57 3100 rearend choice - The 1947 - Present Chevrolet & GMC Truck Message Board Network

pete57 · 04-11-2013, 11:59 AM

I have a 57 3100 im working on. Ive got my mustang II front from speedway, now I need to get my rearend. Friend of mine has a 79 firebird rear and a 89 iroc Camaro rear both drum breaks. 79 is a little longer than factory 57 and 89 is a little shorter. is one better than the other for transplant? Is there an advantage to running a little longer or shorter? Ill be running 8in vette rallys on all 4 corners and leafspring rear. Thanks..

**G&R's57GMC** · 04-11-2013, 12:05 PM

Get the shorter one

dubie · 04-11-2013, 12:30 PM

i have a shorter one out of a 65 Chevelle and have 8" vette rally's on the back. The rear is 2" narrower than the stock one and I ended up cutting for a small tub because of it. I have a 255 60 R 15 on the back right now but now that it's getting tubbed, I'll put the 275 60's back on

_Ogre · 04-11-2013, 12:47 PM

i run an 86 trans am rearend, which is the same gen III as the 89, 82-92 are similar/same
with the exception of the trans am had disc brakes
look at my build link in my signature, i flipped the axle on top of stock springs
8'' rims on back with 4 in back space. i'd rub if i had a wider rearend

pete57 · 04-11-2013, 01:24 PM

Thanks guys. Ill be going with the iroc rear. I thought I may have clearance problems with the longer rear and 8in wheels.
Ogre, did you have to notch your frame to flip your rear, im wanting mine to sit about like yours.

thotfulspot · 04-11-2013, 07:23 PM

Delmo has pictures of a '57 truck in a Porterbuilt dropmember thread on Porterbuilt's website. I asked him and the rear end he uses is 59" from wheel mounting surface to wheel mounting surface. I'm not sure what the back spacing is on the wheels he make so that will affect it.
Posted via Mobile Device

_Ogre · 04-12-2013, 01:23 PM

truk has a 3'' c-notch
if i had to do it again i'd do a 5'' c-notch
i didn't want to raise the bed floor
lots of pics in my build thread

if can get the torque arm with the 89 rearend i'd get it and use it

SCHRUMGMC · 04-12-2013, 06:30 PM

Im not sure what I'd do with my 59 GMC

wick22 · 04-12-2013, 08:44 PM

my 57 has a 65 chevy truck rearend in it with 15*8 wheels with a 275/60/15 28" tire and it works great

SCHRUMGMC · 04-12-2013, 08:57 PM

Why swap Re-ends ?

_Ogre · 04-13-2013, 12:09 PM

Quote:

Originally Posted by SCHRUMGMC

Why swap Re-ends ?

highway gear, posi, upgraded brakes
truk gets 20 mpg with a 350 in it

thotfulspot · 04-12-2013, 09:16 PM

I need a stronger rear end for towing and to handle the extra horsepower of my engine swap.
Posted via Mobile Device

SCHRUMGMC · 04-12-2013, 09:18 PM

That is true, Did not think about that

04-11-2013, 11:59 AM	#1
pete57 Registered User Join Date: Mar 2013 Location: estill springs, tennessee Posts: 74	57 3100 rearend choice I have a 57 3100 im working on. Ive got my mustang II front from speedway, now I need to get my rearend. Friend of mine has a 79 firebird rear and a 89 iroc Camaro rear both drum breaks. 79 is a little longer than factory 57 and 89 is a little shorter. is one better than the other for transplant? Is there an advantage to running a little longer or shorter? Ill be running 8in vette rallys on all 4 corners and leafspring rear. Thanks..

04-11-2013, 12:05 PM	#2
G&R's57GMC Senior Member Join Date: Aug 2010 Location: Shasta Lake, CA. Posts: 1,624	Re: 57 3100 rearend choice Get the shorter one __________________ Glen & Jane's Rides ‘57 GMC NAPCO Long Bed V8 4 speed Bought 2008 7 other cars & trucks , 5 trailers '56 Chevy Long Bed I6, 4 speed Bought 1990 Sold 8.22.2020 ’56 GMC Suburban Pickup V8, 4 speed Hydramatic Bought 1996 Sold 10.11.2020 My Other Tinkerings http://67-72chevytrucks.com/vboard/s...75#post8967275

04-11-2013, 12:30 PM	#3
dubie Registered User Join Date: May 2000 Location: Flin Flon, Manitoba, Canada Posts: 8,853	Re: 57 3100 rearend choice i have a shorter one out of a 65 Chevelle and have 8" vette rally's on the back. The rear is 2" narrower than the stock one and I ended up cutting for a small tub because of it. I have a 255 60 R 15 on the back right now but now that it's getting tubbed, I'll put the 275 60's back on __________________ My name's Tim and I'm a truckaholic My 56 Chevy shop truck build http://67-72chevytrucks.com/vboard/s...d.php?t=562795

04-11-2013, 12:47 PM	#4
_Ogre Registered User Join Date: Jan 2012 Location: Motown Posts: 7,680	Re: 57 3100 rearend choice i run an 86 trans am rearend, which is the same gen III as the 89, 82-92 are similar/same with the exception of the trans am had disc brakes look at my build link in my signature, i flipped the axle on top of stock springs 8'' rims on back with 4 in back space. i'd rub if i had a wider rearend __________________ cool, an ogre smiley Ogre's 58 Truk build how to put your truck year and build thread into your signature shop air compressor timer

04-11-2013, 01:24 PM	#5
pete57 Registered User Join Date: Mar 2013 Location: estill springs, tennessee Posts: 74	Re: 57 3100 rearend choice Thanks guys. Ill be going with the iroc rear. I thought I may have clearance problems with the longer rear and 8in wheels. Ogre, did you have to notch your frame to flip your rear, im wanting mine to sit about like yours.

04-11-2013, 07:23 PM	#6
thotfulspot Registered User Join Date: Jan 2013 Location: Madison, WI Posts: 198	Re: 57 3100 rearend choice Delmo has pictures of a '57 truck in a Porterbuilt dropmember thread on Porterbuilt's website. I asked him and the rear end he uses is 59" from wheel mounting surface to wheel mounting surface. I'm not sure what the back spacing is on the wheels he make so that will affect it. Posted via Mobile Device

04-12-2013, 01:23 PM	#7
_Ogre Registered User Join Date: Jan 2012 Location: Motown Posts: 7,680	Re: 57 3100 rearend choice truk has a 3'' c-notch if i had to do it again i'd do a 5'' c-notch i didn't want to raise the bed floor lots of pics in my build thread if can get the torque arm with the 89 rearend i'd get it and use it __________________ cool, an ogre smiley Ogre's 58 Truk build how to put your truck year and build thread into your signature shop air compressor timer

04-12-2013, 06:30 PM	#8
SCHRUMGMC Registered User Join Date: Dec 2012 Location: North Carolina Posts: 4,989	Re: 57 3100 rearend choice Im not sure what I'd do with my 59 GMC __________________ 1971 GMC Sierra 1959 GMC 100

04-12-2013, 08:44 PM	#9
wick22 Registered User Join Date: Nov 2012 Location: travelers rest s.c. Posts: 17	Re: 57 3100 rearend choice my 57 has a 65 chevy truck rearend in it with 15*8 wheels with a 275/60/15 28" tire and it works great

04-12-2013, 08:57 PM	#10
SCHRUMGMC Registered User Join Date: Dec 2012 Location: North Carolina Posts: 4,989	Re: 57 3100 rearend choice Why swap Re-ends ? __________________ 1971 GMC Sierra 1959 GMC 100

04-12-2013, 09:16 PM	#12
thotfulspot Registered User Join Date: Jan 2013 Location: Madison, WI Posts: 198	Re: 57 3100 rearend choice I need a stronger rear end for towing and to handle the extra horsepower of my engine swap. Posted via Mobile Device

04-12-2013, 09:18 PM	#13
SCHRUMGMC Registered User Join Date: Dec 2012 Location: North Carolina Posts: 4,989	Re: 57 3100 rearend choice That is true, Did not think about that __________________ 1971 GMC Sierra 1959 GMC 100



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