68 GMC 4x4 chassis being built to be a 70 4x4! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Patsfan34 · 12-20-2009, 09:15 AM

Well, I'm getting close to having the frame blasted now. Just need to pull t-case, tranny and 292 (which is for sale on the parts forum) and then the real fun begins. Here's a couple pics so I can remember what it looked like as a GMC. From what I've been told the Rockwell T-case is pretty strong, but I don't need to upgrade to the NP205 cause I won't ever be towing or plowing with this truck. I doubt I'll even need to put it in 4WD low! The tranny I think has a granny gear so I may need to get a new tranny for this build cause this truck will be my winter daily driver. I'm swapping out the 292 for a 350 4 bolt with 59K original miles. Let me know what you think and thanks for looking!

292farmer · 12-20-2009, 10:39 AM

nice start, the transmission looks to be a sm465 gear ratios are 1st 6.55:1
2nd 3.57:1 3rd 1.57:1 4th 1:1 reverse 6.05:1 i also sent u pm

Patsfan34 · 12-20-2009, 11:42 AM

Quote:

Originally Posted by 292farmer

nice start, the transmission looks to be a sm465 gear ratios are 1st 6.55:1
2nd 3.57:1 3rd 1.57:1 4th 1:1 reverse 6.05:1 i also sent u pm

I was told that my tranny is a sm420, due to the fact that this specific tranny has the plug directly on the top of the tranny for the reverse lights. But please tell me if that is incorrect cause the more I know the better off I am. And I sent you a PM back, that 292 is for sale on the parts board.

292farmer · 12-20-2009, 11:53 AM

both sm420 and 465 has plug on top at least my 465does i loaded a pic of a sm420 and a sm 465 first pick is sm420 the second sm465 the 465 has those large ribs in the side of the case as yours does and the plug for yours is in same location as the plug in pic of 465 drivers side top in front shifter

Patsfan34 · 12-20-2009, 01:36 PM

292farmer, I just went out to my garage to take a closer look and YOU ARE CORRECT. Thanks for looking out!

BurnoutNova · 12-20-2009, 06:13 PM

I belive the shift pattern will also identify which you have. My 67 had the SM420 and reverse was to the left and down. My 69 K20 and 68 K10 were to the right and down. I was also told that '67 is the only year they used SM420's in out trucks.

Patsfan34 · 12-21-2009, 09:13 AM

Yup, that sounds about right too!

brianthelion02 · 12-21-2009, 12:09 PM

Unless you just want to stay original,i would be on the lookout for a replaement for the rockwell t-case!I know they are bulletproof which is somewhat their downfall.They have straight cut gears in them which makes them fairly noisy! If you are building a cruiser you probably wont like tha much! My 69 k-20's rockwell drove me nuts!Dang thing sounded like a jet airplane takin off at 30 mph plus!!LOL

Patsfan34 · 12-21-2009, 01:07 PM

Quote:

Originally Posted by brianthelion02

Unless you just want to stay original,i would be on the lookout for a replaement for the rockwell t-case!I know they are bulletproof which is somewhat their downfall.They have straight cut gears in them which makes them fairly noisy! If you are building a cruiser you probably wont like tha much! My 69 k-20's rockwell drove me nuts!Dang thing sounded like a jet airplane takin off at 30 mph plus!!LOL

Well, I really didn't want to spend any money on another T-case. I was going to have this one inspection, and if no problems was going to throw right back in. What are rebuilt NP205s going for these days? And yes I'm just building a cruiser!

brianthelion02 · 12-21-2009, 01:47 PM

Since you have it i would go ahead and run it,but if you see somethin else within grasp,id grab it,lol!! I pulled my sm-465 and put in a 700r4 with a np241 behind it!Love the 3 mpg it gained me and the ability to cruise at 75 mph with no problems!Also nice and quiet!You might ask around those who are running the rockwell!I thought somethin was wrong with mine but was told by several people that was a side affect of having the super strong straight cut gears!

**wancosc356** · 12-21-2009, 08:46 PM

So thats what it looked like yesterday. I assume you already got it disassembled and its at the blasters now...right! haha. Just messing with ya man. Can't wait to see this one come together.

Patsfan34 · 12-23-2009, 11:09 AM

Quote:

Originally Posted by wancosc356

So thats what it looked like yesterday. I assume you already got it disassembled and its at the blasters now...right! haha. Just messing with ya man. Can't wait to see this one come together.

The funny thing is the more I get into this build the more I keep changing my mind on things. But I still can't wait to be finished!

**wancosc356** · 12-23-2009, 01:28 PM

Quote:

Originally Posted by Patsfan34

The funny thing is the more I get into this build the more I keep changing my mind on things. But I still can't wait to be finished!

That's how it goes. I keep adding and subtracting from my build plans every day. And I haven't even started. Haha.

msgross · 12-23-2009, 01:46 PM

If you are going to use it as a daily driver, and want a manual shift tranny then I suggest an NV4500 woth an NP205 adapted to it.

Rockwell and 205 are both gear driver, rockwell is noisy and parts aren't cheap... 205 parts are cheap and very common...

the NV4500 is a five speed tranny which will make for a nicer driver.

check out Rust Buster and Musclerodz build threads for this setup...

I'm gonna move this over to the 4x4 builds...

mstrav1973 · 12-24-2009, 03:57 PM

you will find as I have / did, that the design and intent of your build will evolve as you progress. I had so many things set in stone, and then later go a total dif route after getting more ideas.

I am showing you a pic of my frame last november when I started to help inspire you.

Matt

mstrav1973 · 12-24-2009, 03:58 PM

heres this last october

Matt

Patsfan34 · 12-26-2009, 07:02 PM

msgross, I'm thinking that I will probably go with that drive train setup. Now I'll just need to find that stuff or hope someone will do a trade.

mstrav, nice work man. Those pics give me something to look forward too!

litebulblsc · 12-26-2009, 07:07 PM

Does anyone else thing that the tcase looks like a 205?

Patsfan34 · 12-26-2009, 07:56 PM

Quote:

Originally Posted by litebulblsc

Does anyone else thing that the tcase looks like a 205?

That I'm positive about. Its a rockwell, you can tell by the linkage and also it still has the name plate right on top of the T-case.

Patsfan34 · 12-27-2009, 07:26 PM

Donor body, well sort of. I just sold the bed today to shortbedbob, but I'm using the cab and some of the front clip and definitely the engine.

Conroe trucker · 12-28-2009, 01:01 PM

You might sriously consider keeping the 292.

They run forever, and are cheap to rebuild.
The amount of torque you get at low RPM is matched only by a big block.

And, you are not like everyone else.

Problems are low RPM make it a low speed car.
I top out around 55 MPH, but hey, it was never built to go fast was it?

Mike

**Yukon Jack** · 12-28-2009, 06:16 PM

Just keep an eye on the level of the Rockwell's gear oil and you will be fine. The are a bit louder than an NP205 but not loud enough to be a major issue IMO. An NP205 with the correct adapter to mate to your SM465 will run between $200 to $400, at least around Kansas.

Patsfan34 · 12-30-2009, 06:33 PM

Quote:

Originally Posted by Yukon Jack

Just keep an eye on the level of the Rockwell's gear oil and you will be fine. The are a bit louder than an NP205 but not loud enough to be a major issue IMO. An NP205 with the correct adapter to mate to your SM465 will run between $200 to $400, at least around Kansas.

I'm up in the air about switching. I think it will all depend on the condition of the rockwell when I break it open. If its in good shape and doesn't need an overhaul, I'll use it. If it's trashed I'll probably upgrade to the setup msgross suggested. Thanks for the look Jack!

my67chevytruck · 12-31-2009, 02:06 AM

subscribed... just picked up a 69 k10 roller and will need ideas/inspiration......

vk_chevy · 01-09-2010, 01:51 AM

this is a cool build,

12-20-2009, 09:15 AM	#1
Patsfan34 Registered User Join Date: Dec 2008 Location: New England Posts: 661	68 GMC 4x4 chassis being built to be a 70 4x4! Well, I'm getting close to having the frame blasted now. Just need to pull t-case, tranny and 292 (which is for sale on the parts forum) and then the real fun begins. Here's a couple pics so I can remember what it looked like as a GMC. From what I've been told the Rockwell T-case is pretty strong, but I don't need to upgrade to the NP205 cause I won't ever be towing or plowing with this truck. I doubt I'll even need to put it in 4WD low! The tranny I think has a granny gear so I may need to get a new tranny for this build cause this truck will be my winter daily driver. I'm swapping out the 292 for a 350 4 bolt with 59K original miles. Let me know what you think and thanks for looking! Attached Images

12-20-2009, 10:39 AM	#2
292farmer Registered User Join Date: Nov 2009 Location: stoddard nh Posts: 693	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! nice start, the transmission looks to be a sm465 gear ratios are 1st 6.55:1 2nd 3.57:1 3rd 1.57:1 4th 1:1 reverse 6.05:1 i also sent u pm

12-20-2009, 11:53 AM	#4
292farmer Registered User Join Date: Nov 2009 Location: stoddard nh Posts: 693	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! both sm420 and 465 has plug on top at least my 465does i loaded a pic of a sm420 and a sm 465 first pick is sm420 the second sm465 the 465 has those large ribs in the side of the case as yours does and the plug for yours is in same location as the plug in pic of 465 drivers side top in front shifter Attached Images Last edited by 292farmer; 12-20-2009 at 11:55 AM.

12-20-2009, 01:36 PM	#5
Patsfan34 Registered User Join Date: Dec 2008 Location: New England Posts: 661	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! 292farmer, I just went out to my garage to take a closer look and YOU ARE CORRECT. Thanks for looking out!

12-20-2009, 06:13 PM	#6
BurnoutNova Registered User Join Date: Mar 2004 Location: CA Posts: 2,057	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! I belive the shift pattern will also identify which you have. My 67 had the SM420 and reverse was to the left and down. My 69 K20 and 68 K10 were to the right and down. I was also told that '67 is the only year they used SM420's in out trucks.

12-21-2009, 09:13 AM	#7
Patsfan34 Registered User Join Date: Dec 2008 Location: New England Posts: 661	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! Yup, that sounds about right too!

12-21-2009, 12:09 PM	#8
brianthelion02 Overdrive club Join Date: Sep 2007 Location: apache junction, arizona Posts: 819	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! Unless you just want to stay original,i would be on the lookout for a replaement for the rockwell t-case!I know they are bulletproof which is somewhat their downfall.They have straight cut gears in them which makes them fairly noisy! If you are building a cruiser you probably wont like tha much! My 69 k-20's rockwell drove me nuts!Dang thing sounded like a jet airplane takin off at 30 mph plus!!LOL __________________ 1971 c-10 1951 3100 chevy 1970 chevy c-30 Sold!

12-21-2009, 01:47 PM	#10
brianthelion02 Overdrive club Join Date: Sep 2007 Location: apache junction, arizona Posts: 819	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! Since you have it i would go ahead and run it,but if you see somethin else within grasp,id grab it,lol!! I pulled my sm-465 and put in a 700r4 with a np241 behind it!Love the 3 mpg it gained me and the ability to cruise at 75 mph with no problems!Also nice and quiet!You might ask around those who are running the rockwell!I thought somethin was wrong with mine but was told by several people that was a side affect of having the super strong straight cut gears! __________________ 1971 c-10 1951 3100 chevy 1970 chevy c-30 Sold!

12-21-2009, 08:46 PM	#11
wancosc356 I Like Mine With No Shine! Join Date: Apr 2009 Location: SC Posts: 2,705	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! So thats what it looked like yesterday. I assume you already got it disassembled and its at the blasters now...right! haha. Just messing with ya man. Can't wait to see this one come together. __________________ Michael 1967 Chevrolet C10 Short Fleet (Literal Ground Up....One Day) 2006 GMC Sierra Crew Cab 4x4 1969 Lincoln Continental Coupe Project FOR SALE http://67-72chevytrucks.com/vboard/c...ct=4578&cat=17 1981 Honda CM400 C Bobber SOLD http://67-72chevytrucks.com/vboard/s...d.php?t=384152

12-23-2009, 01:46 PM	#14
msgross Registered User Join Date: Jul 2006 Location: Central PA Posts: 12,201	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! If you are going to use it as a daily driver, and want a manual shift tranny then I suggest an NV4500 woth an NP205 adapted to it. Rockwell and 205 are both gear driver, rockwell is noisy and parts aren't cheap... 205 parts are cheap and very common... the NV4500 is a five speed tranny which will make for a nicer driver. check out Rust Buster and Musclerodz build threads for this setup... I'm gonna move this over to the 4x4 builds... __________________ 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"

12-24-2009, 03:57 PM	#15
mstrav1973 Registered User Join Date: Oct 2008 Location: Meridian, Idaho Posts: 321	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! you will find as I have / did, that the design and intent of your build will evolve as you progress. I had so many things set in stone, and then later go a total dif route after getting more ideas. I am showing you a pic of my frame last november when I started to help inspire you. Matt Attached Images __________________ 72 chevy k-10, swb, auto, 35's, rally's, posi, 4" lift, 2.5" old style 40 series flows with headers and crossover pipe and some other stuff!!

12-24-2009, 03:58 PM	#16
mstrav1973 Registered User Join Date: Oct 2008 Location: Meridian, Idaho Posts: 321	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! heres this last october Matt Attached Images __________________ 72 chevy k-10, swb, auto, 35's, rally's, posi, 4" lift, 2.5" old style 40 series flows with headers and crossover pipe and some other stuff!!

12-26-2009, 07:02 PM	#17
Patsfan34 Registered User Join Date: Dec 2008 Location: New England Posts: 661	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! msgross, I'm thinking that I will probably go with that drive train setup. Now I'll just need to find that stuff or hope someone will do a trade. mstrav, nice work man. Those pics give me something to look forward too!

12-26-2009, 07:07 PM	#18
litebulblsc Registered User Join Date: Aug 2006 Location: LaSalle Mi Posts: 525	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! Does anyone else thing that the tcase looks like a 205?

12-27-2009, 07:26 PM	#20
Patsfan34 Registered User Join Date: Dec 2008 Location: New England Posts: 661	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! Donor body, well sort of. I just sold the bed today to shortbedbob, but I'm using the cab and some of the front clip and definitely the engine. Attached Images



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12-28-2009, 01:01 PM	#21
Conroe trucker SWBs: 67 2x4, 67 4x4, 70 4x4 Join Date: Nov 2007 Location: Conroe, TX Posts: 483	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! You might sriously consider keeping the 292. They run forever, and are cheap to rebuild. The amount of torque you get at low RPM is matched only by a big block. And, you are not like everyone else. Problems are low RPM make it a low speed car. I top out around 55 MPH, but hey, it was never built to go fast was it? Mike __________________ FINISHED Project thread: 67 SWB 4x4 FINISHED Project thread: 67 SWB 6 cyl cruiser Project thread: Road Toad 70 SWB Step, 4x4, 292, 3OT 01 C5 convertable 08 Z06

12-28-2009, 06:16 PM	#22
Yukon Jack Post Whore Join Date: Feb 2000 Location: Rose Hill, KS, USA Posts: 12,686	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! Just keep an eye on the level of the Rockwell's gear oil and you will be fine. The are a bit louder than an NP205 but not loud enough to be a major issue IMO. An NP205 with the correct adapter to mate to your SM465 will run between $200 to $400, at least around Kansas. __________________ 1970 Blazer with a 400 sbc and 4" lift 1980 Pontiac Trans Am, 455 Oldsmobile 2012 Kawasaki Concours 14

12-31-2009, 02:06 AM	#24
my67chevytruck Under Construction Join Date: Oct 2007 Location: Midlothian,TX (DFW) Posts: 4,555	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! subscribed... just picked up a 69 k10 roller and will need ideas/inspiration...... __________________ Heath subscribe to the board here: http://67-72chevytrucks.com/vboard/payments.php http://67-72chevytrucks.com/vboard/s...d.php?t=157669 FAQ how to's 1956 Chevy Apache 1967 C10 SWB FleetSide (under construction) 1969 K10 SWB FleetSide (Future Build) 1972 C10 SWB Stepside (Future Build) 56 chevy truck : http://www.cardomain.com/ride/2955823/1 67 truck build: http://www.67-72chevytrucks.com/vboard/showthread.php?t=281357/1 69 k10: http://67-72chevytrucks.com/vboard/s...d.php?t=389470

01-09-2010, 01:51 AM	#25
vk_chevy Registered User Join Date: Jan 2004 Location: Olympia, WA Posts: 231	Re: 68 GMC 4x4 chassis being built to be a 70 4x4! this is a cool build, __________________ 72 Chevy C20 Longhorn 72 Chevy, K20 Custom Camper 67 Chevy, LWB, C20, 350/350, PS, PB, 65 Jag MKII

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