Engine rear main seal ?
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From: Concordia Kansas
Car: 1987 Iroc Z 1990 RS 1991 RS
Engine: 454 soon 496
Transmission: Soon T56
Axle/Gears: 308 Posi
Engine rear main seal ?
Okay I can't remember if my friend said 1 piece rear main seal or 2 piece when he got the crate engine that is my car now. I have a 1991 firebird i am parting out. Thats 1 piece right? i know on the T56 swap it matters what flywheel you have. Does it matter what flywheel you have for the T5? Because now I am hoping its 1 piece. If it don't matter then that would be nice to hear but i am afraid thats not true? SO info on this much appreciated. T5 flywheel universal to 1 and 2 piece rear main???
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From: Concordia Kansas
Car: 1987 Iroc Z 1990 RS 1991 RS
Engine: 454 soon 496
Transmission: Soon T56
Axle/Gears: 308 Posi
Re: Engine rear main seal ?
Bump. Just need to know if it will work or not.
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From: Concordia Kansas
Car: 1987 Iroc Z 1990 RS 1991 RS
Engine: 454 soon 496
Transmission: Soon T56
Axle/Gears: 308 Posi
Re: Engine rear main seal ?
I read the T5 conversion and the T56. The only one worried about if it was 1 or 2 piece rear main seal was T56. SO i am going to assume this is correct the T5 will work on my motor if it is 2 piece rear main? And the other engine is 1 piece????? Please help me figure this out so when i get to doing this i don't have my camaro sitting on blocks until i get the money for the flywheel.
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Joined: Mar 2006
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From: CALI
Car: 85' Trans Am !best car ever!
Engine: 305tpi 215hp LB9 two bolt,
Transmission: th-700r4
Axle/Gears: stock (3.27)
Re: Engine rear main seal ?
pretty sure you got a 1 piece seal man. i was read th haynes manual, it says. two piece for 85' and earlier, one piece 86' and later. page 2d-18----2d-19 haynes manual 20 bucks at autozone.
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From: belle fourche,s.d.
Car: '82 z28
Engine: L83 5.7
Transmission: 700r4-1985
Axle/Gears: 3.42 posi
Re: Engine rear main seal ?
original engines are 1 piece rear main seal from '86 up
as stated above,"crate engines" could be either-i think
the old "hecho en mexico"std targetmaster 350s are
two piece rear while all the other crate engines are one
piece.Just have a look under to be sure-the 1 piece fits
into a cast aluminum holder.
as stated above,"crate engines" could be either-i think
the old "hecho en mexico"std targetmaster 350s are
two piece rear while all the other crate engines are one
piece.Just have a look under to be sure-the 1 piece fits
into a cast aluminum holder.
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From: Concordia Kansas
Car: 1987 Iroc Z 1990 RS 1991 RS
Engine: 454 soon 496
Transmission: Soon T56
Axle/Gears: 308 Posi
Re: Engine rear main seal ?
. Its my bible for my car. But being crate I didn't know since I didn't put it in myself. If I did i would know
. So if it was the original motor i wouldn't be asking :P. But its not. Just wondering well I guess I will find out when i pull off the flywheel.But still didnt' answer my question. Will it work if it is 2 piece with the flywheel out of the 91 firebird? Or do i need to be looking for one?
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From: belle fourche,s.d.
Car: '82 z28
Engine: L83 5.7
Transmission: 700r4-1985
Axle/Gears: 3.42 posi
Re: Engine rear main seal ?
the crankshafts are different between 1and 2 piece rear
seals-flywheels/flexplates will not interchange between
the two styles,different bolt pattern and balancing.
seals-flywheels/flexplates will not interchange between
the two styles,different bolt pattern and balancing.
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From: Concordia Kansas
Car: 1987 Iroc Z 1990 RS 1991 RS
Engine: 454 soon 496
Transmission: Soon T56
Axle/Gears: 308 Posi
Re: Engine rear main seal ?
thanks. Thats what i needed to hear to be sure. Well now lets hope my dear friend put a 1 piece rear main engine and not 2 piece. Because that would suck.
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Joined: Mar 2006
Posts: 926
Likes: 1
From: CALI
Car: 85' Trans Am !best car ever!
Engine: 305tpi 215hp LB9 two bolt,
Transmission: th-700r4
Axle/Gears: stock (3.27)
Re: Engine rear main seal ?
sometimes with center bolt valve covers means one piece. outer bolt valve covers is two piece
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From: Concordia Kansas
Car: 1987 Iroc Z 1990 RS 1991 RS
Engine: 454 soon 496
Transmission: Soon T56
Axle/Gears: 308 Posi
Re: Engine rear main seal ?
Yea I found out some info about this to. The early 1 piece rear main was outer bolts and the newer ones have the center bolts. I just hope when i pull out the transmission I will check it out. If not then I guess the camaro will sit until i get some money for a flywheel or a swap.
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Joined: Jan 2009
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From: belle fourche,s.d.
Car: '82 z28
Engine: L83 5.7
Transmission: 700r4-1985
Axle/Gears: 3.42 posi
Re: Engine rear main seal ?
'86 engines have the outer bolt covers while using a 1
piece rear seal,so still have to check if you have outer
bolt covers and engine could be an '86 or crate
piece rear seal,so still have to check if you have outer
bolt covers and engine could be an '86 or crate
Re: Engine rear main seal ?
becareful a buddy of mine rebuilt the 90 heads on the gta while using a 78 block that had a 2 peice.. best thing to do is pull the fly wheel.. if you need a new flywheel just put it back and save... then youve only waisted a weekend
Thread Starter
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From: Concordia Kansas
Car: 1987 Iroc Z 1990 RS 1991 RS
Engine: 454 soon 496
Transmission: Soon T56
Axle/Gears: 308 Posi
Re: Engine rear main seal ?
Yea. I just found out its 1 piece. It has the outer bolts on the valve covers I know that for sure. And just seen a pic of the 2 piece compared to 1 piece Way different. I looked under and looked up between the flywheel and its not even remotely close to a 2 piece
Joined: Dec 2005
Posts: 6,499
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From: Macon, GA
Car: 1992 Camaro RS
Engine: Vortec headed 355, xe262
Transmission: T56
Axle/Gears: 9-bolt 3.70
Re: Engine rear main seal ?
Yeah I was gonna say if you get under there and look you can probably see the flywheel/flexplate mounting flange on the crank and see whether it's a 1 or 2 pc. 1 PC is a big round donut on the back, 2 pc has a goofy shape to it.
Joined: Mar 2000
Posts: 43,187
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
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