How to find S10 8.5" rear end
03-24-2013, 09:43 AM
#21
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Rear
So are the 8.5s more common in 4x4s? I'm planning on using c5 wheels on my project so the extra 2 in with on each side would mean using only a 1 in spacer. And the zr2 is 3 in wider on each side?
Last edited by Frogwood; 03-24-2013 at 05:47 PM. Reason: Wrong model
12-05-2013, 12:44 PM
#23
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After countless hours of googling and searching on other forums and comming up with no REAL answers to what s10 trucks had which rear end... i tookit into my own hands to find out exactly which trucks had the 8.5 rear end. I work at a dealership so finding out was fairly easy.... writing it all down wasnt haha. if you feel like i missed something or need to clarify feel free to ask or point it out. also i can get just about any GM part number you think of if you need one.
RPO codes:
GT4-3.73 gear ratio
GT5-4.10 gear ratio
GU4-3.08 gear ratio
GU6-3.42 gear ratio
G80- Positraction, Limited Slip
LB4- 4.3 V6 TBI
LN2- 2.2l 4cyl MFI
LU3- 4.3 V6
L35- 4.3 V6 CPI
M30- Auto 4 SPD trans
M50- Man 5 SPD trans
S10 Pickups
1995 s10 2wd 8.5 rear, (LB4,L35,M30,GU6)
1995-1997 s10 2wd 8.5 rear, (LN2,M30,GT5)
1996-1999 s10 2wd 8.5 rear, (L35,M50,GU4,G80)
2000-2002 s10 2wd 8.5 rear, (M50,GU4,G80)
2003 s10 2wd 8.5 rear, (LU3,M50,GU4,G80)
S10 Blazers
1995-1997 s10 blazer 2wd 8.5 rear, (L35,M50,GU6,G80)
1998-1999 s10 blazer 2wd 8.5 rear, (L35,M50,GU6,G80)
2000-2001 s10 blazer 2wd 8.5 rear, (L35,M50,GU6,G80)
2001-2004 s10 blazer 2wd 8.5 rear, (M50,GU6,G80)
2003-2005 s10 blazer 2wd 8.5 rear, (M50,GU6)
So... for example if you are looking for a 8.5 rear end with 3.42 gears and posi, you can find it in a v6 blazer 2wd with a manual 5spd trans...
There are also 8.5 rear ends in 4x4 s10's but i did not list them... i can if the majority wants them. Hope this helps find the rear end you want.
RPO codes:
GT4-3.73 gear ratio
GT5-4.10 gear ratio
GU4-3.08 gear ratio
GU6-3.42 gear ratio
G80- Positraction, Limited Slip
LB4- 4.3 V6 TBI
LN2- 2.2l 4cyl MFI
LU3- 4.3 V6
L35- 4.3 V6 CPI
M30- Auto 4 SPD trans
M50- Man 5 SPD trans
S10 Pickups
1995 s10 2wd 8.5 rear, (LB4,L35,M30,GU6)
1995-1997 s10 2wd 8.5 rear, (LN2,M30,GT5)
1996-1999 s10 2wd 8.5 rear, (L35,M50,GU4,G80)
2000-2002 s10 2wd 8.5 rear, (M50,GU4,G80)
2003 s10 2wd 8.5 rear, (LU3,M50,GU4,G80)
S10 Blazers
1995-1997 s10 blazer 2wd 8.5 rear, (L35,M50,GU6,G80)
1998-1999 s10 blazer 2wd 8.5 rear, (L35,M50,GU6,G80)
2000-2001 s10 blazer 2wd 8.5 rear, (L35,M50,GU6,G80)
2001-2004 s10 blazer 2wd 8.5 rear, (M50,GU6,G80)
2003-2005 s10 blazer 2wd 8.5 rear, (M50,GU6)
So... for example if you are looking for a 8.5 rear end with 3.42 gears and posi, you can find it in a v6 blazer 2wd with a manual 5spd trans...
There are also 8.5 rear ends in 4x4 s10's but i did not list them... i can if the majority wants them. Hope this helps find the rear end you want.
01-04-2014, 09:11 AM
#25
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S10 ZR2 3.73 / 4.10 rear end
looking for a used S10 rear end 8.5 with 4.10 or 3.73 gears.
I read that a 4x4 ZR2 rear end is 63" wide between the backing plates is that correct?
Also they had 3.73 and 4.10 gear 8.5 code GT4 or Gt5?
Lsxblaze can you send me or post the S10 blazer 4x4 years and sizes please?
Thanks Guys
Steve
I read that a 4x4 ZR2 rear end is 63" wide between the backing plates is that correct?
Also they had 3.73 and 4.10 gear 8.5 code GT4 or Gt5?
Lsxblaze can you send me or post the S10 blazer 4x4 years and sizes please?
Thanks Guys
Steve
01-24-2014, 01:26 PM
#26
Wow, lots of mis-information in this thread. First off, all V6 5 speed S10's were 3.08 ratio from the factory no matter what, if it was a blazer it was 3.42 and the 98+ had the rear disk. Weather or not you got the 8.5 was dependent on other factors not just the engine/trans. It seems that in my research if you got the towing or heavy duty suspension option along with the V6/5 speed you got the 8.5.
In the 2wd trucks, the only way to get 3.73 or 4.10 was with the 4 banger and no 4 banger engine would get the 8.5 rear, didnt matter if you got ZQ8, or the heavy duty Z85 suspension.
All of the ZR2 trucks/blazers got the 8.5 that was 63" overall which is 4" wider than a std 4wd, and all of the ZR2 axles are 3.73 with the G80 locker.
std 4wd ratio is 3.42 with 3.73 optional. As posted before, the VIN or RPO codes will not tell you if its a 7 5/8 or 8.5. But if its the W L35 V6 with M50 5 speed and the towing package and or heavy duty/increased capacity suspension there is probably a 65-70% chance that its an 8.5.
In the 2wd trucks, the only way to get 3.73 or 4.10 was with the 4 banger and no 4 banger engine would get the 8.5 rear, didnt matter if you got ZQ8, or the heavy duty Z85 suspension.
All of the ZR2 trucks/blazers got the 8.5 that was 63" overall which is 4" wider than a std 4wd, and all of the ZR2 axles are 3.73 with the G80 locker.
std 4wd ratio is 3.42 with 3.73 optional. As posted before, the VIN or RPO codes will not tell you if its a 7 5/8 or 8.5. But if its the W L35 V6 with M50 5 speed and the towing package and or heavy duty/increased capacity suspension there is probably a 65-70% chance that its an 8.5.
02-03-2014, 02:49 AM
#27
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I've got a rearend I pulled out of a 2 door 2wd 99 Blazer. It had disc brakes and it's 3.08 ratio.
Seems like the only sure way to ID which truck/blazer has a 8.5 is to look under the truck...
Seems like the only sure way to ID which truck/blazer has a 8.5 is to look under the truck...
01-10-2015, 10:35 PM
#28
My 98 Blazer 4x4 is 3.42 (GU6) 7.5 open diff.
I have found a 4x2 GU6 8.5 local. Will this be plug and play ?
Interested in throwing a rear assembly with the G80 in as well if I could find one.
I have found a 4x2 GU6 8.5 local. Will this be plug and play ?
Interested in throwing a rear assembly with the G80 in as well if I could find one.
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