I'm in the process of a 4l80 swap. I thought I'd share a few things. It's not a difficult job at all.
These are all the parts you need for the swap other than the trans, converter, driveshaft. Every part in this picture is bone stock except for the wiring harness adapter from pcmforless and the 2 driveshaft yokes. The short oil cooler line is a perfect fit and the long line just needs some bending to be perfect as well. The stock quick disconnects fit the 80 case. Verify this because some 80 cases have a tube that juts out inside the trans, mine was just a simple flare fitting.
I put the empty 4l80 case in and made my measurements. The only body mod required was this notch for the electrical connector.
2005 GTO A4, Master Power T-70 turbo in the rear. 7.13@104 8th mile on 1.76 60ft NT-05's. 580/660 wtq 12 psi. True daily driver, even in the snow.
To get the stock controller to shift the 80 you can make your own adapter out of radio shack parts, there is a sticky for this, or order the harness adapter from pcmforless and have them, or anyone with efilive, not hptuners, tune out the 2 fault codes that will prevent shifting. The harness was $170 and they said they will tune out the codes for $25 if you ship them the TCM.
I couldn't find TCM removal answers in a search so...
The TCM is just behind the hood release latch. 05-06 GTO. To get the cover off loosten the rocker panel cover, remove (2) screws that hold the TCM cover in place and ...bam. There is a "trick" to release the connector. There is a blue tab that must be depressed which allows the gray arm to swing over.
There are a couple of options with the driveshaft. The good news is the length is the same and all you need is a slip yoke and someone who can cut the head of the stock shaft off and swap it. Been done on here for $200. The bad news is my local, Republic Diesel, said he couldn't chuck the shaft up in his lathe to cut it because the 2 halfs dont come apart??? But he said he'd build me a 1 piece for $300. Luckily, Kyle, jax4, sold me a u-joint type flange for the pinion that is a perfect fit. I believe he said it was stock on the late 80's pontiac GTA and Iroc???
Well here we go.
I got the trans, converter, and TCM back Fri. Started the install Sat. I wish I could say its been easy but....it hasn't. I've ran into a few hiccups due to lack of experience with the swap so I hope this helps you guys.
Converter: I'm no pro but I've installed a dozen converters on my own cars. I know there are 3 "steps" to watch for and that the converter should be so close to the pump you can't get your fingers between the two. I could fit my whole fist in there....
Well, unless you have a special converter made for an ls2 to 4l80 swap I guess because I fought with this SOB for an hour just trying to get the converter to seat. I tried everything, even adding extra chamfer to the snout with, dare I say, a grinder. I got a straight edge and started measuring and it was looking like it may have been engaged into the pump the whole damn time. Because when I bolted it all up I had the perfect amount of clearance to the flexplate.
But look at the gap to the pump. Dayum.
Trans bolts: I knew there would be one that wasn't used, but I didn't know there would be a second. After having the entire trans bolted to the engine I pulled it back out to do mods to make that last bolt go in and found that the block isn't drilled for it. I probably read this elsewhere but forgot. What a waste of time. This isn't the bolt on top by the way. You can see that one to the left. It doesn't match up. So there are 3 bolt on the drivers side but only the bottom 2 on the passengers. None up top.
Electrical plug: Looks good, plenty of room. Only thing that has worked out so far. Crossmember not installed yet so it's hanging low.
Gear Select Rod and switch are screwing me bad. I can't believe I didn't check this before I bolted it up, again. Trans is a 92, where is the PRND switch supposed to go? There is no boss for the bolts and the rod is WAY to short. I guess I'll try to swap the rod out with my 4l65. I hope I can get it out without taking the VB off. I hope it fits. I'll still have to make a bracket. WTF??????
This is what I need, 4l65:
This is what I have, 4l80:
This is what needs to fit on there in addition to the shift rod:
$30 Dipstick tube from WIT: Some bending and making a bracket but its better than $100 Lokar IMO. I'm just cheap
My driveshaft builder mentioned 3r when he saw it. I don't know if that was his final answer though? Whatever the hell that means. It's the style that has u-bolt straps. It's a week point for sure. I wonder if it's as strong as the pinion? What'll break next?
I got lucky at WIT. They had one of those rods and it was hard for them to locate. *Only charged me $5. Got it installed without trouble. Just time. Evidently the older style cores, pre 97, dont have the bosses for the switch. I had to make a bracket. Pretty cheesy. More time...that was mon. I spent 7 hours on it today and got it running. I was worried about the driveshaft but it was a perfect fit at 53.5". *Unfortunately it vibrates like a mutha trucker @75. Its very disappointing.
I had to slot out the holes in the crossmember.
I had cut the dipstick tube 5" because it was hitting the firewall and had to cut 5" out of the center of the stick and weld it back together. All that was a mistake. I should have left it alone and just bent a curve in the top
Speedo worked perfectly with the oem 80e sensor. No adjustments there. Haven't changed the shift points from the 65e yet but it shifts ok. *The converter was locking and unlocking on me but just gave up and stayed unlocked. Have no idea why yet. Im not happy or hopeful with how its acting
Great news. I got the vibration fixed by raising the trans 5/8" at the mount bolts.
Here is a shot of the rear, GTA/IROC yoke.
The cannon plug is tight so make sure you beat some extra space in there before the install. Also, a pic of the bracket you need to make for the neutral safety switch if there isn't a boss.
Here is how to make that missing cross member bolt easy. Mount x-member, drill the missing hole to about 7/16. Use the oem bolt but cut the tip off where there are no threads to make it easier to fish through the hole you cut in the frame for the cannon plug. Then use 3 washers as spacers between the frame and x-member because it isn't flat/level in that spot. Looks like this.
Use this protractor to find your angles cheap and easy. Put a socket on the u-joint cap to space it out so it can touch the protrator. With car jacked up and the driveshaft found to be level with the ground, my pinion has 2 degrees up angle and my trans had 4 degrees down angle. Two 1/2" nuts as spacers on the trans mount brought it to 1 degree
I wish I had pic of the actual process. Maybe later.
Now....I can't figure out why my converter lock-up is cycling on and off. I tried to just jump power straight to the solenoid but I don't know which wire? It's not any of these. All this does is ground the solenoid. Power to the solenoid comes from somewhere else.
Any help would be appreciated. I'm tiring to figure out whether the problem is in the tune or in the solenoid itself.
Well i thought i fixed the vibration. It just moved up to 80 instead of 70. That sucks. I recommend doing whatever it takes to keep the oem 2 piece shaft. Im gonna shim the dif down from 2 degrees up angle to 1 degree down and hope that fixes it.
It took me 2 hours to shim the dif down and it made no smurfin differance. Im pissed. Dont know what else to do but junk the new shaft and mod the oem.
I picked up a new lockup solenoid today. I hope that fixes my cycling problem. Im tired of this swap already. I dont like the noise, vibration, overdrive gear ratio sucks. Hpt doesnt know the gear ratios are differant so it displays incorrect stall #'s and sometime gives transmission component slipping code. So far the swap is not worth it
Banshee hood SAP fascia Alpine IVA-W505 Viper alarm Kook's LT's catted mids Cutouts Kooks system Forged 427 ETP 245 62cc heads 10:1 Wiseco pistons Chromed TVS2300 17 lbs boost + meth 4L80E by FLT Detroit True Trac Non-Sponsor 8.8 SCSS 3 pillar & Dash pod Non-Sponsor wires Custom mini tub designed by LSPWR with 315 dr's on factory 18's
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