what is the 4sp manual in a 68 3/4 ton - The 1947 - Present Chevrolet & GMC Truck Message Board Network

coggonobrien · 04-19-2008, 10:07 PM

just wondering what the name is and if there's any aftermarket support for it performance wise. i'm buying a 68 3/4 ton chevy longbox 2wd.
thanks,
Dave

kyull67 · 04-19-2008, 10:10 PM

I believe it should be the SM465. Does it have the granny gear. They are supposed to be pretty strong. If I'm incorrect someone will let us know.

cruiserman · 04-19-2008, 10:28 PM

Yep, sm465

sm420 up to 1967.

Cast iron and fairly bulletproof. Just keep it full of fluid.

**kwmech** · 04-19-2008, 10:31 PM

Got an NP435 in my 68 GMC

lilred67 · 04-20-2008, 12:06 AM

Quote:

Originally Posted by kwmech

Got an NP435 in my 68 GMC

what motor do you have in front of it? i have a '68 gmc 3/4ton with a 305 v-6/ 4-speed and was wondering what tranny it had....thanks

coggonobrien · 04-20-2008, 12:31 AM

cool thanks, is there a hurst shifter that will work with it?

**WorkinLonghorn** · 04-20-2008, 01:26 AM

It's either the 465 or the NP 435 Close Ratio as mentioned above.

Quote:

cool thanks, is there a hurst shifter that will work with it?

Don't know about that,but don't be expecting any fancy shifts with one of these,they aren't designed for it.

factorystock · 04-20-2008, 01:27 AM

The SM 465 was the standard 4 speed in 68. I believe the NP 435 was the close ratio option, but still a heavy duty 4 speed with low 1 st gear.The NP has an aluminum top cover. Both have the reverse on the right side and down.The SM 420 was last used in 67 (reverse is on the left side and down).These transmissions are not designed for performance, were designed to do work and stay out of the repair shops.

67_C-30 · 04-20-2008, 02:12 AM

I agree totally with factorystock and WorkingLonghorn.

lilred67, the NP435 is pretty common behind the V6's. I have one truck with a 351E V6 and another with the 305E V6 and they both have the NP435. The easiest way to tell is look under the truck and see how many PTO plates it has. In a '68 if it has 2 it will be a SM465 and if it has 1 it will be the NP435. This only applies to the '68 - up models because the '67 will not have a SM465 option. It will either be the SM420 or NP435, and you can tell which is which by where the reverse gear is on the shift pattern as factorystock said.

msgross · 04-20-2008, 02:27 AM

Here is my 465 from the 68 K-10. of course it has a transfer case behind it though....

GMCBubba · 04-20-2008, 11:00 PM

no guarantee that the NP 435 is close ratio. i seem to have the np435gl with the super low granny gear. i think. originally came behind a 307. definitely not a drag racing setup. but good for it's original purpose of hauling a bed and trailer full of grain or hay.

04-19-2008, 10:07 PM	#1
coggonobrien Registered User Join Date: Mar 2008 Location: Coggon, IA Posts: 580	what is the 4sp manual in a 68 3/4 ton just wondering what the name is and if there's any aftermarket support for it performance wise. i'm buying a 68 3/4 ton chevy longbox 2wd. thanks, Dave

04-19-2008, 10:10 PM	#2
kyull67 Registered User Join Date: Nov 2006 Location: Springfield/Kansas City Posts: 1,842	Re: what is the 4sp manual in a 68 3/4 ton I believe it should be the SM465. Does it have the granny gear. They are supposed to be pretty strong. If I'm incorrect someone will let us know. __________________ The first '67 The current '67 '63 Biscayne

04-19-2008, 10:28 PM	#3
cruiserman Registered User Join Date: Dec 2006 Location: Idaho Posts: 210	Re: what is the 4sp manual in a 68 3/4 ton Yep, sm465 sm420 up to 1967. Cast iron and fairly bulletproof. Just keep it full of fluid. __________________ 72 C2500 LWB 402 Sierra Grande 05 Odyssey 08 Tundra Last edited by cruiserman; 04-19-2008 at 10:30 PM.

04-19-2008, 10:31 PM	#4
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,658	Re: what is the 4sp manual in a 68 3/4 ton Got an NP435 in my 68 GMC

04-20-2008, 12:31 AM	#6
coggonobrien Registered User Join Date: Mar 2008 Location: Coggon, IA Posts: 580	Re: what is the 4sp manual in a 68 3/4 ton cool thanks, is there a hurst shifter that will work with it?

04-20-2008, 01:27 AM	#8
factorystock Registered User Join Date: Feb 2007 Location: west coast Posts: 3,396	Re: what is the 4sp manual in a 68 3/4 ton The SM 465 was the standard 4 speed in 68. I believe the NP 435 was the close ratio option, but still a heavy duty 4 speed with low 1 st gear.The NP has an aluminum top cover. Both have the reverse on the right side and down.The SM 420 was last used in 67 (reverse is on the left side and down).These transmissions are not designed for performance, were designed to do work and stay out of the repair shops.

04-20-2008, 02:12 AM	#9
67_C-30 I have a radical idea! Join Date: Jan 2005 Location: Sweet Home Alabama! Posts: 6,513	Re: what is the 4sp manual in a 68 3/4 ton I agree totally with factorystock and WorkingLonghorn. lilred67, the NP435 is pretty common behind the V6's. I have one truck with a 351E V6 and another with the 305E V6 and they both have the NP435. The easiest way to tell is look under the truck and see how many PTO plates it has. In a '68 if it has 2 it will be a SM465 and if it has 1 it will be the NP435. This only applies to the '68 - up models because the '67 will not have a SM465 option. It will either be the SM420 or NP435, and you can tell which is which by where the reverse gear is on the shift pattern as factorystock said. __________________ '67 C-30 Dually Pickup 6.2 Turbo Diesel, NP435 ‘72 C-10 SWB , 350 4bbl, TH350 '69 C-10 SWB , 250 L6, 3 OTT '69 GMC C3500, dump truck, 351 V6, NP435 '84 M1009 CUCV Military Blazer 67 C-30 Turbodiesel build thread http://67-72chevytrucks.com/vboard/s...d.php?t=254096 My trucks http://s226.photobucket.com/albums/d...ediafilter=all Member of the 1-Ton Club! Last edited by 67_C-30; 04-20-2008 at 02:14 AM.

04-20-2008, 02:27 AM	#10
msgross Registered User Join Date: Jul 2006 Location: Central PA Posts: 12,201	Re: what is the 4sp manual in a 68 3/4 ton Here is my 465 from the 68 K-10. of course it has a transfer case behind it though.... Attached Images __________________ The Garage: 1968 K-10 SWB - "Project Money Pit" 1996 Z-71 - "huntin rig" 1969 C-10 LWB (SOLD) "Project flip that truck or else" 1993 Passport, F@rd 1-ton (SOLD)"Project Cousin Eddie" My Garage Build "The 1,000 footer"

04-20-2008, 11:00 PM	#11
GMCBubba Registered User Join Date: Oct 2006 Location: Simpsonville, SC Posts: 255	Re: what is the 4sp manual in a 68 3/4 ton no guarantee that the NP 435 is close ratio. i seem to have the np435gl with the super low granny gear. i think. originally came behind a 307. definitely not a drag racing setup. but good for it's original purpose of hauling a bed and trailer full of grain or hay. __________________ 1969 GMC 3/4 ton, 307, 4-speed NP435GL, DANA 60, 4.10, HD rear leafs, manual everything, leaking oil and water. Now rocking 383, NV4500, power steering, power brakes. Finally undergoing restoration.



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