Rear end swap - The 1947 - Present Chevrolet & GMC Truck Message Board Network

ChadMorris · 03-03-2005, 02:03 PM

OK guys, I could use some more help.....Here are pics of the rear end on my truck.....from what I could tell, I believe it is a 4:56 rear end .....is this right?

I would like to go to something that would run a little better for gas, like something in the mid 3's.........would it be cheaper to put a used rear end or would it be better to replace a set of gears.......

I'm tired of the motor screaming at 50 mph.......

I am also assuming this is a Dana 44, or am I wrong?

thanks for the help

raphyel · 03-04-2005, 01:31 AM

that looks to be a dana rear end, but gears are cheaper if you have someone who will set them cheap for you. the local shop here wants around 200 to do it.

60-66 Nut · 03-04-2005, 10:50 AM

Chad, I was trying to make out the tooth count on the ring gear, but I can't see it. Dana's usually have the ring and pinion tooth count stamped on the ring gear. Divide the ring gear by the pinion and this gives you the ratio; ie 40 tooth ring gear divided by 10 tooth pinion = 4.00:1 ratio. You might end up cheaper finding you another rear end rather than changing gears, especially if you pay someone to set it up. Just wondering, do you know if that's the original rear end? I don't recall seeing a Dana on these trucks. What year and series truck is it?

60-66 Nut

ChadMorris · 03-04-2005, 11:15 AM

It says 46-13 on another pic I have of the main gear, If i am right isn't that the tooth count for the gears? This is a 1964 GMC 1/2 ton........Not the original rear end I know.........Does anyone know what rear end will swap out fairly close....

60-66 Nut · 03-04-2005, 11:55 AM

Chad, if that's the correct tooth count, that comes out to a 3.54:1 ratio which is not too bad. You can mark and count the teeth on the ring and pinion to be sure, but that sounds right. That sure looks like a big rear end for a 1/2 ton truck. How many lugs does it have? As for what will fit right up, I have 66 GMC parts truck, and supposedly the rear end under it comes out of a 79 1/2 ton 4x4 Chevy. It doesn't look like they changed anything else to make it fit, it just looks a little wider from wheel to wheel than the old ones. The 4x4 rear end still has 6 lug wheels like the 66 had. Had you considered an overdrive trans?

60-66 Nut

ChadMorris · 03-04-2005, 12:27 PM

It has six lugs.....I have been looking at Trans' but around north alabama, they want a mint for a trans......and most anything else as far as motors and stuff go......What would be a good OD trans to put in it? besides the 700r4..

64fleetside · 03-04-2005, 12:39 PM

If you're running a six & don't pull loads a bunch a TH200 will work well. Some S10s, Buick Regals, etc use them.Brian

littlee_domn8r · 03-05-2005, 03:20 AM

Quote:

Originally Posted by 60-66 Nut

I don't recall seeing a Dana on these trucks. What year and series truck is it?

60-66 Nut

My 63 GMC 1/2 ton has a dana 44 rear axle. It is the original axle. Mine has a 3.54:1 ratio. I had the ring & pinion and spider gears replaced by a local mechanic. It cost me around $500, but he had to do it twice. He thought the ring & pinion was ok, but it wasn't so I had to pay him to take it all apart again.

tceagent · 03-15-2005, 04:56 PM

Chad,
i have the perfect thing find a rearend from a 70 up automatic.they are usually around the 3:73 to 3:83 range great for Highway use and towing thow if your into et's forget it Rick

03-03-2005, 02:03 PM	#1
ChadMorris Newbie truck Rebuilder! Join Date: Dec 2004 Location: Huntsville, Al Posts: 160	Rear end swap OK guys, I could use some more help.....Here are pics of the rear end on my truck.....from what I could tell, I believe it is a 4:56 rear end .....is this right? I would like to go to something that would run a little better for gas, like something in the mid 3's.........would it be cheaper to put a used rear end or would it be better to replace a set of gears....... I'm tired of the motor screaming at 50 mph....... I am also assuming this is a Dana 44, or am I wrong? thanks for the help __________________ "Old Blue" 1964 GMC Fleetside in pieces 350 TPI with 700R4 tranny now installed( well kinda propped in place until the tranny crossmember is bolted in !!!!! 1995 Toyota 4runner , 197,000 miles and going... 2007 Honda Odyssey Van (Wifes car)

03-04-2005, 01:31 AM	#2
raphyel Registered User Join Date: Aug 2004 Location: Cranston, RI Posts: 162	gears that looks to be a dana rear end, but gears are cheaper if you have someone who will set them cheap for you. the local shop here wants around 200 to do it.

03-04-2005, 10:50 AM	#3
60-66 Nut Professional Beer Tester Join Date: Aug 2004 Location: Louisiana Posts: 453	Chad, I was trying to make out the tooth count on the ring gear, but I can't see it. Dana's usually have the ring and pinion tooth count stamped on the ring gear. Divide the ring gear by the pinion and this gives you the ratio; ie 40 tooth ring gear divided by 10 tooth pinion = 4.00:1 ratio. You might end up cheaper finding you another rear end rather than changing gears, especially if you pay someone to set it up. Just wondering, do you know if that's the original rear end? I don't recall seeing a Dana on these trucks. What year and series truck is it? 60-66 Nut __________________ 60 Ford F100 Custom Cab 61 Apache Short Fleetside 64 C10 Short Stepside 65 C80 409 V8 5spd(X-Firetruck) 83 GMC 350 Olds Diesel 85 GMC Short Bed 86 GMC Short Bed 90 GMC R3500 Crew Cab 92 GMC 1500

03-04-2005, 11:15 AM	#4
ChadMorris Newbie truck Rebuilder! Join Date: Dec 2004 Location: Huntsville, Al Posts: 160	It says 46-13 on another pic I have of the main gear, If i am right isn't that the tooth count for the gears? This is a 1964 GMC 1/2 ton........Not the original rear end I know.........Does anyone know what rear end will swap out fairly close.... __________________ "Old Blue" 1964 GMC Fleetside in pieces 350 TPI with 700R4 tranny now installed( well kinda propped in place until the tranny crossmember is bolted in !!!!! 1995 Toyota 4runner , 197,000 miles and going... 2007 Honda Odyssey Van (Wifes car)

03-04-2005, 11:55 AM	#5
60-66 Nut Professional Beer Tester Join Date: Aug 2004 Location: Louisiana Posts: 453	Chad, if that's the correct tooth count, that comes out to a 3.54:1 ratio which is not too bad. You can mark and count the teeth on the ring and pinion to be sure, but that sounds right. That sure looks like a big rear end for a 1/2 ton truck. How many lugs does it have? As for what will fit right up, I have 66 GMC parts truck, and supposedly the rear end under it comes out of a 79 1/2 ton 4x4 Chevy. It doesn't look like they changed anything else to make it fit, it just looks a little wider from wheel to wheel than the old ones. The 4x4 rear end still has 6 lug wheels like the 66 had. Had you considered an overdrive trans? 60-66 Nut __________________ 60 Ford F100 Custom Cab 61 Apache Short Fleetside 64 C10 Short Stepside 65 C80 409 V8 5spd(X-Firetruck) 83 GMC 350 Olds Diesel 85 GMC Short Bed 86 GMC Short Bed 90 GMC R3500 Crew Cab 92 GMC 1500

03-04-2005, 12:27 PM	#6
ChadMorris Newbie truck Rebuilder! Join Date: Dec 2004 Location: Huntsville, Al Posts: 160	It has six lugs.....I have been looking at Trans' but around north alabama, they want a mint for a trans......and most anything else as far as motors and stuff go......What would be a good OD trans to put in it? besides the 700r4.. __________________ "Old Blue" 1964 GMC Fleetside in pieces 350 TPI with 700R4 tranny now installed( well kinda propped in place until the tranny crossmember is bolted in !!!!! 1995 Toyota 4runner , 197,000 miles and going... 2007 Honda Odyssey Van (Wifes car)

03-04-2005, 12:39 PM	#7
64fleetside Registered User Join Date: Apr 2004 Location: arkieland Posts: 1,070	If you're running a six & don't pull loads a bunch a TH200 will work well. Some S10s, Buick Regals, etc use them.Brian

03-15-2005, 04:56 PM	#9
tceagent Registered User Join Date: Mar 2005 Posts: 16	Reaer end blues? Chad, i have the perfect thing find a rearend from a 70 up automatic.they are usually around the 3:73 to 3:83 range great for Highway use and towing thow if your into et's forget it Rick



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.