I don't seem to have posted a thread here, but figure what the hell I probably should. This isn't 100% done, but it's definitely in progress. It's an 89 Astro that originally had a 700R4 in it. After taking a few of these transmissions out, I decided that I wanted more durability and to ditch the TV cable which would limit my intake selection. I scored the 4L80E I'm using and a US Gear Under drive unit for $150 off Craigslist. Hell of a score from a guy that just wanted it gone. I have a reciept for $2200 for the Under Drive unit alone! That will effectively make my 3.0s 3.73s with this transmission. We'll see what I think of it after I use it some. I've got a long way to get to that point.
First, I started with a lot of measurement, fitting etc. How I determined that the engine was in the right position was I measured the spacing of the engine to dog house both before and after the swap. By it being the same I knew that the trans was in the right spot.
There was no way to use the stock mounts, moving the cross member back is damn near impossible. I decided the best way to deal with this was sister a piece up, make some caps and notch the crossmember for the trans.
This is the first iteration of the brace I made. It turned out to be too short. I had to cut it out and redo it. I guess I should have measured twice.
If you notice, I didn't cut all the way through. The reason for this was I wanted everything to line up, so I started the cuts, welded it up then cut the piece all the way out.
Welded in and ready for cutting. I had been having some welder issues, so it turned out to be really nasty welding. She's strong, just really really ugly.
The really screwy thing is I'm using darn near a stock rod based column shift linkage. It took a lot of tweaking but I found the right configuration totally on accident when trying to fit a floor shifter. She shifts awesome right now.
I had to bend the "7" shaped shift rod some to make everything fit together. I also had to lower the pivot point for the rod that goes to the trans.
This is a photo of me trying to get everything aligned right for the linkage to work. Honestly it didn't work out worth squat, although I could probably fix some of that by adding some washers under the mount. It doesn't seem to matter though, it still shifts awesome.
I used the upper arm, it came with the 80. I tried the T400 one and the 700R4 ones but just couldn't get things to fall into place.
Here you can see it mounted for the final fitment. I ended up capping the ends, reinforcing/grinding on welds and then priming and painting to hide my welding sins. . If you notice I don't have any clearancing in the subframe here. It's not needed for just the 80, however with the under drive I did have to cut a small notch in it for clearances. This box is HEAVY, definitely a 2 man job to install. I could do the 60E myself, next time this has to go in our out I'm getting a transmission jack!
A word about yokes. Due to the under drive and many 4L80Es having fixed yokes at the transmission I decided to use a slip style drive shaft. I ended up getting the rear most half of a 1 ton Chevy truck. I also had to switch from a long pinion yoke back to a short pinion yoke on my 9". Overall I had a ton of hours into doing this, but hopefully someone will be able to get by with a lot less research now due to this being out there.
Right now where I stand with this, I'm fighting the Megashift transmission computer. I'll post some stuff up when I get a chance to on that.
4L80E swap
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Re: 4L80E swap
Cool swap!
Matt
Selah, WA
-96 GMC Safari AWD Hi-Top Conversion -->Stalled 5.3L swap & 5" lift
-74 Ford Bronco -->Far from perfect but mine!
-99 V-10 Ford Super Duty Super Cab 4x4 -->Stock with 285 Cooper ATs
-00 Ford Focus Wagon -->The Red Turd
-95 Ford 24' Class C Motorhome -->My big block sleeper
-07 Can-Am Outlander XT -->My yellow 4x4 quad for work & play
-04 Ski Doo REV Summit -->Still several chassis behind!
No new projects until the current ones are done!
Selah, WA
-96 GMC Safari AWD Hi-Top Conversion -->Stalled 5.3L swap & 5" lift
-74 Ford Bronco -->Far from perfect but mine!
-99 V-10 Ford Super Duty Super Cab 4x4 -->Stock with 285 Cooper ATs
-00 Ford Focus Wagon -->The Red Turd
-95 Ford 24' Class C Motorhome -->My big block sleeper
-07 Can-Am Outlander XT -->My yellow 4x4 quad for work & play
-04 Ski Doo REV Summit -->Still several chassis behind!
No new projects until the current ones are done!