G80 & GT4 for 2004 AWD Astro Conversion

IF YOU HAVE QUESTIONS ON THE REAR DRIVE SHAFT OR AXLE, IT GOES HERE.

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timelessbeing
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How many wheels are on an Astro van? (4): 4

Re: G80 & GT4 for 2004 AWD Astro Conversion

Post by timelessbeing » Sat Jun 01, 2019 8:45 pm

Oh shoot, you're right. Haha I forgot we were talking about Astros which have 7.6" units in the rear. I keep thinking of my current Savana which has a 8.6" rear. But the front is 7.6" I think.

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How many wheels are on an Astro van? (4): 4
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Re: G80 & GT4 for 2004 AWD Astro Conversion

Post by Bret Schmerker » Sun Oct 20, 2019 2:45 am

:bounce: As a side note for those considering ancient GM axles with 3.73:1 R&P (RPO GT4), I already looked at the 1955-series GM 8.400" dropout used on Chevrolet and Pontiac passenger cars through 1963 and would not recommend it for those needing a locker; EATON® supports the 8.400" only with a Positraction®. Nothing at all for the 1955 GM 9.375" dropout used on the 3100 and C-10. The Currie® 9" dropout is strong enough to take the torque multiplication of a transfer case of up to 4:1 reduction with the stock V6-4.3 and AWD/4WD Hydra-Matic® 4L60-E, and EATON supports the 9" with Detroit Locker and Detroit Truetrac.
1997 GMC M11006 (Safari SLE, 2WD, V6-4300/4L60-E/7.625" 3.73:1 open)
Acquired Jul 2018 / In service Sep 2018 - present

forrestmccarthy
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How many wheels are on an Astro van? (4): 4

Re: G80 & GT4 for 2004 AWD Astro Conversion

Post by forrestmccarthy » Sat Oct 26, 2019 8:19 am

I just picked up my Astro Quattro from the shop. I ended up going with Yukon 3.73 Ring and Pinions that don't appear to make any additional noise. This is with the the Truetrac in the rear and the MFactory in the front. The front torsion is mounted in the stock aluminum casing.

I haven't had a chance to give it the full snow test yet but it seems to handle corners well when in 4WD. I took it into some mud and gravel to see if I could spin both rear wheels. Impossible to get anything to spin in 4WD...a good problem to have! In 2WD I was able to get both back wheels to spin in a deep mud puddle. Fun stuff.

In the last few months I've also installed a Blazer transfer case and HD leaf springs along with 1.5" hubcentric wheel spacers. I did have to modify the sliding door yet appreciate the wider stance. Maybe it's just psychological, but I now have more confidence side hilling. This is all on 30.5" diameter tires.

Excited to see how the Astro Quattro (Quastro?) handles in the snow.

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Re: G80 & GT4 for 2004 AWD Astro Conversion

Post by Captn. Crunch » Mon Oct 28, 2019 12:04 am

Quote: I just picked up my Astro Quattro from the shop. I ended up going with Yukon 3.73 Ring and Pinions that don't appear to make any additional noise. This is with the the Truetrac in the rear and the MFactory in the front. The front torsion is mounted in the stock aluminum casing

Just a minor error I’d like to point out in the above statement- “ the front torsion is mounted in the stock aluminum casing”
Should read the front Torsen...
Torsion is a front suspension piece - I knew what you meant
Just so no one else is confused :cheers:
Captn. Crunch
"I don't beat my rig-I use it to it's maximum potential"
1994 Safari conversion (sold) and miss'n it!
1999 Safari SLE AWD junked
2003 GMC Safari AWD SLT
cast iron Torsen equipped front diff
S-10 leafs-G80 rear w/3.73’s
2” body lift w/Falken Wildpeak AT’s

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