What all is required to mate a th350 to a 5.3?
#1
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engine is out of an 04 so i dont think i have the longer crankshaft so i ordered the crankshaft spacer, and longer flexplate bolts. My th350 transmission and stock convertor are ready for pick up and was wondering if there was anything else i may need so i can mate them together?
Also on a dbw tb, where do the nipples hook up too or can i just cap them off. theres one on the lower driver side.?
thanks guys for looking.
Also on a dbw tb, where do the nipples hook up too or can i just cap them off. theres one on the lower driver side.?
thanks guys for looking.
#3
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If you got the crank spacer you will be okay. You have to elongate the wholes a little bit where the converter bolts to the flywheel. not sure on the bolt size because i didnt go with a stock converter mine is a 9.5 inch and i just matched up some bolts and nuts to it. good luck
#5
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if you got the 4l80E flywheel, spacer, and bolts you would have all the right parts-you will have to ck the converter bolt circle though, if you have the small pattern converter, i dont think any holes will line up
what flywheel do you have?
diff converters use diff bolt sizes, you will just have to ck them
what flywheel do you have?
diff converters use diff bolt sizes, you will just have to ck them
#6
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Dished 5.3L flex plate. GM spacer and crank bolts.
Installed like this
![Name: Pic297.jpg
Views: 27715
Size: 27.9 KB](https://ls1tech.com/forums/attachments/conversions-swaps/620413d1501357978-what-all-required-mate-th350-5-3-pic297.jpg)
Spacer GM PART # 12563532
Longer crank bolts GM PART # 12563533
Get Torque converter bolts for the Th350 at napa.
Elongate flex plate holes then install!
Installed like this
![Name: Pic297.jpg
Views: 27715
Size: 27.9 KB](https://ls1tech.com/forums/attachments/conversions-swaps/620413d1501357978-what-all-required-mate-th350-5-3-pic297.jpg)
Spacer GM PART # 12563532
Longer crank bolts GM PART # 12563533
Get Torque converter bolts for the Th350 at napa.
Elongate flex plate holes then install!
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#8
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i may be wrong, but the .400 GM spacer was designed to go bet the crank and flywheel, using the flat flywheel-if the spacer is used like you have it, it might be to far toward the trans, pushing the converter into the pump, unless this is a diff type spacer designed for this purpose
i have seen the round adapters (no bolt on) used on the trans side of the flywheel, i have one on mine now using a TCI 4L80E flywheel-i bolted it right to the crank, then used the spacer to reg the crank to the snout
not trying to confuse the issue
i have seen the round adapters (no bolt on) used on the trans side of the flywheel, i have one on mine now using a TCI 4L80E flywheel-i bolted it right to the crank, then used the spacer to reg the crank to the snout
not trying to confuse the issue
#9
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i may be wrong, but the .400 GM spacer was designed to go bet the crank and flywheel, using the flat flywheel-if the spacer is used like you have it, it might be to far toward the trans, pushing the converter into the pump, unless this is a diff type spacer designed for this purpose
i have seen the round adapters (no bolt on) used on the trans side of the flywheel, i have one on mine now using a TCI 4L80E flywheel-i bolted it right to the crank, then used the spacer to reg the crank to the snout
not trying to confuse the issue
i have seen the round adapters (no bolt on) used on the trans side of the flywheel, i have one on mine now using a TCI 4L80E flywheel-i bolted it right to the crank, then used the spacer to reg the crank to the snout
not trying to confuse the issue
The spacer with the dished dlex plate just supports the hub of the converter. THe Gen III convters have a longer nub on them that slides in to the crank itself. The Gen I th350 converters have the shorter nub the spacer just supports it.
When using the flat flex plate the spacer goes first then flex plate. The hub still slides into the spacer.
Read!
Originally Posted by Bo185
So you have your new Gen III motor and want to run a early auto transmission with it.
There is lots of confusion on this! I need this spacer or that flexplate or this converter.
Really all you need is the right Stock GM flex plate and spacer.
The Gen III/IV has a different crank offset vs the Gen I SBC.
![](http://image.carcraft.com/f/15787574+w750+st0/ccrp_0810_04_z+engine_transmission_swap_gen_3+illustration_position_crankshaft_flange.jpg)
Basically its .400 in. from the were the SBC crank flange location.
So to use the 4l60 with the Gen III GM changed the torque converter by adding a longer nub on the center hub that contacts the crank to support the TC. As well as going with a metric TC spacing.
Gen III converter with long hub
![](http://www.idatc.com/Phots/4l60e_mx_lid.gif)
SBC converter note smaller shorter hub
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101946-00.jpg?t=1267056663)
Gen III engines with a stock 4l60/65/70 GM uses a dished flex plate. Note its the one on the right with the shorter crank bolts. The flat flex plate is on the left note the longer bolts.
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101754-00.jpg?t=1266884737)
On Gen III engines using the 4l80 trans which uses a convter with the Gen I style center hub GM used a Flat flex plate and a spacer mounted between the crank and flex plate. This mounts the TC flush with the center hub and it slides into the spacer to support it.
The flat flex plate has the spacer on the fwd side facing the crank.
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101755-01.jpg?t=1266884768)
Dished 5.3L flex plate mated to a SBC Gen I converter. Note the hub is un supported
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101946-01.jpg?t=1267056721)
Flat 6.0L flex plate and spacer on a SBC converter. Note hub is supported by the spacer.
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101947-00.jpg?t=1267056827)
So you want to bolt your 700r4/TH350/TH400 to a Gen III motor.
Well your in luck!
You have two options using stock GM parts.
1)Use a the dished flex plate and add the spacer after the flex plate. The spacer serves to just support the center of the SBC TC only.
![](http://img.photobucket.com/albums/v518/WildeRacing/Pic297.jpg)
Spacer from GM parts direct or local dealer
GM PART # 12563532
CATEGORY: Engine Flywheel
PACK QTY: 1
CORE CHARGE: $0.00
GM LIST: $52.86
OUR PRICE: $31.34
BOLTS
GM PART # 12563533
CATEGORY: All
PACK QTY: 1
CORE CHARGE: $0.00
GM LIST: $6.86
OUR PRICE: $4.06
2) Use a 6.0L flat flex plate with the spacer between the flex plate and crank. Note:the spacer is part of the flex plate ie its installed onit and should come off with it.
The spacing of the two flex plates when attached to the crank are the same IE the teeth of the both flex plates are in almost the same location. The dish of the 5.3L flex plate makes up for the spacer. So any Gen III starter should work.
![](http://s450.photobucket.com/albums/qq224/Bo185/?action=view¤t=0222101754-01.jpg)
Now you will still have to elongate the flex plate to TC holes as the spacing for the Gen III TC is metric. Not much will be need, test fit it first on the TC.
And from what I have seen you just can't use a Gen III 4l60 TC in an earlier trans.
There is a couple of kickers. Some early 99-2000 4.8L and 6.0L had a longer crank flange to make up for the .400 inches. If your motor happens to be one of these all you need is the flat flex plate and remove the spacer.
And you really have no way of running a DBW TB with a TV cable. Its easier just to use a Gen III trans.
There is lots of confusion on this! I need this spacer or that flexplate or this converter.
Really all you need is the right Stock GM flex plate and spacer.
The Gen III/IV has a different crank offset vs the Gen I SBC.
![](http://image.carcraft.com/f/15787574+w750+st0/ccrp_0810_04_z+engine_transmission_swap_gen_3+illustration_position_crankshaft_flange.jpg)
Basically its .400 in. from the were the SBC crank flange location.
So to use the 4l60 with the Gen III GM changed the torque converter by adding a longer nub on the center hub that contacts the crank to support the TC. As well as going with a metric TC spacing.
Gen III converter with long hub
![](http://www.idatc.com/Phots/4l60e_mx_lid.gif)
SBC converter note smaller shorter hub
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101946-00.jpg?t=1267056663)
Gen III engines with a stock 4l60/65/70 GM uses a dished flex plate. Note its the one on the right with the shorter crank bolts. The flat flex plate is on the left note the longer bolts.
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101754-00.jpg?t=1266884737)
On Gen III engines using the 4l80 trans which uses a convter with the Gen I style center hub GM used a Flat flex plate and a spacer mounted between the crank and flex plate. This mounts the TC flush with the center hub and it slides into the spacer to support it.
![](http://www.idatc.com/Phots/4l80-1-under.gif)
The flat flex plate has the spacer on the fwd side facing the crank.
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101755-01.jpg?t=1266884768)
Dished 5.3L flex plate mated to a SBC Gen I converter. Note the hub is un supported
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101946-01.jpg?t=1267056721)
Flat 6.0L flex plate and spacer on a SBC converter. Note hub is supported by the spacer.
![](http://i450.photobucket.com/albums/qq224/Bo185/0222101947-00.jpg?t=1267056827)
So you want to bolt your 700r4/TH350/TH400 to a Gen III motor.
Well your in luck!
You have two options using stock GM parts.
1)Use a the dished flex plate and add the spacer after the flex plate. The spacer serves to just support the center of the SBC TC only.
![](http://img.photobucket.com/albums/v518/WildeRacing/Pic297.jpg)
Spacer from GM parts direct or local dealer
GM PART # 12563532
CATEGORY: Engine Flywheel
PACK QTY: 1
CORE CHARGE: $0.00
GM LIST: $52.86
OUR PRICE: $31.34
BOLTS
GM PART # 12563533
CATEGORY: All
PACK QTY: 1
CORE CHARGE: $0.00
GM LIST: $6.86
OUR PRICE: $4.06
2) Use a 6.0L flat flex plate with the spacer between the flex plate and crank. Note:the spacer is part of the flex plate ie its installed onit and should come off with it.
The spacing of the two flex plates when attached to the crank are the same IE the teeth of the both flex plates are in almost the same location. The dish of the 5.3L flex plate makes up for the spacer. So any Gen III starter should work.
![](http://s450.photobucket.com/albums/qq224/Bo185/?action=view¤t=0222101754-01.jpg)
Now you will still have to elongate the flex plate to TC holes as the spacing for the Gen III TC is metric. Not much will be need, test fit it first on the TC.
And from what I have seen you just can't use a Gen III 4l60 TC in an earlier trans.
There is a couple of kickers. Some early 99-2000 4.8L and 6.0L had a longer crank flange to make up for the .400 inches. If your motor happens to be one of these all you need is the flat flex plate and remove the spacer.
And you really have no way of running a DBW TB with a TV cable. Its easier just to use a Gen III trans.
Last edited by Bo185; 03-18-2010 at 07:44 PM.
#12
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Ok, that was some good information there.
I am still trying to wrap my head around exactly what I have and exactly what I need to do to mate my motor to my trans.
What I have is a 1999 6.0L and I want to bolt it up to my th-350 trans and th-350 converter. The flexplate on my motor looks like the one pictured on the left so I take it that one is the "flat one". Do these early 6.0L's have the spacer made on-to the back of the crank or is it just sandwitched between the crank and flexplate?
I can see by the pictures that I will have to elongate the TC bolt holes to line them up, thanks for all the pics, that actually helps a lot.
I am still trying to wrap my head around exactly what I have and exactly what I need to do to mate my motor to my trans.
What I have is a 1999 6.0L and I want to bolt it up to my th-350 trans and th-350 converter. The flexplate on my motor looks like the one pictured on the left so I take it that one is the "flat one". Do these early 6.0L's have the spacer made on-to the back of the crank or is it just sandwitched between the crank and flexplate?
I can see by the pictures that I will have to elongate the TC bolt holes to line them up, thanks for all the pics, that actually helps a lot.
#15
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iTrader: (23)
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Not sure where "our" price is, but this place has it for $33 and $3 shipping which isn't bad. They don't seem to have the bolts though.
http://www.gmperformancemotor.com/parts/12563532.html
Gmpartsgiant.com has the the spacer, P/N 11589040, and P/N 12563533 for right at $80 shipped (at least for me), and that seems to be the cheapest I've found all three things from one place. I'm not going to keep digging to save $0.18 more.
http://www.gmperformancemotor.com/parts/12563532.html
Gmpartsgiant.com has the the spacer, P/N 11589040, and P/N 12563533 for right at $80 shipped (at least for me), and that seems to be the cheapest I've found all three things from one place. I'm not going to keep digging to save $0.18 more.
Last edited by chuckd71; 08-12-2010 at 12:45 AM.
#16
Launching!
iTrader: (15)
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did you see this on the last page of this post?
https://ls1tech.com/forums/conversio...l#post13720181
you can get flexplate, spacer, and bolts for 70 shipped from oe parts if you google this part number
https://ls1tech.com/forums/conversio...l#post13720181
you can get flexplate, spacer, and bolts for 70 shipped from oe parts if you google this part number
#18
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did you see this on the last page of this post?
https://ls1tech.com/forums/conversio...l#post13720181
you can get flexplate, spacer, and bolts for 70 shipped from oe parts if you google this part number
https://ls1tech.com/forums/conversio...l#post13720181
you can get flexplate, spacer, and bolts for 70 shipped from oe parts if you google this part number
![Icon Confused](https://ls1tech.com/forums/images/smilies2/icon_confused.gif)