Rearend Parts and Posi...where & what to buy - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**1971Stepside** · 10-08-2002, 02:46 PM

My next big step is to buy a 3.73 posi and all new bearings seals etc for my 12 bolt.

Problem is when I go to web sites and look at these things it seems the posi will be anywhere from 350 to 450 bucks. What is the difference in them?

Second, can't I buy a kit that gives me all the bearings, seals, gaskets, etc that I need?

I got a price of $60 to have it set up by a guy that does this for a living.....I thought that was cheap, but he said he didn't get a break on parts and I would be better off to buy the parts and bring them to him.

What should I have to pay to get a posi and all new seals? I will re-use my old ring and pinion.

**COBALT** · 10-08-2002, 05:47 PM

I don't know if you've called these guys but they're kick-a$$ for info.

Randy's Ring & Pinion

**1971Stepside** · 10-08-2002, 05:58 PM

Thanks Cobalt. I called them and you are correct, they are great. Great prices too.

Entire rebuild kit to include all gaskets, bearings, crush ring, etc for 112.00
Eaton 3.73 Posi: 339.00
Chrome Diff Cover: 19.00

Now all I need is the wife's checkbook!!

Mike C · 10-08-2002, 06:17 PM

Cobalt has definitely steered you in the right direction with Randys. I would forgo the chrome cover and get stainless ARP bolts and re-paint your OEM cover. They are MUCH less leak prone and the chrome jobs rust after a year or two. (I have one on the JImmy, but only because of catastrophic failure...) $60 is a smokin' deal on an R&P setup. I've rebilt probably 30 diffs now and it's at least 4 hours to do it right.

JimKshortstep4x4 · 10-09-2002, 07:10 AM

Stepside,

Have you looked at Tom's differentials?

Eaton posi $280

Installation kit $100

www.tomsdifferentials.com/tomp.htm

Jim

mikep · 10-09-2002, 07:30 AM

$60 is a great deal on ring and pinion set up but thats not what you are getting. Sounds to me from your post that you are just installing a carrier and resealing your rear end. I know used carriers go for about $150 around here even if you pay too much and new clutches, bearings and seals will set you back about $120. Installing the carrier in your rear end isnt diffficult. You are not setting pinion depth in that case which is the most "difficult" part of setting upoa a rear end . You are only adjusting the gear mesh IF you even have to do that. White grease and a shim pack is all you need and you probably wont even use the shims. I know $60 isnt much and if that gives you peace of mind then great but personally I'd rather do it myself even If I had never done something like it before . That way you save a few bucks and learn a new skill. You have plenty of instructors who will teach you how for FREE right here.

70c10 · 10-09-2002, 08:03 AM

Mikep,
I am looking into doing the exact same thing as 71 is doing. My shop told me it would cost $150 plus I would need new carrier bearings. Tom's Diffs quoted me at $280 for the posi plus $32 for the bearings and races and another $25 for shims. They said it was fairly easy. I have never done this. It sounds like you know how to do this. How do I go about this project as far as removing my old one first? Do I have to pull my axles?. Do I need any special tolls?. Thanks

Jeff M. · 10-09-2002, 08:33 AM

I put the Eaton posi carrier in my truck. No special tools were needed. When I put the bearings on the carrier, I put the carrier in the freezer and the bearings in the oven and they tapped on without any problems. The stock shims worked perfectly, the gears set up without any problems. The rear end works great. Easy swap and the 'fun factor' has greatly increased!

70c10 · 10-09-2002, 08:53 AM

Does anybody know of a website with photos showing how this is done?. Jeff M how much of a noticeable difference did the posi make on your truck?

**1971Stepside** · 10-09-2002, 09:19 AM

The new issue of Truck Builder has a tech article on how to put a posi in a 12 bolt. I read it and am still confused. For $60 I will have the piece of mind that it is in there right. Thanks for the heads up on Toms. Sounds like the same stuff for less money. I will give them a call.

I hadn't heard the chrome covers leaked. I am not worried about rust as my truck should never see a day of rain unless the garage door is open!

mikep · 10-09-2002, 09:43 PM

Ive never had a chrome cover leak . Use a 1/8 bead of red RTV and let it set up completely on each side of the gasket before installing it. I do that to all gasket s and I dont have leaks on anything.

To install the new differential all you have to do is

A few notes first. You are not changing pinion depth so the majority of the set up blues are not there. Adjusting gear mesh is all that necesarry here. Setting pinion depth when changing ring and pinion is not difficult either but I wont cover that right not to avoid confusion. You need some specialized tools to do that . To change carriers you do not need any specialized tools other than common hand tools. Idid this same procedure over the weekend and it took me about three hours total until I was driving it. The first time I did it was when i was 15 with no outside instruction other than a poorly written manual so its not that difficult for the beginner.

1. On Full floating or semi floating axles pull the axles out a foot or so. On C clip axles you need to pull the cover first and remove the differential cross shaft .

2. Take off the cover

3. remove the carrier bolts

4. pull the carrier. sometimes theyre a little tight especially on dana 60's . You make need to turn the driveshaft to get the carrier to walk its way out.

5. remove the ring gear from the old carrier. might need to heat the ring gear with a propane torch to expand it a bit so it slides off the carrier. Dont hit it with anything harder than a lead hammer. Install the ring gear on the new carrier. toque bolts to spec. Typically 110 lbs or so.

6. Install the new carrier in the differential housing . Sometimes its pretty tight especially if you are using new carrier bearings.

7. torque the carrier bearing caps in place . check your chiltons for torque specs. 90-100 depending on the rear end.

8. turn the carrier over with the driveshaft yoke. If everything turns OK and it should if you are using the right carrier.

9. smear some white lithium grease on the teeth of the ring gear

10. install the axles with a few bolts if full floating. If c clip type then just slide them in for now

11 . pull you E brake a bit to give some drag on the brakes

12. turn the driveshaft over by hand or with a breaker bar

13. check the pattern the pinion leaves in the grease. If its right in the middle of the gear tooth you are good to go. 90% + of the time it will be as you have not changed the pinion depth and most modern rear ends are pretty standardized for dimensions. If the pattern is low on the tooth you'll need to insert a carrier shim on the left side as you look at it from the rear between the bearing race and the housing . .005 is a good place to start. Most good auto parts stores will sell you a rear end set up pack that includes carrier bearing shims. Randy's ring and pinion too as well as several sellers o ebay .

Once you get it in the middle of the gear face then wrap it up . Your done. Use friction modifier lube with your gear oil if its a clutch type posi.

Jeff M. · 10-09-2002, 10:45 PM

70c10, in normal driving not much difference. But lay into it and I get the torque fishtail while the tires are spinning. Also, watch out on corners and water cause it will get away from ya quick. At the track I was able to knock off 3/4 of a second. This is with a 3.08 ratio. I'm thinkin of buying a set of gears and mount the slicks from the Chevelle and give it a try next season. Fun fun fun.........

10-08-2002, 02:46 PM	#1
1971Stepside Almost Satisfied Join Date: Mar 2002 Location: Springfield, MO Posts: 2,928	Rearend Parts and Posi...where & what to buy My next big step is to buy a 3.73 posi and all new bearings seals etc for my 12 bolt. Problem is when I go to web sites and look at these things it seems the posi will be anywhere from 350 to 450 bucks. What is the difference in them? Second, can't I buy a kit that gives me all the bearings, seals, gaskets, etc that I need? I got a price of $60 to have it set up by a guy that does this for a living.....I thought that was cheap, but he said he didn't get a break on parts and I would be better off to buy the parts and bring them to him. What should I have to pay to get a posi and all new seals? I will re-use my old ring and pinion. __________________ 1971 C10 Stepside. LSx 6.0 with BTR Stage IV, Speed Engineering Headers, 4L80e transmission w/3200 Circle-D Stall. 3.73. Posi. Purchased this truck when I was 17. I started the rebuild (or take apart) in 1993. I have drug it around all over the country in pieces. Finally back on the road in 2021. "I can't complain, but sometimes I still do. Life's been good to me so far."

10-08-2002, 05:47 PM	#2
COBALT Senior Member Join Date: Sep 2001 Location: Seattle, WA, USA Posts: 5,817	I don't know if you've called these guys but they're kick-a$$ for info. Randy's Ring & Pinion __________________ '69 3/4 ton C20 2wd-350ci/TH400 '69 3/4 ton Custom 20 2wd-350ci/4sp Manual '99 2wd 5.7 Chevy Tahoe Seattle, WA.

10-08-2002, 05:58 PM	#3
1971Stepside Almost Satisfied Join Date: Mar 2002 Location: Springfield, MO Posts: 2,928	Thanks Cobalt. I called them and you are correct, they are great. Great prices too. Entire rebuild kit to include all gaskets, bearings, crush ring, etc for 112.00 Eaton 3.73 Posi: 339.00 Chrome Diff Cover: 19.00 Now all I need is the wife's checkbook!! __________________ 1971 C10 Stepside. LSx 6.0 with BTR Stage IV, Speed Engineering Headers, 4L80e transmission w/3200 Circle-D Stall. 3.73. Posi. Purchased this truck when I was 17. I started the rebuild (or take apart) in 1993. I have drug it around all over the country in pieces. Finally back on the road in 2021. "I can't complain, but sometimes I still do. Life's been good to me so far."

10-08-2002, 06:17 PM	#4
Mike C Registered User Join Date: Dec 1999 Location: Austin, TX, USA Posts: 7,714	Cobalt has definitely steered you in the right direction with Randys. I would forgo the chrome cover and get stainless ARP bolts and re-paint your OEM cover. They are MUCH less leak prone and the chrome jobs rust after a year or two. (I have one on the JImmy, but only because of catastrophic failure...) $60 is a smokin' deal on an R&P setup. I've rebilt probably 30 diffs now and it's at least 4 hours to do it right. __________________ 44 Willys MB 52 M38A1 64 Corvette Coupe 68 Camaro 'vert LT1 & TH700 69 Z/28 355 12.6's @110 69 Chevy Short Step 4 1/2"/7" drop 72 Jimmy 4WD 4spd 4" & 35's 02 GMC 2500HD 4x4 Duramax

10-09-2002, 07:30 AM	#6
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	$60 is a great deal on ring and pinion set up but thats not what you are getting. Sounds to me from your post that you are just installing a carrier and resealing your rear end. I know used carriers go for about $150 around here even if you pay too much and new clutches, bearings and seals will set you back about $120. Installing the carrier in your rear end isnt diffficult. You are not setting pinion depth in that case which is the most "difficult" part of setting upoa a rear end . You are only adjusting the gear mesh IF you even have to do that. White grease and a shim pack is all you need and you probably wont even use the shims. I know $60 isnt much and if that gives you peace of mind then great but personally I'd rather do it myself even If I had never done something like it before . That way you save a few bucks and learn a new skill. You have plenty of instructors who will teach you how for FREE right here. __________________ No truck :-(

10-09-2002, 07:10 AM	#5
JimKshortstep4x4 Senior Member Join Date: Jul 2001 Location: Muskegon,MI,USA Posts: 6,026	Stepside, Have you looked at Tom's differentials? Eaton posi $280 Installation kit $100 www.tomsdifferentials.com/tomp.htm Jim

10-09-2002, 08:03 AM	#7
70c10 67-72 Addict! Join Date: Feb 2002 Location: The TAX State! Posts: 7,857	Mikep, I am looking into doing the exact same thing as 71 is doing. My shop told me it would cost $150 plus I would need new carrier bearings. Tom's Diffs quoted me at $280 for the posi plus $32 for the bearings and races and another $25 for shims. They said it was fairly easy. I have never done this. It sounds like you know how to do this. How do I go about this project as far as removing my old one first? Do I have to pull my axles?. Do I need any special tolls?. Thanks __________________ Jim 1970 C/10 Fleetside w/Ghost Flames Lowered 4.5" front and 4" rear (Raked) 355/350 Turbo w/shift kit 10" Redneck Performance Verter w/2500 stall Hooker Super Comps part#2808-1 Performer RPM Air-Gap 12 Bolt w/3:73 gears- Eaton Posi Comp Cams XE262 with 1.6 Crane Energizers, Road Demon 625 and Brodix IK 180 heads

10-09-2002, 08:33 AM	#8
Jeff M. Registered User Join Date: Feb 2000 Location: Pixley, Ca. Posts: 484	I put the Eaton posi carrier in my truck. No special tools were needed. When I put the bearings on the carrier, I put the carrier in the freezer and the bearings in the oven and they tapped on without any problems. The stock shims worked perfectly, the gears set up without any problems. The rear end works great. Easy swap and the 'fun factor' has greatly increased! __________________ 69 C-10 CST Short Fleet, Factory Air, BB427-400 Auto-2400 stall-tilt-cruise-Tach & Vac Gagues, 4/6 drop, power one piece side windows, Eaton posi.

10-09-2002, 08:53 AM	#9
70c10 67-72 Addict! Join Date: Feb 2002 Location: The TAX State! Posts: 7,857	Does anybody know of a website with photos showing how this is done?. Jeff M how much of a noticeable difference did the posi make on your truck? __________________ Jim 1970 C/10 Fleetside w/Ghost Flames Lowered 4.5" front and 4" rear (Raked) 355/350 Turbo w/shift kit 10" Redneck Performance Verter w/2500 stall Hooker Super Comps part#2808-1 Performer RPM Air-Gap 12 Bolt w/3:73 gears- Eaton Posi Comp Cams XE262 with 1.6 Crane Energizers, Road Demon 625 and Brodix IK 180 heads

10-09-2002, 09:19 AM	#10
1971Stepside Almost Satisfied Join Date: Mar 2002 Location: Springfield, MO Posts: 2,928	The new issue of Truck Builder has a tech article on how to put a posi in a 12 bolt. I read it and am still confused. For $60 I will have the piece of mind that it is in there right. Thanks for the heads up on Toms. Sounds like the same stuff for less money. I will give them a call. I hadn't heard the chrome covers leaked. I am not worried about rust as my truck should never see a day of rain unless the garage door is open! __________________ 1971 C10 Stepside. LSx 6.0 with BTR Stage IV, Speed Engineering Headers, 4L80e transmission w/3200 Circle-D Stall. 3.73. Posi. Purchased this truck when I was 17. I started the rebuild (or take apart) in 1993. I have drug it around all over the country in pieces. Finally back on the road in 2021. "I can't complain, but sometimes I still do. Life's been good to me so far." Last edited by 1971Stepside; 10-09-2002 at 09:33 AM.

10-09-2002, 09:43 PM	#11
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	Ive never had a chrome cover leak . Use a 1/8 bead of red RTV and let it set up completely on each side of the gasket before installing it. I do that to all gasket s and I dont have leaks on anything. To install the new differential all you have to do is A few notes first. You are not changing pinion depth so the majority of the set up blues are not there. Adjusting gear mesh is all that necesarry here. Setting pinion depth when changing ring and pinion is not difficult either but I wont cover that right not to avoid confusion. You need some specialized tools to do that . To change carriers you do not need any specialized tools other than common hand tools. Idid this same procedure over the weekend and it took me about three hours total until I was driving it. The first time I did it was when i was 15 with no outside instruction other than a poorly written manual so its not that difficult for the beginner. 1. On Full floating or semi floating axles pull the axles out a foot or so. On C clip axles you need to pull the cover first and remove the differential cross shaft . 2. Take off the cover 3. remove the carrier bolts 4. pull the carrier. sometimes theyre a little tight especially on dana 60's . You make need to turn the driveshaft to get the carrier to walk its way out. 5. remove the ring gear from the old carrier. might need to heat the ring gear with a propane torch to expand it a bit so it slides off the carrier. Dont hit it with anything harder than a lead hammer. Install the ring gear on the new carrier. toque bolts to spec. Typically 110 lbs or so. 6. Install the new carrier in the differential housing . Sometimes its pretty tight especially if you are using new carrier bearings. 7. torque the carrier bearing caps in place . check your chiltons for torque specs. 90-100 depending on the rear end. 8. turn the carrier over with the driveshaft yoke. If everything turns OK and it should if you are using the right carrier. 9. smear some white lithium grease on the teeth of the ring gear 10. install the axles with a few bolts if full floating. If c clip type then just slide them in for now 11 . pull you E brake a bit to give some drag on the brakes 12. turn the driveshaft over by hand or with a breaker bar 13. check the pattern the pinion leaves in the grease. If its right in the middle of the gear tooth you are good to go. 90% + of the time it will be as you have not changed the pinion depth and most modern rear ends are pretty standardized for dimensions. If the pattern is low on the tooth you'll need to insert a carrier shim on the left side as you look at it from the rear between the bearing race and the housing . .005 is a good place to start. Most good auto parts stores will sell you a rear end set up pack that includes carrier bearing shims. Randy's ring and pinion too as well as several sellers o ebay . Once you get it in the middle of the gear face then wrap it up . Your done. Use friction modifier lube with your gear oil if its a clutch type posi. __________________ No truck :-(

10-09-2002, 10:45 PM	#12
Jeff M. Registered User Join Date: Feb 2000 Location: Pixley, Ca. Posts: 484	70c10, in normal driving not much difference. But lay into it and I get the torque fishtail while the tires are spinning. Also, watch out on corners and water cause it will get away from ya quick. At the track I was able to knock off 3/4 of a second. This is with a 3.08 ratio. I'm thinkin of buying a set of gears and mount the slicks from the Chevelle and give it a try next season. Fun fun fun......... __________________ 69 C-10 CST Short Fleet, Factory Air, BB427-400 Auto-2400 stall-tilt-cruise-Tach & Vac Gagues, 4/6 drop, power one piece side windows, Eaton posi.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.