 03-07-2006, 01:43 PM

What happens with the clutch and brake pedals? Do you have to swap them out with an automatic pedal set? I am getting ready to swap out my 250 six and three speed on the column so I can learn from this. Thanks

Mechdawg · 03-07-2006, 04:29 PM

I have just pulled out my 6cyl I will be putting a 327 in its place however I do not beleive you have to move the engine forward I may be wrong. I still havnt put mine in yet waiting on a flywheel I will be putting my gm 3 speed back in since its all I have right now.

captainron67 · 03-14-2006, 09:08 PM

So after all this I am now thinking I want to stay with a stick shift soo does anyone know of a good 4 or 5 speed trans that will bolt in with minor mods?

03-04-2006, 06:26 AM	#1
captainron67 Registered User Join Date: Feb 2006 Location: Marysville Washington Posts: 13	Swappin 3 speed for th350 Do I have to get a different driveline to take the 3 speed out of my truck and put a th350 in? Also what crossmember differences are there if any? Or anything else ive overlooked. Oh its a 67 lwb small window.

03-04-2006, 07:41 AM	#2
70GMCer Senior Member Join Date: Apr 2005 Location: Joppa, Maryland Posts: 4,408	Re: Swappin 3 speed for th350 You won't have to cut your drive shaft if it's a 350 turbo "short shaft". You will need an auto x-member, either an auto column w/linkage or auto floor shifter, and an auto trans radiator or cooler. You'll also most likely have to change your speedometer gear in the trans. __________________ 1997 GMC Sierra Ext 1965 Mustang

03-04-2006, 02:15 PM	#3
captainron67 Registered User Join Date: Feb 2006 Location: Marysville Washington Posts: 13	Re: Swappin 3 speed for th350 thanks for the info. Also do i have to move the motor forward to the front tower holes or leave in the back?

03-04-2006, 04:09 PM	#4
70GMCer Senior Member Join Date: Apr 2005 Location: Joppa, Maryland Posts: 4,408	Re: Swappin 3 speed for th350 not if you already have a V8 in there now. I believe 6cyl engines were set back. __________________ 1997 GMC Sierra Ext 1965 Mustang

03-04-2006, 08:11 PM	#5
LUV2XCLR8 The LuvShack Garage Join Date: Jan 2004 Location: Maple Grove, TN (West Side) Posts: 30,468	Re: Swappin 3 speed for th350 I did this on my 6cyl 70, I only had to have a trans cooler and a crossmember, Driveshift stayed the same, no idea which tailshaft was on my 350, and get this we, we modified the 3spd Indy floor shifter I had to work w/ the auto __________________ Owner/Op: "TN Classic Transport Carriers" The Toy: "Square Vette" 72 Hybrid Blazer Toy Barn: "LuvShack" 40 x 60 x 20 Shop Tow Piggy:"Maddy" 88 Silverado 3500 Hauler: "Feathers" 14 Aluma 8218T

03-06-2006, 12:07 PM	#6
farside847 Registered User Join Date: Feb 2005 Location: Bay Area, California Posts: 995	Re: Swappin 3 speed for th350 Would you need a new Auto flexplate, ringgear, starter? __________________ 1971 Chevy C10 Shortbed Stepside, 307v8 3-on-the-tree

03-06-2006, 07:29 PM	#7
captainron67 Registered User Join Date: Feb 2006 Location: Marysville Washington Posts: 13	Re: Swappin 3 speed for th350 I have the flexplate/flywheel, torque converter, and transcooler. I need the shifter so I dont have to change columbs, and a crossmember.I installed the v8 to replace the inline 6 but put the motor mounts in the same spot cause i couldnt move it forward with the 3 speed. So I think I need to move the motor forward, but do i need new mounts to do this?Any other info would be great thanks.

03-07-2006, 01:43 PM	#8
Richard Dobson Registered User Join Date: Apr 2003 Location: Easley, South Carolina Posts: 491	Re: Swappin 3 speed for th350 What happens with the clutch and brake pedals? Do you have to swap them out with an automatic pedal set? I am getting ready to swap out my 250 six and three speed on the column so I can learn from this. Thanks __________________ Richard Dobson

03-07-2006, 04:29 PM	#9
Mechdawg Registered User Join Date: Jul 2002 Location: Dover AFB Delaware Posts: 159	Re: Swappin 3 speed for th350 I have just pulled out my 6cyl I will be putting a 327 in its place however I do not beleive you have to move the engine forward I may be wrong. I still havnt put mine in yet waiting on a flywheel I will be putting my gm 3 speed back in since its all I have right now.

03-14-2006, 09:08 PM	#10
captainron67 Registered User Join Date: Feb 2006 Location: Marysville Washington Posts: 13	Re: Swappin 3 speed for th350 So after all this I am now thinking I want to stay with a stick shift soo does anyone know of a good 4 or 5 speed trans that will bolt in with minor mods?



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