Crank spacer????????
Thread Starter
Joined: Sep 2004
Posts: 3,148
Likes: 12
From: Downers Grove, IL
Crank spacer???????? I want to bolt my 2001 5.3l to a th350 trans. I found the spacer GM pn 12563532 and bolts 12553332 which I believe will work, but I don`t know if I need a new flywheel. According to some posts I need flywheel # 12551367, speartech posted that "You also would need the 6.0L flexplate to go with it." but gm parts direct shows flywheeel #12551367 as being for 4.8l and 6.0l motors Is this the correct flywheel? Transmission center also sells a spacer which goes between the crank and the flywheel but they say you use the stock flywheel. And another post said that the spacer goes on after the flywheel so you can use the stock flywheel. I called a junk yard looking for a 6.0l flywheel and spacer and he said that he thought he had the right part but he also said that the spacer was welded to the flywheel. GM parts direct lists the spacer as a flywheel on one screen and a spacer on another screen so are they one piece or are the flywheel and spacer seperate? 
Has someone used the spacer before, do I need to change my flywheel? and what is the correct part number and application for the flywheel?
Has someone used the spacer before, do I need to change my flywheel? and what is the correct part number and application for the flywheel? All the guys I know just spaced back the converter from the flexplate with washers. How much space do you have between the lugs and the flexplate? You do have an LS1-specific torque converter, right? If not, you'll need one -- the SBC converters don't have the proper pilot on the cover to center the converter in the end of the crankshaft 
I have an aluminum spacer that slips in the back of the crank and fits the hub of the th350/400 converter right in it and centers it.
I got a flexplate that was offset alot more than a stock ls1 flexplate and fit right up against the converter and needed no spacers/washers etc and bolted right up to my th350.
I just dont know which flexplate it was exactly...
I got a flexplate that was offset alot more than a stock ls1 flexplate and fit right up against the converter and needed no spacers/washers etc and bolted right up to my th350.
I just dont know which flexplate it was exactly...
i used spacer 12563532, bolts 12563533, a truck flexplate(my 5.3 flexplate is the same). the spacer bolts on after the flexplate. the spacer is used to hold up the front of the converter(the crank is too short). my converter was a regular sbc reman. unit. i would double check all measurements before final assembly to assure no problems with tranny pump engagement or crank thrust issues.
Thread Starter
Joined: Sep 2004
Posts: 3,148
Likes: 12
From: Downers Grove, IL
Originally Posted by 5.3 racer
i used spacer 12563532, bolts 12563533, a truck flexplate(my 5.3 flexplate is the same). the spacer bolts on after the flexplate. the spacer is used to hold up the front of the converter(the crank is too short). my converter was a regular sbc reman. unit. i would double check all measurements before final assembly to assure no problems with tranny pump engagement or crank thrust issues.
Thank you so much that was exactly what I wanted to hear. Didn`t want to buy a new converter since the th350 will only stay in the car for a year or so. Trending Topics
[QUOTE=G-Body] Thank you so much that was exactly what I wanted to hear. Didn`t want to buy a new converter since the th350 will only stay in the car for a year or so.[/QUOTE
i was using a bop transmission so i was using a tci trans. adapter too, that was why i recommended double checking clearances, just don't want you to have any problems...
Thank you so much that was exactly what I wanted to hear. Didn`t want to buy a new converter since the th350 will only stay in the car for a year or so.[/QUOTEi was using a bop transmission so i was using a tci trans. adapter too, that was why i recommended double checking clearances, just don't want you to have any problems...
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Originally Posted by Brains
All the guys I know just spaced back the converter from the flexplate with washers. How much space do you have between the lugs and the flexplate? You do have an LS1-specific torque converter, right? If not, you'll need one -- the SBC converters don't have the proper pilot on the cover to center the converter in the end of the crankshaft
is it neccessary to use a flywheel from a truck? i am in the progree of an ls1/th400 combo. i currently have a flywheel from a 2002 ls1 from a camaro, and a sbc torque converter. will i be able to use the flywheel that i have or is the truck model different?
thanks,
thanks,
Staging Lane
Joined: May 2006
Posts: 67
Likes: 0
From: Take me to the River..
I too used the aforementioned spacer and bolts. I bought a gen 3 flexplate off ebay.. and it bolted right up to my 200 metric... the outside of the flexplate for the gen 3 motor is offset, which pushes the converter back about a 1/2". Which is where the need for the crank spacer comes in. raptor transmission sells them in a GM box with bolts... i called them and had the box 2 days later....
This flywheel here is a GM PART:
This flywheel allows conversion from the Gen 3 crankshaft to a 700r4. It also has correct hole spacing for a 700r4 application with 298mm torque converter bolt spacing (LS1's require 300mm spacing).
GM Part# 12551367
Its called out in this book here (also a GM Part)
GM PART #88959384 Mandatory MUST HAVE for LS1/6 swap. Has ECM Pin outs, etc. All sortsa goodies inside.
This flywheel allows conversion from the Gen 3 crankshaft to a 700r4. It also has correct hole spacing for a 700r4 application with 298mm torque converter bolt spacing (LS1's require 300mm spacing).
GM Part# 12551367
Its called out in this book here (also a GM Part)
GM PART #88959384 Mandatory MUST HAVE for LS1/6 swap. Has ECM Pin outs, etc. All sortsa goodies inside.
hey turbols6 with this flywheel i bolt up to the ls1 and my 700r4 will bolt right up with my 9/11 converter? i spoke to eric at turbo time and told me to find and ask you since you did what i am doing now. "ls1 into awd ty" i am going to use his ls1 oilpan and motor plates.
thanks
thanks
Originally Posted by Tydriver
This flywheel allows conversion from the Gen 3 crankshaft to a 700r4. It also has correct hole spacing for a 700r4 application with 298mm torque converter bolt spacing (LS1's require 300mm spacing).
GM Part# 12551367
Hmmm thought that was self explanatory.. Guess not..
TECH Fanatic
Joined: Oct 2011
Posts: 1,356
Likes: 2
From: Felton Pa
I went to the local Chevy dealer and asked them about the flexplate and gave them the part number I got from this site "GM Part #12551367". The price was only about $85. I am going to buy one for my 4.8/700r4 combo in a 70 Chevelle.
85 for a spacer? they must have went up since i bought one. hughes, ATI, TCI and other companys have spacers as well. i dont know the current rate, but its got to be lower than 85 bucks.
Thread Starter
Joined: Sep 2004
Posts: 3,148
Likes: 12
From: Downers Grove, IL
The 12551367 part # is for the flat 6.0l 4l80e flex plate. I know that flex plate will bolt up to a 4l80e or TH400 transmission(I have used it on both). I`m not sure if its the same bolt circle as a 700r4. The GM LS1 swap guide has some of its info wrong. In one spot it states that flywheel 12551367 has a 300mm bolt circle and in another it states it has a 298mm bolt circle. I don`t have a 700r4 laying around at the moment so I can`t check what the bolt circle is on it. But I think that the 12551367 is actually a 300mm bolt circle and your 700r4 is a 298mm........
So check your curved flexplate that came with the 4.8L and see if it bolts to your th700r4 (I think it should) If it does pick up spacer GM pn 12563532 and bolts 12553332 (I think the bolts may come with it??? ask the dealer, I never ended up buying one) Put the flywheel on the crank, then the spacer behind it use the longer bolts to attach it and your done.
So check your curved flexplate that came with the 4.8L and see if it bolts to your th700r4 (I think it should) If it does pick up spacer GM pn 12563532 and bolts 12553332 (I think the bolts may come with it??? ask the dealer, I never ended up buying one) Put the flywheel on the crank, then the spacer behind it use the longer bolts to attach it and your done.
Thread Starter
Joined: Sep 2004
Posts: 3,148
Likes: 12
From: Downers Grove, IL
Actually the 4.8L thing just hit me. What year is it? 99-00 with iron heads had a longer crank designed to be used with a flat flexplate only and do not need a spacer.
TECH Fanatic
Joined: Jul 2005
Posts: 1,685
Likes: 7
From: Beebe, Arkansas
Its alittle cheaper to run the 4.8/5.3L curved flex plate and use a spacer vs buying the flat flex plate which comes with a spacer on it.
If the 6.0L flexplate is used it will need to be drilled for the 700r4 as the holes are little farther way than the others. The curved flex plate only needs the holes elongated alittle for use with the 700r4
4.8L/5.3L flexplate on a 700r4 Verter
0222101946-01.jpg?t=1267056721
6.0L flat on same 700r veter
0222101947-00.jpg?t=1267056827
If the 6.0L flexplate is used it will need to be drilled for the 700r4 as the holes are little farther way than the others. The curved flex plate only needs the holes elongated alittle for use with the 700r4
4.8L/5.3L flexplate on a 700r4 Verter
0222101946-01.jpg?t=1267056721
6.0L flat on same 700r veter
0222101947-00.jpg?t=1267056827
