anyone know a lot about the rear axles?

IF YOU HAVE QUESTIONS ON THE REAR DRIVE SHAFT OR AXLE, IT GOES HERE.
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markmitchinnh
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anyone know a lot about the rear axles?

Post by markmitchinnh »

I bought a G80 posi unit with no gears , the axle it came from was a 3:42 as is my stock open rear axle. Can I use my stock gears or are the gears that go with the posi different?
Recently bought a 1989 Astro RS from Florida. Replaced stock engine witha 1997 5.7 vortec with TBI and replaced transmission with rebuilt 700R4 with mild shift kit.
Bought on Monday the 16th of April 2012

LiftedAWDAstro
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Re: anyone know a lot about the rear axles?

Post by LiftedAWDAstro »

You can use the posi but you may need a carrier shim kit as you will need to adjust the carrier preload and backlash properly or you'll destroy the gears.
Current rides:
2013 Toyota Tundra DC 4x4
2008 Dodge Nitro 4x4
2005 Nissan Sentra 1.8S Special Edition

Mileage spreadsheet

Vans owned:
1986 Safari 2.5L 4 speed manual - scrapped
1995 Astro 2WD conversion 4.11 posi, shift kit, DHC rock rails - sold to Skippy
1998 Astro 4x4 D44, D60, NP231, full hydraulic system with 9k# Milemarker winch and snow plow - sold to Lockdoc
2003 Astro AWD all stock - traded for a 3/4 ton truck
2005 AWD, 4.10's - sold to skippy
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1Gary
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Re: anyone know a lot about the rear axles?

Post by 1Gary »

Mark-here is a thought.Your in there anyways,so why not swap in some performance gear ratios like 3.73's??.Money wise you not going to spend that much more.
1979 Malibu drag race only car
1999 Sonoma 4.3 5 speed-Rufus
1989 Astro-Ole Yellar cancelled-still selling off parts
1985 Astro-shop van R.I.P. my friend
1994 Astro LT RWD W4.3 rod knock RIP
1982 Winnebago single rear wheel-Chevy 350 Scraped 1/28/13-broken dreams......


Rochester,NY

Topic author
markmitchinnh
I sleep in my van
Posts: 589
Joined: Wed Oct 13, 2010 2:07 pm
Location: Barrington NH

Re: anyone know a lot about the rear axles?

Post by markmitchinnh »

1gary the 3:42 gear ratio works with my set up and future plans and I think 3:73 would ruin my mileage and as a DJ I need to get the best mileage I can to keep my profits as profits. At least until I sell the business this coming September. I have spinal problems from my airborne days in the military and every time I DJ my back and neck hurt the next day. So I decided that since I have my pension why do something that aggravates the problem.
Recently bought a 1989 Astro RS from Florida. Replaced stock engine witha 1997 5.7 vortec with TBI and replaced transmission with rebuilt 700R4 with mild shift kit.
Bought on Monday the 16th of April 2012
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LaGrasta
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Re: anyone know a lot about the rear axles?

Post by LaGrasta »

My new taller 16" tires are making my tranny work really hard, I have to change the rear end gearing before it dies altogether.
I'm seriously considering 3.73, any place to purchase you can recommend? I found some great used deals on ebay so far.
1998 Astro, 246,000 miles

K&N air filter
TruCool trans cooler
2" Overland lift & 15" BFG Terrain, 3.73 gears
JET Performance SCU-2000 (Speed Control Unit)
Gabriel Ultra shocks, rear AirLift bags & sway bar
Draw-Tite Dual Port Hitch System, hitch-mounted bike rack (4), hitch-mounted cargo tray, Thule roof-mounted cargo box

LiftedAWDAstro
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Re: anyone know a lot about the rear axles?

Post by LiftedAWDAstro »

Buying used you have to be very careful to make sure they are a matched set and are in great shape, wear wise. Make sure they are not "thick" gears for a 3.08 and lower series 2 carrier. Since you have 3.23's, there is no need to buy a new carrier unless you are also doing a posi install. I also don't buy used aftermarket gears. Only GM for used. Too many guys swap gears and then get rid of them for noise due to poor installations. They may not be broke in correct and you may always have noise too.

When buying a master install kit, be sure they include Koyo or Timken bearings as these are what are used in the axles from new. Are you doing the install yourself?
Current rides:
2013 Toyota Tundra DC 4x4
2008 Dodge Nitro 4x4
2005 Nissan Sentra 1.8S Special Edition

Mileage spreadsheet

Vans owned:
1986 Safari 2.5L 4 speed manual - scrapped
1995 Astro 2WD conversion 4.11 posi, shift kit, DHC rock rails - sold to Skippy
1998 Astro 4x4 D44, D60, NP231, full hydraulic system with 9k# Milemarker winch and snow plow - sold to Lockdoc
2003 Astro AWD all stock - traded for a 3/4 ton truck
2005 AWD, 4.10's - sold to skippy
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LaGrasta
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Posts: 724
Joined: Fri Jan 19, 2007 2:07 pm
Location: Mission Viejo, CA
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Re: anyone know a lot about the rear axles?

Post by LaGrasta »

I am doing the install myself and a friend, although when I swapped from 3.42 to 3.24 I paid to have it done. Whew, it was expensive! At that time, i bought new gears because I didn't trust getting a used set that would be up to snuff. I guess I should do the same now and buy new.
I bought form here last time, http://www.gearsareus.com/
1998 Astro, 246,000 miles

K&N air filter
TruCool trans cooler
2" Overland lift & 15" BFG Terrain, 3.73 gears
JET Performance SCU-2000 (Speed Control Unit)
Gabriel Ultra shocks, rear AirLift bags & sway bar
Draw-Tite Dual Port Hitch System, hitch-mounted bike rack (4), hitch-mounted cargo tray, Thule roof-mounted cargo box
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