4L80E - Mixing parts from different years
Thread Starter
Launching!
Joined: Dec 2007
Posts: 256
Likes: 0
From: Geelong, Australia
4L80E - Mixing parts from different years Hi Guys,
I need some expert advice again. I purchased a 4L80E from an importer (Australia) many years ago as a "running box, but suit recommend rebuild". A few months after purchase I started to have a look at it and noticed the output shaft wouldn't turn no matter what I tried. I pulled the pan off and found several loose parts (rear fluid tube, servo cover, bolts), which wasn't a good sign. I pulled it apart further and found there were no frictions in the transmission - only steels. At this point I knew I was going to need to rebuild the box. If these were more available in Australia I would have cut my losses and bought another one, but unfortunately they are extremely hard to find and very expensive even in unknown condition.
Over the years when I have time and money to spend, I work on this transmission. A couple of years back I bought a rebuild kit to suit, and have now what I believe to be a 'complete' transmission.
This is where the fun starts. On looking at the year revised components to suit this transmission I appear to have a mixture.
I believe this transmission is from a 2001 express van. (Front and rear cooler lines - LS pattern bellhousing).
I have already replaced the center support as it was clearly incorrect (no feed hole for oil cooler return) with part number U34630EC. This has the required feed hole, but measures flush on the rear. According to my ATSG book, this is a 1997-98 Design Center Support.
I appear to have the following 91-96 components.
Bearing (8623921)
Sun Gear Shaft (Long Bushing Journal)
Sun Gear (Shallow Groove, Bigger Hole)
Rear Ring Gear Shaft (Hollow)
Rear Ring Gear (No Lube Passages)
Installed with what I have, the center support has about 0.090" of shaft journal visible.
Will this combination of parts and clearances work, or do I need to exchange parts and/or shims accordingly? Any help would be greatly appreciated!
I need some expert advice again. I purchased a 4L80E from an importer (Australia) many years ago as a "running box, but suit recommend rebuild". A few months after purchase I started to have a look at it and noticed the output shaft wouldn't turn no matter what I tried. I pulled the pan off and found several loose parts (rear fluid tube, servo cover, bolts), which wasn't a good sign. I pulled it apart further and found there were no frictions in the transmission - only steels. At this point I knew I was going to need to rebuild the box. If these were more available in Australia I would have cut my losses and bought another one, but unfortunately they are extremely hard to find and very expensive even in unknown condition.
Over the years when I have time and money to spend, I work on this transmission. A couple of years back I bought a rebuild kit to suit, and have now what I believe to be a 'complete' transmission.
This is where the fun starts. On looking at the year revised components to suit this transmission I appear to have a mixture.
I believe this transmission is from a 2001 express van. (Front and rear cooler lines - LS pattern bellhousing).
I have already replaced the center support as it was clearly incorrect (no feed hole for oil cooler return) with part number U34630EC. This has the required feed hole, but measures flush on the rear. According to my ATSG book, this is a 1997-98 Design Center Support.
I appear to have the following 91-96 components.
Bearing (8623921)
Sun Gear Shaft (Long Bushing Journal)
Sun Gear (Shallow Groove, Bigger Hole)
Rear Ring Gear Shaft (Hollow)
Rear Ring Gear (No Lube Passages)
Installed with what I have, the center support has about 0.090" of shaft journal visible.
Will this combination of parts and clearances work, or do I need to exchange parts and/or shims accordingly? Any help would be greatly appreciated!
Last edited by SirNemesis; Jun 12, 2020 at 09:22 PM.
TECH Fanatic
Joined: Jan 2015
Posts: 1,114
Likes: 33
From: Fort Worth, Texas
As you already have a the 1st design "Center Lube" Center Support......Buy a Sun Gear Shaft to match & omit the .041" shim. Of course you'll need "Center Lube" Internal Gear, Sun Gear, Sun Gear Bearing & Main Shaft.
More reference material......https://www.transgo.org/demo/06-45-4...be-Changes.pdf
More reference material......https://www.transgo.org/demo/06-45-4...be-Changes.pdf