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98 Front diff to 95

THIS FORUM IS FOR ANY QUESTIONS ON THE 7.25" IFS FRONT DIFF, CV HALF SHAFTS AND FRONT DRIVE SHAFT.

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thegreenmachine
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98 Front diff to 95

Post by thegreenmachine » Tue Jan 24, 2012 9:53 pm

so this is why i beleive the diff is pooched. there is also way to much movement in the driveshaft at that point. and the grinding and weird smell kinda gave me a hint too.

my question is, will a 98 RPO GT4 work in a 95 RPO GT4?
and if so, is it a bolt in? or swapping a bunch of parts.....

:canuk:
Attachments
diff.JPG
driveshaft to diff
2003 Chevrolet Astro 4wd np233c transfercase 245/75/16 ETS Trailermaster tires
ImageImageImage
Previous:
1995 Safari AWD (death by torsion bar. a.k.a. "the final straw")
1999 Safari AWD ( death by tree x2 )
1997 safari rwd cargo ( sold @ 450,000+ km )

LiftedAWDAstro
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Re: 98 Front diff to 95

Post by LiftedAWDAstro » Wed Jan 25, 2012 1:27 am

In a nutshell...No it will not work. Will it bolt in...yes. The problem lies in the different CV half shafts. The Housings are machined different and take different axle bearings. The carrier, pinion and internal bearings are the same though.If you can get the CV half shafts from the 98, I think they may bolt into the hub bearings. As far as I know this hasn't been done or proven to work. They list different part numbers for the hub bearings so that is why I am unsure on that part.
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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doyoulikeithere
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Re: 98 Front diff to 95

Post by doyoulikeithere » Wed Jan 25, 2012 1:55 am

thegreenmachine wrote:so this is why i beleive the diff is pooched. there is also way to much movement in the driveshaft at that point. and the grinding and weird smell kinda gave me a hint too. my question is, will a 98 RPO GT4 work in a 95 RPO GT4? and if so, is it a bolt in? or swapping a bunch of parts..... :canuk:
X2 on Lifted's reply.
The half shafts are of a different design, early(95) vs late(98) model and they must bolt to the correct model of Front Diff Housing. As Lifted said, the guts can interchange just fine, except for the flange that the half shaft bolts too.
Someone needs to find out IF the late half shafts can insert into the early model Hubs. I would suspect that if the 2 bearing part numbers are different, but the part number for the early & late hub is the same, you might get away with it, if you use new bearings and the 98 half shafts. Wanna be the first to look into doing this!! and report back to our mothership?
2021 Yamaha Tenere 700 - Blue.
2016 Yamaha XSR900 - Silver.
1990 Astro - AWD - Brown.
1987 Astro - With 5 Speed & 4wd - Silver & Blue.

User avatar
thegreenmachine
I get chills without my van.
Posts: 81
Joined: Sun Oct 03, 2010 4:50 pm
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How many wheels are on an Astro van? (4): 4
Location: chilliwack B.C.

Re: 98 Front diff to 95

Post by thegreenmachine » Wed Jan 25, 2012 2:15 am

thanks for the info.

but, unfortunatly i'm budgeted by the wife to fix as cheap as possible ( and correctly of course ) and she lacks the patience for me to alien probe the possiblity and report to the mother ship......

so next questions....
will the flanges interchange???
2003 Chevrolet Astro 4wd np233c transfercase 245/75/16 ETS Trailermaster tires
ImageImageImage
Previous:
1995 Safari AWD (death by torsion bar. a.k.a. "the final straw")
1999 Safari AWD ( death by tree x2 )
1997 safari rwd cargo ( sold @ 450,000+ km )

User avatar
doyoulikeithere
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How many wheels are on an Astro van? (4): 4
Location: Misty Mountains of Cowichan BC.

Re: 98 Front diff to 95

Post by doyoulikeithere » Wed Jan 25, 2012 2:56 am

thegreenmachine wrote:will the flanges interchange???
Doubt it.
LiftedAWDAstro wrote:The Housings are machined different and take different axle bearings.
here is a picture of the early style...
Attachments
S10 front diff.gif
2021 Yamaha Tenere 700 - Blue.
2016 Yamaha XSR900 - Silver.
1990 Astro - AWD - Brown.
1987 Astro - With 5 Speed & 4wd - Silver & Blue.

User avatar
thegreenmachine
I get chills without my van.
Posts: 81
Joined: Sun Oct 03, 2010 4:50 pm
antispam: No
How many wheels are on an Astro van? (4): 4
Location: chilliwack B.C.

Re: 98 Front diff to 95

Post by thegreenmachine » Wed Jan 25, 2012 6:32 pm

Thanks again, i knew it was too good to be true.

it is really hard to find a 95 3.7.3 front diff, does anyone know of any compatibles from other vehicles?
2003 Chevrolet Astro 4wd np233c transfercase 245/75/16 ETS Trailermaster tires
ImageImageImage
Previous:
1995 Safari AWD (death by torsion bar. a.k.a. "the final straw")
1999 Safari AWD ( death by tree x2 )
1997 safari rwd cargo ( sold @ 450,000+ km )

User avatar
doyoulikeithere
ASV Supporter
ASV Supporter
Posts: 2091
Joined: Wed Nov 18, 2009 4:27 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Misty Mountains of Cowichan BC.

Re: 98 Front diff to 95

Post by doyoulikeithere » Wed Jan 25, 2012 8:45 pm

I have one sitting here. 3.73, from a 95 awd.
You can use S10 Front axle as well, but gotta lock it into 4wd (easy peasy), cuz the S10 is part time 4wd.
2021 Yamaha Tenere 700 - Blue.
2016 Yamaha XSR900 - Silver.
1990 Astro - AWD - Brown.
1987 Astro - With 5 Speed & 4wd - Silver & Blue.

LiftedAWDAstro
Site Admin
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Posts: 4430
Joined: Sat Sep 09, 2006 10:35 pm
How many wheels are on an Astro van? (4): 6
Location: New Haven, NY

Re: 98 Front diff to 95

Post by LiftedAWDAstro » Thu Jan 26, 2012 2:06 am

What you have is a busted pinion bearing from the looks of the pic. To fix this using your 98 diff, pull the pinion and carrier out of the 98. Pull the same out of the 95 and swap the 98 parts into the 95 housing. You will need a new pinion seal, crush sleeve and possibly bearings. The bearings depend on the condition of the 98's bearings. You will need to do a complete setup to verify the preload and backlash is correct.
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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