diff replace - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Trucks · 03-04-2004, 10:50 PM

looking for the cheapest way to replace my 4.56 gearing in my 68 GMC 3/4 ton 4x4. I'd like better highway ratios and have never done this. So would you:

get used gears only and have a shop set them up?

go new and have a shop set them up?

get a whole wheel to wheel axle tube used?
(I think I could replace that, I have done rears before)

the main reason for doing this is the rear end grinds over 35 mph I think its got busted teeth, I have to pull the cover yet and see.

DivineFord · 03-04-2004, 11:37 PM

Most likely the cheapest way is to buy new gears and have a shop set them up, unless you are willing to get the tools and information to set the gears up yourself. If you could get the whole replacement axles for your truck for less than a gear swap, go for it. It never hurts to have spares around.

**JIMs70GMC** · 03-05-2004, 06:52 AM

Mac67 is selling a burb w/ 3/4 ton axles. you could swap both axles, get disc up front and higher gears! Remember what ever you do in the rear you have to do up front.

Trucks · 03-05-2004, 01:39 PM

I would be interested, is this burb near Minnesota? Or inexpensive? Which post?

**JIMs70GMC** · 03-05-2004, 03:45 PM

http://67-72chevytrucks.com/vboard/s...threadid=93862

da-burb · 03-05-2004, 09:12 PM

What is inexpensive in your world? The best way that I see doing this is to find a 73+ 3/4 ton or 1 tone 4x4 with the gear ratio you want. I think 3.73's would be the best in this case. You should be able to find a complete truck in the $500 range and even find the parts alone for 2-300. The salvage yards close to the twin cities are over priced for fronts and rears in my opinion. Further out they should be around 100 per ax. A little welding at the local black smithe and off you go!

Trucks · 03-05-2004, 09:45 PM

ya, I'm 1 hr out of the cities to the west, the ones I found they want $300 each for pulled, but that s off another 68. maybe a later model like you said would be cheaper even though I have to have them welded up...what you are quoting sounds like cheap enough to me.

da-burb · 03-06-2004, 02:47 AM

The problem with 67-72 trucks is the best ratio you will find is 4.11's. That's why the 73+ trucks are nice. They were available with 3.73s. I also get a Wisconsin trader mag and they have a fair share of $50-100 14 bolt axles and 4x4 sets for $300. Something to think about anyway.

Trucks · 03-10-2004, 01:29 AM

heres the rear, its grinding when over 35 mph, I need to take the cover off yet and see whats left

da-burb · 03-10-2004, 01:47 AM

You have the dana 60 there. I had a nice 4.11 that would have been a direct bolt in. There are a few 3.54's out there too. Look for a big block truck and you are almost sure to find a Dana 60 3.54 out back.

03-04-2004, 10:50 PM	#1
Trucks Is that a Chevy 69...? Join Date: Feb 2004 Location: Brownton MN Posts: 112	diff replace looking for the cheapest way to replace my 4.56 gearing in my 68 GMC 3/4 ton 4x4. I'd like better highway ratios and have never done this. So would you: get used gears only and have a shop set them up? go new and have a shop set them up? get a whole wheel to wheel axle tube used? (I think I could replace that, I have done rears before) the main reason for doing this is the rear end grinds over 35 mph I think its got busted teeth, I have to pull the cover yet and see. __________________ Ahhhh, the wonderful sound of a rumbling V8.

03-05-2004, 06:52 AM	#3
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	Mac67 is selling a burb w/ 3/4 ton axles. you could swap both axles, get disc up front and higher gears! Remember what ever you do in the rear you have to do up front. __________________ 1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs 1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX 1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears 1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now..... 1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone. 1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed. 1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm

03-05-2004, 01:39 PM	#4
Trucks Is that a Chevy 69...? Join Date: Feb 2004 Location: Brownton MN Posts: 112	thanks I would be interested, is this burb near Minnesota? Or inexpensive? Which post? __________________ Ahhhh, the wonderful sound of a rumbling V8.

03-05-2004, 03:45 PM	#5
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	http://67-72chevytrucks.com/vboard/s...threadid=93862 __________________ 1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs 1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX 1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears 1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now..... 1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone. 1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed. 1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm

03-05-2004, 09:12 PM	#6
da-burb "Ochre Ogre" Join Date: Apr 2000 Location: Springfield, MN Posts: 3,558	What is inexpensive in your world? The best way that I see doing this is to find a 73+ 3/4 ton or 1 tone 4x4 with the gear ratio you want. I think 3.73's would be the best in this case. You should be able to find a complete truck in the $500 range and even find the parts alone for 2-300. The salvage yards close to the twin cities are over priced for fronts and rears in my opinion. Further out they should be around 100 per ax. A little welding at the local black smithe and off you go! __________________ Bowtie Truck Stop Inc. Mid-West GM Truck Restoration Parts Supplier Your Key Parts, Auto Metal Direct, Dynacorn, and Goodmark dealer. like us @ www.facebook.com/BowtieTruckStop 1971 C-10 Suburban (Ochre) 1971 K-10 Suburban (Ochre) 1972 C-10 Suburban (Ochre) 1972 K-20 Suburban (Yellow- that just aint right!) Springfield, Minnesota 56087

03-04-2004, 11:37 PM	#2
DivineFord My Name Is Mudd Join Date: Feb 2004 Location: Bangor, Maine Posts: 101	Most likely the cheapest way is to buy new gears and have a shop set them up, unless you are willing to get the tools and information to set the gears up yourself. If you could get the whole replacement axles for your truck for less than a gear swap, go for it. It never hurts to have spares around.

03-05-2004, 09:45 PM	#7
Trucks Is that a Chevy 69...? Join Date: Feb 2004 Location: Brownton MN Posts: 112	thanks ya, I'm 1 hr out of the cities to the west, the ones I found they want $300 each for pulled, but that s off another 68. maybe a later model like you said would be cheaper even though I have to have them welded up...what you are quoting sounds like cheap enough to me. __________________ Ahhhh, the wonderful sound of a rumbling V8.

03-06-2004, 02:47 AM	#8
da-burb "Ochre Ogre" Join Date: Apr 2000 Location: Springfield, MN Posts: 3,558	The problem with 67-72 trucks is the best ratio you will find is 4.11's. That's why the 73+ trucks are nice. They were available with 3.73s. I also get a Wisconsin trader mag and they have a fair share of $50-100 14 bolt axles and 4x4 sets for $300. Something to think about anyway. __________________ Bowtie Truck Stop Inc. Mid-West GM Truck Restoration Parts Supplier Your Key Parts, Auto Metal Direct, Dynacorn, and Goodmark dealer. like us @ www.facebook.com/BowtieTruckStop 1971 C-10 Suburban (Ochre) 1971 K-10 Suburban (Ochre) 1972 C-10 Suburban (Ochre) 1972 K-20 Suburban (Yellow- that just aint right!) Springfield, Minnesota 56087

03-10-2004, 01:29 AM	#9
Trucks Is that a Chevy 69...? Join Date: Feb 2004 Location: Brownton MN Posts: 112	pics of my diffs heres the rear, its grinding when over 35 mph, I need to take the cover off yet and see whats left Attached Images __________________ Ahhhh, the wonderful sound of a rumbling V8.

03-10-2004, 01:47 AM	#10
da-burb "Ochre Ogre" Join Date: Apr 2000 Location: Springfield, MN Posts: 3,558	You have the dana 60 there. I had a nice 4.11 that would have been a direct bolt in. There are a few 3.54's out there too. Look for a big block truck and you are almost sure to find a Dana 60 3.54 out back. __________________ Bowtie Truck Stop Inc. Mid-West GM Truck Restoration Parts Supplier Your Key Parts, Auto Metal Direct, Dynacorn, and Goodmark dealer. like us @ www.facebook.com/BowtieTruckStop 1971 C-10 Suburban (Ochre) 1971 K-10 Suburban (Ochre) 1972 C-10 Suburban (Ochre) 1972 K-20 Suburban (Yellow- that just aint right!) Springfield, Minnesota 56087



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.