just purchased a 68 gmc have a few questions - The 1947 - Present Chevrolet & GMC Truck Message Board Network

68jimmy · 12-03-2003, 02:50 AM

hello all. This past weekend I picked up a 68 gmc lwb 3/4 that is in great shape! It came equipped with the 351C V-6 with a three speed (was three on the tree but converted to a floor shift) and power assisted brakes (drums sadly). Now that you know what I have here is what I want to do:

1. convert the front-end to have power-assist disk brakes, power steering and five-lug bolt pattern. From what I've read so far a cross member from a 73-80 should do the trick?

2. replace the heavy rear leaf springs with some from a 1/2 ton. What year of chassis do I need to take care of this?

3. replace the rear differential (dana 60?) to what? and from where?

4. replace the original three speed with a four speed but not one with the granny gear. any ideas here?

5 and finally what do I do about that split drive shaft? do I wait until I get that four speed and differential swapped to get a better idea?

From all I have read so far there seems to be some very creative folks out there... Any help appreciated!

donovan

mikep684x4 · 12-03-2003, 03:05 AM

1) With a little shim stock the a arm front from 73 up fits good

2)You should try to find leavs from our year trucks because the73 up models are longer.

3)My brother took axels (5 lug)from a lte model truck and swapped them in a early 12 bolt rearend.

4)If you want a 4 with out the granny,well I'm not sure,the other guys here know witch one you need but I've found a 90-95 5 speed fit pretty good.

5)yes I would wait till you get your setup together before your set your mind on a driveline.
Hope this helps

68jimmy · 12-03-2003, 03:22 AM

When you indicated with a few shims the 73 a-arms would fit, did you mean just the arms or the entire crossmember?

thanks...

mikep684x4 · 12-03-2003, 03:30 AM

The whole crossmember will bolt in but you are left with a little gap between the a arms and the frame. Alittle is like a 1/16 or so.you want to shim it so it fits tight,and won't tweak your frame when you snug it down.

68jimmy · 12-03-2003, 03:36 AM

thats helpful to know...

thanks again...

krue · 12-03-2003, 08:21 AM

Welcome to the board from South Mississippi!

With a LWB you are probably stuck with a two piece drive shaft unless you want to spend some major money.

*dtlilly* · 12-03-2003, 04:05 PM

Welcome to the board from Tennessee. Let's see some pics

Custom 68 · 12-03-2003, 04:44 PM

I would like to expand on a question for myself. I too just purchased a 69 GMC 3/4 but mine is a 4x4 what can I do for disk front brakes on this. I believe I would want to keep the 8 lug. It just looks tougher

**Yukon Jack** · 12-03-2003, 04:53 PM

Custom 68, I believe starting in 1970 you can find disks on the 3/4 ton front axles. They are a direct bolt in. Try to get one like from a late 70's as those Dana 44's were stronger. If you got lucky you could score a Dana 60 (1 ton front axle) but they aren't the easiest to find. Still an easy swap if you find one.

Suicide-D · 12-03-2003, 08:19 PM

No mention of ripping out the v-6 and sticking in a small block. It's good to be different

68jimmy · 12-03-2003, 11:42 PM

I've always liked doing things a bit different than everyone else. And I like the looks on the parts guy face when I tell them I have a 350 V6!

Longhorn Man · 12-04-2003, 12:57 AM

The 351 is a kick @ss engine...pull anything you hook up to.
You'll want to look at your bellhousing shape and bolt pattern. The question has come up before, and I'm not sure how it came out as in is it a chevy bellhousing, a BOP...or something weird.
The 2 pc shaft is fine. just install good components, and it'll last a long time. To do a 1 pc properly will cost you more than you'd ever want to spend. Most shops wouldn't even touch that, and 1/2 the ones that would...shouldn't.
Welcome to the board. If you have not seen this site on the V-6...you need to read it. Tons of awsome info on there. http://www.6066gmctrucks.org/305V6.htm

1969 GMC · 12-04-2003, 03:43 AM

351 V6...sweet! You don't usually see too many 305 V6 trucks, and yours is the first i've heard of with the 351. got any pics of the glovebox sticker?

68jimmy · 12-04-2003, 08:29 PM

Unfortunatley no sticker in the glove box, and I wish I could get a good picture of the block where the markings are... Anyway here are a few pictures that I took earlier today.

68jimmy · 12-04-2003, 08:30 PM

68jimmy · 12-04-2003, 08:35 PM

351 V6

**Canadian694x4** · 12-04-2003, 10:16 PM

Nice truck! very nice V-6 too!

12-03-2003, 02:50 AM	#1
68jimmy Registered User Join Date: Dec 2003 Location: albuquerque Posts: 431	just purchased a 68 gmc have a few questions hello all. This past weekend I picked up a 68 gmc lwb 3/4 that is in great shape! It came equipped with the 351C V-6 with a three speed (was three on the tree but converted to a floor shift) and power assisted brakes (drums sadly). Now that you know what I have here is what I want to do: 1. convert the front-end to have power-assist disk brakes, power steering and five-lug bolt pattern. From what I've read so far a cross member from a 73-80 should do the trick? 2. replace the heavy rear leaf springs with some from a 1/2 ton. What year of chassis do I need to take care of this? 3. replace the rear differential (dana 60?) to what? and from where? 4. replace the original three speed with a four speed but not one with the granny gear. any ideas here? 5 and finally what do I do about that split drive shaft? do I wait until I get that four speed and differential swapped to get a better idea? From all I have read so far there seems to be some very creative folks out there... Any help appreciated! donovan

12-03-2003, 03:05 AM	#2
mikep684x4 Seeker of the big and bad Join Date: Nov 2000 Location: wheatland,Calif,yuba Posts: 105	1) With a little shim stock the a arm front from 73 up fits good 2)You should try to find leavs from our year trucks because the73 up models are longer. 3)My brother took axels (5 lug)from a lte model truck and swapped them in a early 12 bolt rearend. 4)If you want a 4 with out the granny,well I'm not sure,the other guys here know witch one you need but I've found a 90-95 5 speed fit pretty good. 5)yes I would wait till you get your setup together before your set your mind on a driveline. Hope this helps __________________ 71 3/4 ton 4x4,665hp 454. 67 GMC 1 ton towtruck 68 chevy LB 4x4 64 chevy LB custom 57 Bel-air 2d station wagon

12-03-2003, 03:30 AM	#4
mikep684x4 Seeker of the big and bad Join Date: Nov 2000 Location: wheatland,Calif,yuba Posts: 105	The whole crossmember will bolt in but you are left with a little gap between the a arms and the frame. Alittle is like a 1/16 or so.you want to shim it so it fits tight,and won't tweak your frame when you snug it down. __________________ 71 3/4 ton 4x4,665hp 454. 67 GMC 1 ton towtruck 68 chevy LB 4x4 64 chevy LB custom 57 Bel-air 2d station wagon

12-03-2003, 08:21 AM	#6
krue Designated A-hole! Join Date: Mar 2003 Location: South Mississippi Posts: 36,448	Welcome to the board from South Mississippi! With a LWB you are probably stuck with a two piece drive shaft unless you want to spend some major money. __________________ "If it ain't broke, fix it 'til it is!" Being stupid ain't illegal. We're Still Debt Free Except for the House!!! www.daveramsey.com 70 GMC SWB Stepside project "Green Booger" soon to be 6.0l/4l80e 93 S-10 "Poppaw's Truck"

12-03-2003, 04:44 PM	#8
Custom 68 Registered User Join Date: Nov 2001 Location: Springfield, MO Posts: 2,939	yes welcome I would like to expand on a question for myself. I too just purchased a 69 GMC 3/4 but mine is a 4x4 what can I do for disk front brakes on this. I believe I would want to keep the 8 lug. It just looks tougher __________________ Dave 1968 Custom Chevy with turbo charged 5.3 gen III 4l80e swap 1967-71 GMC 3/4 ton long step 4x4 (not sure what year exactly?) "A good friend will bail you out of jail...but a true friend will be sitting next to you saying "that was frekin awesome". "If it doesn't fit force it...If it breaks then it needed to be replaced anyway!"

12-03-2003, 03:22 AM	#3
68jimmy Registered User Join Date: Dec 2003 Location: albuquerque Posts: 431	When you indicated with a few shims the 73 a-arms would fit, did you mean just the arms or the entire crossmember? thanks...

12-03-2003, 03:36 AM	#5
68jimmy Registered User Join Date: Dec 2003 Location: albuquerque Posts: 431	thats helpful to know... thanks again...

12-03-2003, 04:05 PM	#7
dtlilly Account Suspended Join Date: Jan 2003 Location: Shadow of Lambeau Field Posts: 5,597	Welcome to the board from Tennessee. Let's see some pics

12-03-2003, 04:53 PM	#9
Yukon Jack Post Whore Join Date: Feb 2000 Location: Rose Hill, KS, USA Posts: 12,686	Custom 68, I believe starting in 1970 you can find disks on the 3/4 ton front axles. They are a direct bolt in. Try to get one like from a late 70's as those Dana 44's were stronger. If you got lucky you could score a Dana 60 (1 ton front axle) but they aren't the easiest to find. Still an easy swap if you find one. __________________ 1970 Blazer with a 400 sbc and 4" lift 1980 Pontiac Trans Am, 455 Oldsmobile 2012 Kawasaki Concours 14

12-03-2003, 08:19 PM	#10
Suicide-D Registered User Join Date: Jan 2001 Location: Katy, TX...but the love of my life resides in Dublin,OH. Posts: 1,408	I'm shocked No mention of ripping out the v-6 and sticking in a small block. It's good to be different

12-03-2003, 11:42 PM	#11
68jimmy Registered User Join Date: Dec 2003 Location: albuquerque Posts: 431	I've always liked doing things a bit different than everyone else. And I like the looks on the parts guy face when I tell them I have a 350 V6!

12-04-2003, 12:57 AM	#12
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	The 351 is a kick @ss engine...pull anything you hook up to. You'll want to look at your bellhousing shape and bolt pattern. The question has come up before, and I'm not sure how it came out as in is it a chevy bellhousing, a BOP...or something weird. The 2 pc shaft is fine. just install good components, and it'll last a long time. To do a 1 pc properly will cost you more than you'd ever want to spend. Most shops wouldn't even touch that, and 1/2 the ones that would...shouldn't. Welcome to the board. If you have not seen this site on the V-6...you need to read it. Tons of awsome info on there. http://www.6066gmctrucks.org/305V6.htm

12-04-2003, 03:43 AM	#13
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	351 V6...sweet! You don't usually see too many 305 V6 trucks, and yours is the first i've heard of with the 351. got any pics of the glovebox sticker? __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650

12-04-2003, 08:29 PM	#14
68jimmy Registered User Join Date: Dec 2003 Location: albuquerque Posts: 431	Some Pics Unfortunatley no sticker in the glove box, and I wish I could get a good picture of the block where the markings are... Anyway here are a few pictures that I took earlier today. Attached Images

12-04-2003, 08:30 PM	#15
68jimmy Registered User Join Date: Dec 2003 Location: albuquerque Posts: 431	Attached Images



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12-04-2003, 08:35 PM	#16
68jimmy Registered User Join Date: Dec 2003 Location: albuquerque Posts: 431	351 V6 Attached Images

12-04-2003, 10:16 PM	#17
Canadian694x4 Born To Lose Club Join Date: Feb 2003 Location: Calgary, Alberta/Oxenden, Ontario, Great White North Posts: 13,307	Nice truck! very nice V-6 too! __________________ Brian Smith - "Born To Lose" 1969 Chevrolet K10 LWB Fleetside - Proud Owner For 22 Yrs - 1 of 208 Built & Sold In Canada!- 283 V8/350TH/NP208, 2" All Spring Lift, 32" Good Year MT/R's. 1972 GMC K2500 Custom LWB Fleetside - Proud Owner For 3 Yrs - 1 of 571 Built & Sold In Canada! - 350 V8/SM465/NP205, 4” Rough Country Lift, 33” Interco TSL Thornbirds 2007.5 GMC Sierra SLE 2500HD 4x4 - Proud Owner For 17 Yrs- 6.6L V8 Duramax Diesel/Allison 1000, 2" Lift, 33" Mickey Thompson MTZ's. 2008 Yamaha Raptor 700r - Proud Owner For 15 Yrs - ITP Mud Lites. 2015 John Deere 1025R - Proud Owner For 8 Yrs - 24HP Diesel/H120/54D/260B/SB1154.

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