Anyone install a 4L60E/4L80E in a 67-69 Firebird?
 

Did some quick searches and found some comments but wanted to see if any has actually done this swap? If so I'd like to talk to you. Would like to verify if the trans will fit in the tunnel without body modifications and what equipment you purchased to make it all work.

For those that might want to reply and discuss the 200/700 transmissions, I have a 200 now that is bad and didn't care for it. I've researched the 700 and prices from a few vendors but really want to get away from the TV Cable setup. Comments are still welcome just wanted to state up front I have researched those options as well.

I have not done the swap, but have also been researching it. My understanding is that the 4L80e will fit in the trans tunnel without cutting, but may require the use of a BFH to clearance the driver's side for cooling lines.

For anyone interested, I am fairly convinced this is a very doable swap but I have decided to go back to a TH400 for now and might consider this for next year. If anyone has questions about what I found out so far, let me know.

List of things you'll need:

4L80E Transmission (~$700 from local shops / ~$3000 from builders)
- Jakes Performance here in Texas came highly recommended
Computer Controller, looks easy to setup and use but around $700
Chevy Trans to BOP engine Adapter $75
Speedometer Alteration - Seems to be 3 options:
- Electronic Speedometer (Dakota Digital)
- Adapter to convert electrical to mechanical
- Alternate tail shaft that will provide full mechanical
Throttle Position Sensor (TPS) $120

I was told only concerns about fitting it in the stock trans tunnel are making sure there is clearance for the cooling lines. An awesome fellow PY'er called me and mention that the earlier housings have the cooling lines at the front of the trans about mid-way down, about where a 2004R has them however for later cases, I think he said 96 and later they moved one back to the middle of the trans and higher which would make providing clearance for the cooling lines much harder so I would avoid those.

Now I have some newb questions about the TH400 but will post those in another thread.

Good bit of info here, thanks.

I've put a 700-r4 in a '69 Firebird before and iirc the trans tunnel took a few small hits with a hammer to clearance up a bit but other wise installed easily enough.

I currently have a 200-4r in my '69 Firebird and also am unsatisfied with the TV cable stuff so have a 4L60e in the garage waiting to be installed. I just picked up a torque converter for it last Monday. I'm going to use a MicroSquirt (DIYautotune.com) for the controller. They can installed as a standalone transmission controller too.

I can't remember where I saw it but someone is building the 200 without TV cable. I'll try finding it.

HI would suggest selling that bad 200-4R to someone in your Pontiac car club so that hd can use it for his Buick A-body project.

You could also save a few bucks and go with a full manual version of the 4L80. You'd always be up and down shifting though. Just a thought.

https://transmissioncenter.net/shop/...ssion-level-4/

Reviving old thread-considering a 4L80e as a winter/off season 2022 project. How much farther back does tail shaft sit? Are the pre-1996 transmissions the best way to go?

I believe Gary Harrison has.

Is he on this forum?

I had hoped to be a little further along in my rebuild but I do have a fresh 4L80e for my 68 firebird sitting in the garage. I went to Jakes Performance. They advised this is very doable and told me I should be able to avoid any modifications and hassles if I went with the earlier version of the 4L80e. The coolant passages are in same/similar location as the TH400.

Here is a table of all the automatic transmission measurements:

https://transmissioncenter.net/shop/...-measurements/

4L80E 2 WD standard length 32 11/16"

Short tail T 400 28 3/8"

By my math, 4 5/16" longer.

It has been mentioned that the earlier cores have more less clearance problems with cooling line, tunnel clearance than the later ones. There is a kit to use with the later transmissions to help with the clearance problem.

Banjo fittings to go to 6AN hoses on late 4L80E: https://www.ebay.com/itm/16435874270...RoCHyUQAvD_BwE

Good to know - which x-member are you gonna use?

Thanks for the info. Any idea if the HD unit can be used? Also, I assume the adapter plate will add at least another 1/8" - 3/8" so about 4.5" longer?

Also, I read in another thread one has to clearance the trans tunnel a bit to clear trans lines. Do the 90 degree fittings provide the adequate clearance without banging on the tunnel?

The HD originally has the parking brake on the rear of the transmission because the HD trucks have 4 wheel disc brakes. I actually own one of these trucks, but have never taken all the parking brake parts off to see what's under it. I'm still moving stuff from my old house to the new one and using this truck with electric gate, and box body to move, so I can't answer that question.

I've never seen anything in print that you can't use the HD transmission, maybe a call/E mail to Jake's would give you the answer about what parts are different , if any on the HD transmissions.

I did a quick search and found this about output shafts:

https://ls1tech.com/forums/automatic...-variants.html

I also found this, and it says that the HD version is actually a beter candidate because some of the better parts in the transmissions:

https://ls1tech.com/forums/automatic...-4x4-swap.html

I guess I'll be looking for the HD/motorhome versions from here on out....:D

I went with the G-Force cross member...it's a beefy item. In my situation no adapter plate required I've gone with the IA2 block which has both patterns.

If using factory speedometer, how does the speedometer cable adapter work and is the location where it attaches to rear the same as a a TH400? Also, how thick is the bell housing adapter plate?

Which dipstick did you use?

Jake's supplied it with the transmission.

Jegs sells an adapter to go from either a pulse speedometer signal or a GPS signal to mechanical speedometer for just over $300. Wires run from transmission pulse generator to box and a speedometer cable runs to original speedometer. If you don’t want to use the signal from the transmission you can use the GPS that comes with the unit.