Verifying info on LS to TH400 flex plate...
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Launching!
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From: Goldsboro/Pikeville NC
Verifying info on LS to TH400 flex plate... i have searched and just want to double verify that the 6.0 flexplate with the spacer will in fact work with my 4.8 to TH400 swap...correct?
http://www.ebay.com/itm/New-OEM-Flyw...ht_2093wt_1185
http://www.ebay.com/itm/New-OEM-Flyw...ht_2093wt_1185
I don't recall if the 4.8 has the +0.400" "long" crank or the short. That kit will work on the short face crank (which is much more common), the short crank is almost flush with the rear cover. Don't forget, you'll need longer bolts too.
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Joined: Jul 2005
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From: Beebe, Arkansas
Look and see if you have the thick flange. It will stick out about almost 1/2'' from rear cover. If so then you will not need the spacer or longer bolts. Just place the flat flex plate on and elongate the TC holes in the flex plate.
The 4.8L standard transmission crank (1225312) is wide/thick. The 4.8L automatic transmission crank (12553482) is a narrow. The wide/narrow crank scenario happened in ’99-’00; after that they all became narrow flange.
The 4.8L standard transmission crank (1225312) is wide/thick. The 4.8L automatic transmission crank (12553482) is a narrow. The wide/narrow crank scenario happened in ’99-’00; after that they all became narrow flange.
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Launching!
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From: Goldsboro/Pikeville NC
im confused as well so i took pictures of my 4.8 with the stock flexplate still installed....from the pictures i took, it looks as if the the crank sits flush with the rear main seal...does this mean i need a spacer?
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From: Beebe, Arkansas
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Joined: Jul 2005
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From: Beebe, Arkansas
That looks like a dished flex plate. You need the spacer after that flex plate to support the verter hub of the Gen I/II trans.
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Launching!
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From: Goldsboro/Pikeville NC
so do i buy the flat flexplate and spacer or do i use my dished flex plate and spacer?
ive searched and could never get a definitive answer on the 4.8
ive searched and could never get a definitive answer on the 4.8
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Joined: Jul 2005
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From: Beebe, Arkansas
All you need to do is buy the spacer or even just the Hughes bushing it is cheaper and rides on the crank flange no need to even un-bolt the dished flex plate, but you still have to elongate and the holes in the flex plate were the verter bolts up. Read the link in my SIG!!!
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Launching!
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Joined: Jul 2012
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From: Goldsboro/Pikeville NC
thank you very much!! you just saved me a few bucks...im just going to buy the hughes spacer and run it..
as far as the flexplate mounting holes go...how much should i open the holes up?
as far as the flexplate mounting holes go...how much should i open the holes up?
I gave you the definitive answer. You have the dished flex plate. Your 4.8L was used infront of a 4l60e.
All you need to do is buy the spacer or even just the Hughes bushing it is cheaper and rides on the crank flange no need to even un-bolt the dished flex plate, but you still have to elongate and the holes in the flex plate were the verter bolts up. Read the link in my SIG!!!
All you need to do is buy the spacer or even just the Hughes bushing it is cheaper and rides on the crank flange no need to even un-bolt the dished flex plate, but you still have to elongate and the holes in the flex plate were the verter bolts up. Read the link in my SIG!!!
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From: Beebe, Arkansas
I would remove the flex plate and use the hughes spacer as a guide to align the flex plate to the converter. Mark and elongate the holes, then reinstall flex plate, use lock tight and torque bolts. Then using RTV or even superglue to temp hold the spacer into the end of the crank till you bolt up the trans and converter.
