66 GMC What engine?

[67chev"BIG-Bertha"]

Hey everyone, so my wife just bought a 66 GMC. It is a pretty fun truck, and after passing newer vehicles on the freeway, I was loving it, unfortunately I blew a tire about an hour from our house, so I gimped it along to the closest gas station and asked a guy if he had a jack and lug wrench I could borrow since I just bought the truck and didn't have one. Well, I got the spare on and made another half hour and blew the spare. So it sat overnight on the side of the road until I could get it home the next day.
Anyways, we got it home and drove it around a little. We decided to change the oil so I drain the oil and start taking the filter off, and that sucker would not budge. I had the standard filter wrench on there, and it just crinkled up. So I tried pounding a screwdriver through the side to twist it off, and nothing worked, I tried for about a month on and off trying to get it off. Finally, I took the part off that the filter screws to, but I had to basically cut the filter to pieces to get the bolts out. I put the filter in a vice and heated up around the threads and finally got the filter off!!! Next I went to my local NAPA to get the right filter, and after measuring what was left of the old filter, we got a filter that fits. The computer says that the filter for my wifes truck is for older tractors. Needless to say, I am stumped as to what engine this truck has in it. I know it's a V6, and someone told me it is the Big Block V6. I might be stupid, but I had no clue there was such a thing as a Big Block V6. If anyone can help me figure out what engine I have I would appreciate it. I'll try to get a picture of the engine posted on here. Oh yeah, I forgot to mention I believe it is a 3/4 ton truck because it has 8 lug rims.
Thanks everyone.

[Corts60]

You more than likely have a 305D or, if you're lucky, you have a 351. The smallest bore on these engines is 4.25". Basically little coffee cans in there getting slung around. They have a very short stroke and are one of the most reliable engines I have ever owned. They were designed for industrial use and have so many over-engineered parts in them that, besides over-revving, they are indestructable. Check out jolly's site: www.6066gmcguy.org for all the info you ever wanted. Welcome to the V-6 club! Let's get those pics up!

[creep]

Being a 66, it would probably be a 305E. My 63 has a tag on the kickpanel that has the motor, hp, trq, and weight on it. I don't know if 66s had the same thing or not.

[67chev"BIG-Bertha"]

Thanks for your help guys. It's a good running motor, just needs a little tuning and it should run great. Here's a picture, I will take one of the engine.

[67chev"BIG-Bertha"]

Here's a few more pics.

[vin63]

Originally Posted by 67chev"BIG-Bertha"

Here's a few more pics.

That is so damn cool! Nice find.

[Surfdaddy]

Verry nice, and a great engine. When tuned it will run very smooth and will run forever. You will find that the more you look into these engines the more you will like.

[jbgroby]

I love the V-6, You really have to go out of your way to break-em. Like running it a few miles without oil and or water etc.

YOu can click on webshots link to see all the years I've worked on/with one. But this is what they sound like without mufflers.

Start up of GMC 305 V 6 - YouTube

[1Bad62Pro/Street]

1960-1974 GMC Big Block V-6's:
http://www.6066gmcguy.org/
Power ratings & Cubic inches 305Ci-478Ci V6's:
http://6066gmcguy.org/EngineData.htm

1962 GMC 305 V6 Burnout - YouTube

[67chev"BIG-Bertha"]

Thanks a lot guys, I wasn't too sure about it, but now I think I'll stick with it. I really like the way it sounds with those mufflers on it. What kind are they? Also, is there anybody who has a thread about this motor, I'd kinda like to know where to get rebuil kits and stuff like that.

[rustyrodknocker]

thats the truck ive been waiting for.

[Corts60]

Originally Posted by 67chev"BIG-Bertha"

Thanks a lot guys, I wasn't too sure about it, but now I think I'll stick with it. I really like the way it sounds with those mufflers on it. What kind are they? Also, is there anybody who has a thread about this motor, I'd kinda like to know where to get rebuil kits and stuff like that.

www.6066gmcguy.org -all you ever wanted to know about them!

[MusicMan70]

Looks like it has a tach. Is it a sun unit?

[67chev"BIG-Bertha"]

Thanks, It's a good truck. Now the darn clutch is going out or gone out on it. It's all good though. I'm not sure what a sun unit is. What exactly is that. It's probably something I should know, but it's been a long day at work. Thanks again guys.

[Rich 5150 69]

Originally Posted by 67chev"BIG-Bertha"

Thanks, What exactly is that. It's probably something I should know, but it's been a long day at work. Thanks again guys.

Its a tach you never want to part with, everybody looking for them....

[MusicMan70]

It's a Brand name of the Tachometer....

[50bomb]

Cool looking

[67chev"BIG-Bertha"]

Thanks guys, I will have to look at the tach and see if it is a sun tach. So I know this is gonna sound dumb, but does anyone do photoshop and could put some black 18 inch rims on it. I just want to see what it would look like. Thanks guys.

[A.T. RockDriller]

Welcome to your best addiction.

Love your truck.
Rebuild parts are hard to find for these V-sixes, but chances are, you won't ever need any....save for a set of manifold gaskets....or maybe a water pump.

As far as that clutch goes, it's more than likely that ya have a problem with the master or slave cylinder...(they are hydraulic).
You might just need to fill the reservoir...(look closely at the master cylinder, It's a dual purpose set-up) there is a "C" on one side and a "B" on the other.

You probably had that all figured out....but what the heck.

And.....Yes. There are a few PhotoChoppers around.....they usually stay up all night an then sleep all day........

Enjoy that rig....and you can sure get the answers to yer questions if ya hang around this board for a while.

[padresag]

Originally Posted by A.T. RockDriller

Welcome to your best addiction.

Love your truck.
Rebuild parts are hard to find for these V-sixes, but chances are, you won't ever need any....save for a set of manifold gaskets....or maybe a water pump.

As far as that clutch goes, it's more than likely that ya have a problem with the master or slave cylinder...(they are hydraulic).
You might just need to fill the reservoir...(look closely at the master cylinder, It's a dual purpose set-up) there is a "C" on one side and a "B" on the other.

You probably had that all figured out....but what the heck.

And.....Yes. There are a few PhotoChoppers around.....they usually stay up all night an then sleep all day........

Enjoy that rig....and you can sure get the answers to yer questions if ya hang around this board for a while.

60-62 was the years of the hydraulic clutch; same as chevrolet
the GMC does have a different clutch though. more difficult to find. you will be better off to get it rebuilt. just ask on the GMC site and someone will recommend someone close by. there is a decent rebuilder in Oregon I believe
ron

[A.T. RockDriller]

Originally Posted by padresag

60-62 was the years of the hydraulic clutch; same as chevrolet
the GMC does have a different clutch though. more difficult to find. you will be better off to get it rebuilt. just ask on the GMC site and someone will recommend someone close by. there is a decent rebuilder in Oregon I believe
ron

I might be the exception to the rule, Padre, but both my '63's and also my '66 have the hydraulic clutch....
Anyway Bertha..., I'm one of those guys from the '6066 GMC' site....and I sure am available to help if I can...
That spare 351....if it's out of a '67 will be the one ya' want to hang onto.
In '66 and '67 these engines were listed as a performance upgrade by the factory.
It will have a # stamped into the deck right in front of the rt. cylendar head...above the fuel pump that will start with a 351E....serial#.
It is actually one of the Magnum engines with the large intake & exhaust ports an' valves.....for some reason, the factory jes' never actually called it a Magnum.
Should yield 220hp and somewhere close to 370 fp of torque ....as opposed to 165 horsies and around 320 fp or somethin like that.
Pretty cool upgrade for you.
Somewhere on here is a thread with some details on my truck.....had a 305E and stuffed a 351E from a '67 into her....I modified the intake to take a Q-jet....and some other things...I just don't know how to look it up,.....but it's under the title of 'Rockdrillers '63'...
Helluva difference over the others.

BTW....if yer lookin for a machine shop in the Portland area.....which seems a long way from Utah....kinda.....Jerrys Cylinder Head will deal with it for the GMC Vee Sixes..

[padresag]

Originally Posted by A.T. RockDriller

I might be the exception to the rule, Padre, but both my '63's and also my '66 have the hydraulic clutch....
Anyway Bertha..., I'm one of those guys from the '6066 GMC' site....and I sure am available to help if I can...
That spare 351....if it's out of a '67 will be the one ya' want to hang onto.
In '66 and '67 these engines were listed as a performance upgrade by the factory.
It will have a # stamped into the deck right in front of the rt. cylendar head...above the fuel pump that will start with a 351E....serial#.
It is actually one of the Magnum engines with the large intake & exhaust ports an' valves.....for some reason, the factory jes' never actually called it a Magnum.
Should yield 220hp and somewhere close to 370 fp of torque ....as opposed to 165 horsies and around 320 fp or somethin like that.
Pretty cool upgrade for you.
Somewhere on here is a thread with some details on my truck.....had a 305E and stuffed a 351E from a '67 into her....I modified the intake to take a Q-jet....and some other things...I just don't know how to look it up,.....but it's under the title of 'Rockdrillers '63'...
Helluva difference over the others.

BTW....if yer lookin for a machine shop in the Portland area.....which seems a long way from Utah....kinda.....Jerrys Cylinder Head will deal with it for the GMC Vee Sixes..

the hydraulic clutch was used in the 61-62 years due to physical clearances with the x member that was installed with torsion bars. the h/linkage was was applied to the right side of the bell housing. the exception in those years was the "K" series( no x frame) and it may well have also used a h/clutch setup. Don't know!
the frames changed in 63 and light duty went to a mechanical linkage. there was some 62 production carry over(supposedly) into 63 which may be why your 63 4 x 4 has a hydraulic clutch or someone installed it some time.
your 66 is a 4000 series truck . hydraulic clutches were used in larger trucks
seeing as your 63 was a service truck, it may have been ordered that way?????????????
ron

[raylube]

here is some info on the v-6 motors

[Matt's k5]

Hey 1Bad62Pro/Street that's me and my truck right after i got my dual glass packs installed! love these old V6's GMC! How rare is the 351? i got a spare one from a 67 gmc thinking about rebuilding it and putting it in my 62 it has the spin on type filter too, my 305 has the big canister type

[dthela]

You can also try http://www.stovebolt.com for anything you want to know and also parts for sale. Some of the 305's had a filter which takes a cartridge and has a bolt through the bottom through the center to hold it on. Some were also converted to your standard newer type filter. Your engine code is on the front side of the head on the right looking at motor