Hey Guys, I've got a customer that would like to swap a GM 4L80E transmission into his 1997 Cummins 3/4-ton. The searching that I've done so far has only brought up some very limited info about using an adapter off of a Frito Box truck.
Has anyone done this swap before, or can anyone shed a little more light onto the subject for me? It would be greatly appreciated!!!

Thanks in advance!

Darren Castine
owner, Off Road Innovations
555 Alter St. Suite 19-C
Broomfield, CO 80020
Ph: (303) 410-0802
Fax: (303) 410-0804

First Why? If you are going to change to a chevy tranny why not the Alison 1000?
I have never done it but, The bolt pattern on the tranny should be the same as the Turbo 400. So I would think you could use the adapter from a frito lay truck that was used to mate a turbo 400 to a 4bt. The transmission would also have to be controlled by a stand alone computer. Someone has made this computer for swaps of a cummins into a chevy. I have never found out who or where.
Someone may chime in who has done the chevy cummins conversion.
Good luck

i can think of no reason in the world not to just build up the dodge tranny behind it now. if he is wanting to swap, get a allison from a motor home, they are mated to 5.9 cummins. and forget the 4l80 boat anchore.

4bta with TH400 use different oil pan, oil pan is made of aluminum and and it bolts to flywheel housing, its like support bracket between engine and tranny

First Why? If you are going to change to a chevy tranny why not the Alison 1000?
I have never done it but, The bolt pattern on the tranny should be the same as the Turbo 400. So I would think you could use the adapter from a frito lay truck that was used to mate a turbo 400 to a 4bt. The transmission would also have to be controlled by a stand alone computer. Someone has made this computer for swaps of a cummins into a chevy. I have never found out who or where.
Someone may chime in who has done the chevy cummins conversion.
Good luck


Well, in aswer to the first question, the WHY? is because that's what the customer asked for. I think the Allison swap would be a better bet, and I will probably try to lean him in that direction, but I have seen some 4L80E's stand up to some pretty major abuse too. As far as the bolt pattern, the 4L80E is the same as the 700-R4, not the TH400, unfortunately. The standalone computers for the 4L80E is pretty easy to find, it's mainly the adapters needed that I can't find anywhere. Might just have to go custom...


Darren

Here is a list of parts from Cummins that was used to convert a chevy to cummins. This was compiled by DTT. You may need more or less to do the conversion the other way, not sure. I am sure advanced adapters could help too.

Quantity Part # Description
8 3901395 screw,hex head cap
1 3907701 adapter,crankshaft
1 3908124 transmission adapter
6 3910665 screw.jex flange head
1 3918957 flexplate
1 3923049 ring clamping
2 3910270 dowel pin
6 3913638 hex flange
1 3904181 plug threaded
1 3910248 plug o ring
1 3910260 seal ring
2 3912072 screw
12 3920447 screw
1 3925234 plate,cover

A couple guys said that TCI can hook you up with all of the computer stuff needed to run the trans.

The 4L80E is a truck automatic transmission that was introduced by GM in the early ’90s. It basically uses many of the same internal components as the TH400 but has an overdrive Fourth gear and uses electronics to control shift points, firmness and that sort of thing.
Roughly 75 percent of the 4L80E’s internal parts are interchangeable with a TH400, and the bellhousing bolt pattern and flexplate are the same as the 400. (from HotRod.com)

Here is a list of parts from Cummins that was used to convert a chevy to cummins. This was compiled by DTT. You may need more or less to do the conversion the other way, not sure. I am sure advanced adapters could help too.

Quantity Part # Description
8 3901395 screw,hex head cap
1 3907701 adapter,crankshaft
1 3908124 transmission adapter
6 3910665 screw.jex flange head
1 3918957 flexplate
1 3923049 ring clamping
2 3910270 dowel pin
6 3913638 hex flange
1 3904181 plug threaded
1 3910248 plug o ring
1 3910260 seal ring
2 3912072 screw
12 3920447 screw
1 3925234 plate,cover

A couple guys said that TCI can hook you up with all of the computer stuff needed to run the trans.

Cool - Thanks for this list... I'll check into these part numbers and see exactly where they all go to try to determine what I need vs. what I don't for this swap. Definately a big help...
As for Advance Adapters, I haven't called them direct yet, but as far as the latest catalogs they sent me, they don't list this particular swap. They are usually pretty helpful though, so I will probably call them here in a bit too...

Darren

The 4L80E is a truck automatic transmission that was introduced by GM in the early ’90s. It basically uses many of the same internal components as the TH400 but has an overdrive Fourth gear and uses electronics to control shift points, firmness and that sort of thing.
Roughly 75 percent of the 4L80E’s internal parts are interchangeable with a TH400, and the bellhousing bolt pattern and flexplate are the same as the 400. (from HotRod.com)

Yes, I owe you an apology for that one... I've been dealing with the 4L60E here at the shop alot lately, and that is the one that is the replacement for the 700-R4. My Bad - had a brain fart. The 4L80E IS the replacement for the TH400, you are completely correct!! Thanks for setting me straight :)

Darren

I had to look it up to make sure I had my ducks in a row. I have been known to mix things up too.
Good luck with the swap.