4L80e rebuild and dramas
Thread Starter
Launching!
Joined: Dec 2007
Posts: 256
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From: Geelong, Australia
4L80e rebuild and dramas Hi guys,
I bought an imported 4L80e a few years back and I'm finally getting closer to actually using it. I recently discovered that the output shaft would only turn one direction which caused some concerns. Investigating further, it appears as though this transmission has been apart from someone previously, and not put together properly.
On initial teardown I found several loose bolts in the pan, and most of the frictions missing from within the box itself.
Since then, I've purchased a 'deluxe' overhaul kit and undertaken rebuilding this transmission. All is going well (I hope), but I've come across a potential problem.
The intermediate plate pictured below doesn't appear to fit right. I've put the 4 intermediate frictions and new steels in, but the plate appears to get hung-up on the circlip groove. Looking at google images, this looks like a plate from an older 4L80e. I also need confirmation, but I believe due to the distance between the cooler line fittings I have a 2004+ casing. Can anyone confirm? Is this a mismatch?
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I bought an imported 4L80e a few years back and I'm finally getting closer to actually using it. I recently discovered that the output shaft would only turn one direction which caused some concerns. Investigating further, it appears as though this transmission has been apart from someone previously, and not put together properly.
On initial teardown I found several loose bolts in the pan, and most of the frictions missing from within the box itself.
Since then, I've purchased a 'deluxe' overhaul kit and undertaken rebuilding this transmission. All is going well (I hope), but I've come across a potential problem.
The intermediate plate pictured below doesn't appear to fit right. I've put the 4 intermediate frictions and new steels in, but the plate appears to get hung-up on the circlip groove. Looking at google images, this looks like a plate from an older 4L80e. I also need confirmation, but I believe due to the distance between the cooler line fittings I have a 2004+ casing. Can anyone confirm? Is this a mismatch?
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TECH Regular
Joined: Jun 2013
Posts: 487
Likes: 6
From: Orange, Texas
The year of the case will be on that little yellow tag. First two digits would be the year so "04" would equal 2004 year model. Cooler fittings spread apart means it is a later center lube trans.
The intermediate pressure plate from a 2004 would be flat, I know mine was. The one in your picture is 1998 or earlier I believe.
The intermediate pressure plate from a 2004 would be flat, I know mine was. The one in your picture is 1998 or earlier I believe.
TECH Fanatic
Joined: Jan 2015
Posts: 1,114
Likes: 33
From: Fort Worth, Texas
You have is a 2004 case, You can tell from the sticker, It should have the flat .271" intermediate backing plate like squarles67 said.
But, A earlier counter-bored 4L80E or a TH400 Intermediate plate should still fit the case, Too thick.....Yes, Hang up in the case....No.
You may want to measure from the Snap Ring groove to the last friction to make sure the Flat .271" plate is what you need......There are different height Intermediate Pistons that can throw off the clutch stack height.
It also looks like the Intermediate Sprag race retainer may have been rubbing against piston return spring retainer, '99 & up 4L80E's take a .041" shim under the Sun Gear Bearing, If the shim is left out......The Direct Drum will sit .041" lower in the Case & the sprag race retainer can rub on the spring retainer.
You can also see how much the spring retainer bows on 4L80E's, Using a TH400 spring retainer eliminates that.
But, A earlier counter-bored 4L80E or a TH400 Intermediate plate should still fit the case, Too thick.....Yes, Hang up in the case....No.
You may want to measure from the Snap Ring groove to the last friction to make sure the Flat .271" plate is what you need......There are different height Intermediate Pistons that can throw off the clutch stack height.
It also looks like the Intermediate Sprag race retainer may have been rubbing against piston return spring retainer, '99 & up 4L80E's take a .041" shim under the Sun Gear Bearing, If the shim is left out......The Direct Drum will sit .041" lower in the Case & the sprag race retainer can rub on the spring retainer.
You can also see how much the spring retainer bows on 4L80E's, Using a TH400 spring retainer eliminates that.
