Tranny and Diff Swap. Need Help!
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Joined: Sep 2011
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Car: '82 Berlinetta/'91 Firebird
Engine: 5.0/3.1
Tranny and Diff Swap. Need Help!
Hey Forums!
I am currently looking into a 700r4 transmission, and I have also recently found a rear end out of a 91 s10. With factory 3.42 gears with gm posi, I was wondering if this would fit right in where my stock rear end is without a problem. I am also wondering what you think would be better for a street demon. 3.73s or 4.11s. I have a built 350 ready to roll in. And am looking into either getting my transmission professionally rebuilt or if I should buy the 700r4. Any input would be extremely useful.
Thanks,
LoneMerc
I am currently looking into a 700r4 transmission, and I have also recently found a rear end out of a 91 s10. With factory 3.42 gears with gm posi, I was wondering if this would fit right in where my stock rear end is without a problem. I am also wondering what you think would be better for a street demon. 3.73s or 4.11s. I have a built 350 ready to roll in. And am looking into either getting my transmission professionally rebuilt or if I should buy the 700r4. Any input would be extremely useful.
Thanks,
LoneMerc
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Joined: Oct 2009
Posts: 369
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From: Washington-state
Car: '96 Camaro-Vsux -- SOLD, '84 Z/28
Engine: 3.8L, 305 SBC
Transmission: 4L60E, T-5
Axle/Gears: 3.08s, 3.23s
Re: Tranny and Diff Swap. Need Help!
3.42s aren't that bad for an auto trans car and if you're wanting to make it streetable with good acceleration (depending how much stall you have on torque convert).
I was just at the yard earlier today, and s10 rear ends (along with blazers too) I measured to be 60" from axle flange to axle flange. Our 3rd gen rearends are 62" from axle flange to axle flange.
Also, since its a 91 s10, it should have 28 spline driven axles. Depending on the year of your camaro (which you didn't specify), your carrier could either be a 26 or 28 spline driven axle. Meaning it wouldn't necessarily bolt right up using the internals of the s10 diffy.
I was just at the yard earlier today, and s10 rear ends (along with blazers too) I measured to be 60" from axle flange to axle flange. Our 3rd gen rearends are 62" from axle flange to axle flange.
Also, since its a 91 s10, it should have 28 spline driven axles. Depending on the year of your camaro (which you didn't specify), your carrier could either be a 26 or 28 spline driven axle. Meaning it wouldn't necessarily bolt right up using the internals of the s10 diffy.
Thread Starter
Junior Member
Joined: Sep 2011
Posts: 50
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Car: '82 Berlinetta/'91 Firebird
Engine: 5.0/3.1
Re: Tranny and Diff Swap. Need Help!
Thankyou very much for the reply, My camaro is an 82, and it will have the 28 spline because it is the v8 edition, if I am not mistaken. And will the 2" shortage throw anything off?
Last edited by Lonemerc; Nov 26, 2011 at 08:33 PM.
Joined: Aug 1999
Posts: 19,282
Likes: 103
From: Lawrence, KS
Car: Met. Silver 85 IROC/Sold
Engine: 350 HO Deluxe (350ci/330hp)
Transmission: T-5 (Non-WC)
Axle/Gears: Limited Slip 3.23's
Re: Tranny and Diff Swap. Need Help!
https://www.thirdgen.org/forums/tran...-10-bolts.html
JamesC
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Joined: Oct 2009
Posts: 369
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From: Washington-state
Car: '96 Camaro-Vsux -- SOLD, '84 Z/28
Engine: 3.8L, 305 SBC
Transmission: 4L60E, T-5
Axle/Gears: 3.08s, 3.23s
Re: Tranny and Diff Swap. Need Help!
Yes, the 2" will not fit right in the rearend housing currently on your '82. It's just basically the driven axles will be too short and won't even reach inside the carrier because they're bottom out on the outside of the hub flange.
When I was at the yard, none of the s10 or blazers have torque arms because they all have leaf springs. Leaf springs absorb the rotational torque by the way they're clamped to the rear end. Because our thridgens have coil springs, they need a torque arm so the rear end wont buckle. S10 and blazer rear ends don't even have the bolt holes for the torque arm.
Hopefully you can envision what I'm saying.
Thread Starter
Junior Member
Joined: Sep 2011
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Car: '82 Berlinetta/'91 Firebird
Engine: 5.0/3.1
Re: Tranny and Diff Swap. Need Help!
Hmm makes sense. So looks like im back to the drawing boards on my rear end. I do not have enough money to buy a new rear end, would you recommend buying a used or building mine up with 3.73's posi?
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Joined: Oct 2009
Posts: 369
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From: Washington-state
Car: '96 Camaro-Vsux -- SOLD, '84 Z/28
Engine: 3.8L, 305 SBC
Transmission: 4L60E, T-5
Axle/Gears: 3.08s, 3.23s
Re: Tranny and Diff Swap. Need Help!
If you're buying brand new parts, it will easily turn into close to a grand for new ring and pinion, posi carrier, new driven axles, new bearings/seals. Gets really spendy. You might be able to buy one in a set or something. I would suggest getting a used one and rebuilding one.
Thread Starter
Junior Member
Joined: Sep 2011
Posts: 50
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Car: '82 Berlinetta/'91 Firebird
Engine: 5.0/3.1
Re: Tranny and Diff Swap. Need Help!
Sounds good Rocketyman. I think i will put off on the rear end for now. I am going all out on this 350 and the last thing I want is a weak rear end. Thank-you everyone who helped expand my knowledge on my first Camaro!
Supreme Member
Joined: Dec 2000
Posts: 1,271
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From: stallings,n.c.
Car: 1989 camaro rs convertable
Engine: 305 tbi
Transmission: 700r4
Axle/Gears: 7.5"3.42 gears forth gen 2000 camar
Re: Tranny and Diff Swap. Need Help!
most v6 camaros came with 3.42 rearends.they will bolt right in and are the same strength as the v8 rearends.i have one in my car.
Joined: Jul 2000
Posts: 6,519
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From: Aridzona
Car: `86 SS / `87 SS
Engine: L69 w/ TPI on top / 305 4bbl
Transmission: `95 T56 \ `88 200-4R
Re: Tranny and Diff Swap. Need Help!
Hey Forums!
I am currently looking into a 700r4 transmission, and I have also recently found a rear end out of a 91 s10. With factory 3.42 gears with gm posi, I was wondering if this would fit right in where my stock rear end is without a problem. I am also wondering what you think would be better for a street demon. 3.73s or 4.11s. I have a built 350 ready to roll in. And am looking into either getting my transmission professionally rebuilt or if I should buy the 700r4. Any input would be extremely useful.
Thanks,
LoneMerc
I am currently looking into a 700r4 transmission, and I have also recently found a rear end out of a 91 s10. With factory 3.42 gears with gm posi, I was wondering if this would fit right in where my stock rear end is without a problem. I am also wondering what you think would be better for a street demon. 3.73s or 4.11s. I have a built 350 ready to roll in. And am looking into either getting my transmission professionally rebuilt or if I should buy the 700r4. Any input would be extremely useful.
Thanks,
LoneMerc
91 S-10s were definitely made with 26 splines; some may have had 28 as well.
Gear choice is dependent on transmission and powerband. A low revving stock type 350 won't be helped much by 4.11 gears if they don't match it's powerband. It's hard to go wrong with 3.42 gears; 3.73s work well.
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