Little Help on Gearing - The 1947 - Present Chevrolet & GMC Truck Message Board Network

1STtimePRo'71 · 10-12-2005, 10:50 PM

What's the stock ring and pinion size on a 71 Chevy 3/4 ton 4x4 with a 350? Here is a pic of the two diffs. I'm looking to re-gear. I'm not even sure what the gearing in it now is

But It's too much for the highway. Anybody help me out?

1969 GMC · 10-12-2005, 10:52 PM

The actual size of the gear, or the ratio?
Stock should be 4.11 rear, and something similar in the front.
The ring gear of your rear axle is around 10-1/8", and the front is 8-3/4".

1STtimePRo'71 · 10-12-2005, 11:06 PM

I'm just trying to gain some info because I want to purchase a new set of gears within the next month or so. I was assuming that the gearing was 4.11 but I didnt know the size of the ring gear. I'm going to 3.73's.

1969 GMC · 10-13-2005, 12:39 AM

The highest gears you can get for your rearend are 3.90's, and they are an aftermarket set that is no longer made (hard to find). You will have to get another rearend to go to 3.73's.

1STtimePRo'71 · 10-13-2005, 12:43 AM

Really, Because it's an Eaton HO52? Crap, I bet I cant even find a nice diff cover for that either huh? Randy's ring and Pinion said they stocked gearsets for early 70's 3/4ton 4x4's. Who would have thought early 70's started in 73

Is my front a dana44?

al's71gmc · 10-13-2005, 06:34 AM

Yes, your front is a D44.

**special-K** · 10-13-2005, 10:25 AM

Some trucks had Dana 60 rears before`73.You can probably buy a complete Dana 60 or 14-bolt with the gears you want for what a new ring & pinion,install kit,and labor would be,if not less.Same for the front,but you can get alot of gear ratios for the D44.

1969 GMC · 10-13-2005, 11:40 AM

And, no chrome/fancy diff covers for the Eaton, either. I saw one guy on the Napco website sandblast his and take them to a chromer. Looked pretty nice, but $$$. Let me see if I can find a pic.

budbeater · 10-13-2005, 01:36 PM

Welcome to the nightmare of the Eaton HO52. If you don't have any money into your eaton run, don't walk, to a GM 14bolt. From what I understand the HO52 only came with 3 gear choices 4.10, 4.56, and 5.13. The 4.10s are not bad with 33+ tires. I have 35s on my 71 and it is a great freeway flyer. You are going to find that you can't get brake parts, axles, centers, gears, etc for the HO52. All that being said the HO52 is severely strong and properly maintained should be solid forever.

Budbeater

1STtimePRo'71 · 10-13-2005, 07:27 PM

I also have 33's on mine. But still at highway speed I can do 60 at best without wondering how many more rpm's to squeeze out of her. I mean she's screamin at 60!! Are the pumpkins in the same position on all of the D44's?

**special-K** · 10-13-2005, 10:00 PM

Yes,on the D44 pumpkin location.Well,except Ferds with it on the opposite side.

budbeater · 10-13-2005, 11:11 PM

I'll bet you have 5.13s. I have the 4.10 (or 4.11) and I can bury the speedo. I am aerodynamic limited not rpm. Pull the cover and count the gears. Then find a 14bolt.

BBB

1967k30 · 10-14-2005, 09:58 AM

I have seen 3.73's listed for Eaton h052's somewhere.I forgot where though.They were like $280 for the R&P. with 4.10's you shouldn't have a problem running 80+ mph.

1STtimePRo'71 · 10-14-2005, 06:07 PM

I'd like to know where you saw that 3.73 r&p for a HO52. Because I cant find anything anywhere!!!

budbeater · 10-16-2005, 04:15 PM

From what other members that know alot more than me have said the HO52 only came with 4.10, 4.56, and 5.13 gears. If you can find some aftermarket gears in a different ratio you will be lucky. I did see in a magazine last month that someone in the Top Truck Challenge had some 5.13 gears from Yukon Gear in their HO52. Start by contacting Yukon and see what they have. I hate to beat a dead horse but you still would be better off sourcing out a 14 bolt axle. I am going through a disk swap on my HO52 because you can't find critical parts for the 12" brakes found on the 71 axle. I am about $1000 into the swap (counting all the bearings, seals, fluids, shop supplys etc). I could have had a newly rebuilt 14 bolt from Boyce Equiptment here in town for about $1300. If you change your gears you will still have old seals, bearings, brakes, and axles to deal with.

BBB

10-12-2005, 10:50 PM	#1
1STtimePRo'71 Registered User Join Date: Feb 2005 Location: Lake Crystal, MN Posts: 656	Little Help on Gearing What's the stock ring and pinion size on a 71 Chevy 3/4 ton 4x4 with a 350? Here is a pic of the two diffs. I'm looking to re-gear. I'm not even sure what the gearing in it now is But It's too much for the highway. Anybody help me out? Attached Images __________________ -Cory 1967 2 Wheel Chevy

10-12-2005, 10:52 PM	#2
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	The actual size of the gear, or the ratio? Stock should be 4.11 rear, and something similar in the front. The ring gear of your rear axle is around 10-1/8", and the front is 8-3/4". __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650

10-12-2005, 11:06 PM	#3
1STtimePRo'71 Registered User Join Date: Feb 2005 Location: Lake Crystal, MN Posts: 656	I'm just trying to gain some info because I want to purchase a new set of gears within the next month or so. I was assuming that the gearing was 4.11 but I didnt know the size of the ring gear. I'm going to 3.73's. __________________ -Cory 1967 2 Wheel Chevy

10-13-2005, 12:39 AM	#4
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	The highest gears you can get for your rearend are 3.90's, and they are an aftermarket set that is no longer made (hard to find). You will have to get another rearend to go to 3.73's. __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650

10-13-2005, 12:43 AM	#5
1STtimePRo'71 Registered User Join Date: Feb 2005 Location: Lake Crystal, MN Posts: 656	Really, Because it's an Eaton HO52? Crap, I bet I cant even find a nice diff cover for that either huh? Randy's ring and Pinion said they stocked gearsets for early 70's 3/4ton 4x4's. Who would have thought early 70's started in 73 Is my front a dana44? __________________ -Cory 1967 2 Wheel Chevy

10-13-2005, 06:34 AM	#6
al's71gmc 4 eyed fever Join Date: Jul 2005 Location: Eureka, Nevada Posts: 500	Yes, your front is a D44. __________________ 1971 GMC 2500 4x4 1972 GMC Sierra Grande 1/2 t 4x4-#1 son's truck. Recently completed resto. 4 YO daughter," Daddy, I like your truck better than Mom's." (2000 F350-ranch truck) Smart kid!!

10-13-2005, 10:25 AM	#7
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,863	Some trucks had Dana 60 rears before`73.You can probably buy a complete Dana 60 or 14-bolt with the gears you want for what a new ring & pinion,install kit,and labor would be,if not less.Same for the front,but you can get alot of gear ratios for the D44. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

10-13-2005, 11:40 AM	#8
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	And, no chrome/fancy diff covers for the Eaton, either. I saw one guy on the Napco website sandblast his and take them to a chromer. Looked pretty nice, but $$$. Let me see if I can find a pic. Attached Images __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650 Last edited by 1969 GMC; 10-13-2005 at 11:41 AM.

10-13-2005, 01:36 PM	#9
budbeater Registered User Join Date: Sep 2005 Location: Utah Posts: 63	Welcome to the nightmare of the Eaton HO52. If you don't have any money into your eaton run, don't walk, to a GM 14bolt. From what I understand the HO52 only came with 3 gear choices 4.10, 4.56, and 5.13. The 4.10s are not bad with 33+ tires. I have 35s on my 71 and it is a great freeway flyer. You are going to find that you can't get brake parts, axles, centers, gears, etc for the HO52. All that being said the HO52 is severely strong and properly maintained should be solid forever. Budbeater

10-13-2005, 07:27 PM	#10
1STtimePRo'71 Registered User Join Date: Feb 2005 Location: Lake Crystal, MN Posts: 656	I also have 33's on mine. But still at highway speed I can do 60 at best without wondering how many more rpm's to squeeze out of her. I mean she's screamin at 60!! Are the pumpkins in the same position on all of the D44's? __________________ -Cory 1967 2 Wheel Chevy

10-13-2005, 10:00 PM	#11
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,863	Yes,on the D44 pumpkin location.Well,except Ferds with it on the opposite side. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

10-13-2005, 11:11 PM	#12
budbeater Registered User Join Date: Sep 2005 Location: Utah Posts: 63	I'll bet you have 5.13s. I have the 4.10 (or 4.11) and I can bury the speedo. I am aerodynamic limited not rpm. Pull the cover and count the gears. Then find a 14bolt. BBB

10-14-2005, 09:58 AM	#13
1967k30 Senior Member Join Date: Sep 2005 Location: NE Posts: 363	I have seen 3.73's listed for Eaton h052's somewhere.I forgot where though.They were like $280 for the R&P. with 4.10's you shouldn't have a problem running 80+ mph. __________________ 01 2500 Duramax,6spd,4x4,Not stock. Estimated 550rwhp/1100rwfp on fuel only. 03 3500 Duramax,6spd,4x4,Pac-Brake,not stock Estimated 500rwhp/1000rwfp fuel only 67 K10 in many pieces Little Brothers truck 67 K20 Cummins 12V/NV4500/205, D60/Eaton w/ Detroit,37" Xterrains,crossover steering, Future plans,Twins and lots of fuel.

10-14-2005, 06:07 PM	#14
1STtimePRo'71 Registered User Join Date: Feb 2005 Location: Lake Crystal, MN Posts: 656	I'd like to know where you saw that 3.73 r&p for a HO52. Because I cant find anything anywhere!!! __________________ -Cory 1967 2 Wheel Chevy

10-16-2005, 04:15 PM	#15
budbeater Registered User Join Date: Sep 2005 Location: Utah Posts: 63	Re: Little Help on Gearing From what other members that know alot more than me have said the HO52 only came with 4.10, 4.56, and 5.13 gears. If you can find some aftermarket gears in a different ratio you will be lucky. I did see in a magazine last month that someone in the Top Truck Challenge had some 5.13 gears from Yukon Gear in their HO52. Start by contacting Yukon and see what they have. I hate to beat a dead horse but you still would be better off sourcing out a 14 bolt axle. I am going through a disk swap on my HO52 because you can't find critical parts for the 12" brakes found on the 71 axle. I am about $1000 into the swap (counting all the bearings, seals, fluids, shop supplys etc). I could have had a newly rebuilt 14 bolt from Boyce Equiptment here in town for about $1300. If you change your gears you will still have old seals, bearings, brakes, and axles to deal with. BBB



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