'71 C-20 Rear Axle ID????? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

TP from Cntl PA · 08-09-2005, 03:10 PM

I seen it on here before, but can't seem to find it now..............How do I ID my rear axle, It isn't a Dana, but how do I know which of the other ones put in these truck is under it? How many did they offer for the 3/4 tons? What ratios can be had? I should put a Dana 60 under it, but winter will be here quick and I need the truck to haul wood and wagons on the farm for harvest.

I need a lower set of rear end gears. First gear is to high for the weight we are tugging with my truck off-road, and the engine wants to GO no matter what.........

Robert1970C20rstbukt · 08-09-2005, 03:36 PM

It's probably the eaton/corporate HO52. The only gears you can get for 'em is 4.11's, 4.57's, and 5.14's. Are you running an auto or stick shift?

**JIMs70GMC** · 08-09-2005, 03:59 PM

It's a corporate rear axle, eaton stye: has a drop out center section. Designated H052 like Robert said. The H072 was in the 1 ton trucks and has a bolt on the side to minimize ring gear deflection. H072s in a 1 ton cab and chassis (dually) were rated at 11000lbs(from the label plate on the 72 C30 I sold to Randy).
Easy to swap gears just find a center section w/ the gears you need. My Chevy has 4.57s w/ the SM465 tranny I have no problem starting in 3rd gear w/ 35" tires!

If you have 4.11s I'll trade you a 4.56s open center section I have in my garage.

TP from Cntl PA · 08-09-2005, 05:48 PM

Yes, it is an Eaton Style, but I don't know what model.............The center section is different, might be a transplant out of a one ton(I got my '69 GMC 1-ton buried in the shed with tractors or I'd compare it)..........I'll take a picture of it.

I don't know what ratio is currently in it, but I am going to find out. It must be a 4.11 because it is gear fairly high, I thought you could also get something like a 3.54 in them too? Close to the 3.73's in our 1/2 tons.

I am running a stock 3spd with a 3spd OD unit behind it for 10 spds total, Works great, other than the fact the first gear isn't low enough. I thought about swapping in a 4 spd, but like how these 3spds shift with a good floor shifter and I don't really want to hack the cab up(Low hump).........It would be easier for me to swap in lower rear end gears, as I have plenty of OD speeds to use.

**JIMs70GMC** · 08-09-2005, 06:01 PM

3.54s came in the dana60s in the 3/4 tons. 4.11 is the highest in the eaton. It's not too hard to do the floor, I cut the low hump out of my Chevy(was a 2wd auto) and bolted in the high hump out of the 4wd 4spd cab. The H052 and H072 look identical except for the bolt on the side. I'd take some pics if it wasn't raining, have an H052 in the Chevy as well as a H072 center and a dually rear(H072). I have a dana60 w/o gears also w/ carrier.

TP from Cntl PA · 08-09-2005, 06:12 PM

Quote:

Originally Posted by JIMs70GMC

3.54s came in the dana60s in the 3/4 tons. 4.11 is the highest in the eaton. The H052 and H072 look identical except for the bolt on the side. I'd take some pics if it wasn't raining, have an H052 in the Chevy as well as a H072 center and a dually rear(H072). I have a dana60 w/o gears also w/ carrier.

Ok, knew I seen 3.54's and 3/4 ton in the same line somewhere

It must be 4.11's then.............I'll take a picture of the center section and post it here tonight.

Yes, I could easily put a high hump in the truck, but I don't like hacking anything up that I can't put back the way it came new.........

TP from Cntl PA · 08-09-2005, 07:00 PM

Here is a picture(Hopefully) of the center section...............Which model is it?

Longhorn Man · 08-09-2005, 07:38 PM

red x here...and tried going to the picture's URL and I was not permitted to look at it.

crew70 · 08-09-2005, 07:57 PM

I have had several HO52 and mine now has the bolt on the side. only dif I have seen is brake size.

**JIMs70GMC** · 08-09-2005, 07:59 PM

That's true everything I've seen shows the biggest difference between the two(H052/H072) is the size of the brakes.

08-09-2005, 03:10 PM	#1
TP from Cntl PA Registered User Join Date: Apr 2003 Location: Central PA....In the Berg of Nisbet Posts: 790	'71 C-20 Rear Axle ID????? I seen it on here before, but can't seem to find it now..............How do I ID my rear axle, It isn't a Dana, but how do I know which of the other ones put in these truck is under it? How many did they offer for the 3/4 tons? What ratios can be had? I should put a Dana 60 under it, but winter will be here quick and I need the truck to haul wood and wagons on the farm for harvest. I need a lower set of rear end gears. First gear is to high for the weight we are tugging with my truck off-road, and the engine wants to GO no matter what......... __________________ '72 K-20 EFI'ed 250 Inline/4spd stake body, Farm Truck '71 C-20 Cummins Diesel Powered, In storage thanks to $5.00 diesel! '69 3500 GMC 305V-6/4spd, Still under reconstruction.......... Inlines Rule! 6 soldiers standing is better than 8 laying down!!!!!!!!

08-09-2005, 03:36 PM	#2
Robert1970C20rstbukt Registered User Join Date: Jun 2004 Location: Beeville, Texas Posts: 1,943	It's probably the eaton/corporate HO52. The only gears you can get for 'em is 4.11's, 4.57's, and 5.14's. Are you running an auto or stick shift? __________________ RJD 1984 Chevrolet C30 welding truck 454/SM465 1977 GMC C15 pickup 350/TH350 1970 Chevrolet C20 pickup 350/TH400 1970 Chevrolet K20 Suburban 454/TH350 1969 GMC 8500 478M V6/5 spd winch truck

08-09-2005, 03:59 PM	#3
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	It's a corporate rear axle, eaton stye: has a drop out center section. Designated H052 like Robert said. The H072 was in the 1 ton trucks and has a bolt on the side to minimize ring gear deflection. H072s in a 1 ton cab and chassis (dually) were rated at 11000lbs(from the label plate on the 72 C30 I sold to Randy). Easy to swap gears just find a center section w/ the gears you need. My Chevy has 4.57s w/ the SM465 tranny I have no problem starting in 3rd gear w/ 35" tires! If you have 4.11s I'll trade you a 4.56s open center section I have in my garage. __________________ 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 Last edited by JIMs70GMC; 08-09-2005 at 04:00 PM.

08-09-2005, 05:48 PM	#4
TP from Cntl PA Registered User Join Date: Apr 2003 Location: Central PA....In the Berg of Nisbet Posts: 790	Yes, it is an Eaton Style, but I don't know what model.............The center section is different, might be a transplant out of a one ton(I got my '69 GMC 1-ton buried in the shed with tractors or I'd compare it)..........I'll take a picture of it. I don't know what ratio is currently in it, but I am going to find out. It must be a 4.11 because it is gear fairly high, I thought you could also get something like a 3.54 in them too? Close to the 3.73's in our 1/2 tons. I am running a stock 3spd with a 3spd OD unit behind it for 10 spds total, Works great, other than the fact the first gear isn't low enough. I thought about swapping in a 4 spd, but like how these 3spds shift with a good floor shifter and I don't really want to hack the cab up(Low hump).........It would be easier for me to swap in lower rear end gears, as I have plenty of OD speeds to use. __________________ '72 K-20 EFI'ed 250 Inline/4spd stake body, Farm Truck '71 C-20 Cummins Diesel Powered, In storage thanks to $5.00 diesel! '69 3500 GMC 305V-6/4spd, Still under reconstruction.......... Inlines Rule! 6 soldiers standing is better than 8 laying down!!!!!!!!

08-09-2005, 06:01 PM	#5
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	3.54s came in the dana60s in the 3/4 tons. 4.11 is the highest in the eaton. It's not too hard to do the floor, I cut the low hump out of my Chevy(was a 2wd auto) and bolted in the high hump out of the 4wd 4spd cab. The H052 and H072 look identical except for the bolt on the side. I'd take some pics if it wasn't raining, have an H052 in the Chevy as well as a H072 center and a dually rear(H072). I have a dana60 w/o gears also w/ carrier. __________________ 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

08-09-2005, 07:00 PM	#7
TP from Cntl PA Registered User Join Date: Apr 2003 Location: Central PA....In the Berg of Nisbet Posts: 790	Here is a picture(Hopefully) of the center section...............Which model is it? __________________ '72 K-20 EFI'ed 250 Inline/4spd stake body, Farm Truck '71 C-20 Cummins Diesel Powered, In storage thanks to $5.00 diesel! '69 3500 GMC 305V-6/4spd, Still under reconstruction.......... Inlines Rule! 6 soldiers standing is better than 8 laying down!!!!!!!! Last edited by TP from Cntl PA; 08-09-2005 at 07:01 PM.

08-09-2005, 07:38 PM	#8
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	red x here...and tried going to the picture's URL and I was not permitted to look at it.

08-09-2005, 07:57 PM	#9
crew70 Registered User Join Date: Jan 2002 Location: shafer,mn,usa Posts: 316	I have had several HO52 and mine now has the bolt on the side. only dif I have seen is brake size. __________________ 70 chevy 3/4 ton 4x4 402ci crewcab 3/4ton 94 gmc 1 ton dually crewcab 454ci 99 suburban 5.7 2001 500cc ski-doo mxz 95 500cc ski doo fan 650 bombardiar 4 wheeler

08-09-2005, 07:59 PM	#10
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	That's true everything I've seen shows the biggest difference between the two(H052/H072) is the size of the brakes. __________________ 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



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.