Cummins 4BT & Diesel Conversions Forums banner

4bt to 6r80 trans

7841 Views 35 Replies 11 Participants Last post by  Redark1
I've decided to go another route on my 07 expedition. I've been rolling with a m5r2 trans for the last 5 years and 35k miles and something in the clutch system is not good. I also haven't been able to get 4x4, or cruise control working. So its time to change it up. I'm going with a 6r80 trans which is quite proven in the gasser world. So I have a few questions, I doubt the trans has been put behind a 4bt yet. Ill be machining the adapter plate myself. My current power is probably 225hp...assuming 450tq. The trans is easily rated for this from the 5.4.

Should I use a stock converter to get a baseline for how it will run? Will a stock HD flexplate be good for this application? Will a 5.4 starter start a 4bt?

Trans will be tuned with hp tuner.

Sent from my SM-G970U using Tapatalk
1 - 3 of 36 Posts
I make the adapter for a 6r80 to mate behind a Kubota v2203.

Us shift make a controller for the 6r80 and currently beta testing a 10r80 controller.

I want to build a v2203/10r80 and swap into a jku.

I am following.

Find someone to build you a low stall converter. The stock gas unit is to high.

There is an aftermarket gear reduction mini starter available for the 6r80
How are these transmissions holding up behind the kubota? I am looking at using a 6r80 from the diesel ford ranger here in Australia behind an isuzu 4bd1t, but not sure on the longevity of the tranny. The torque pulses are whats worrying me.

Sent from my SM-G960F using Tapatalk
Alas, no. Hope that's not what I implied. My converter guy is starting with the piece of the 6.0 converter that mates to the 6.0 flexplate.....i believe this will be a forged aftermarket piece. From this he will build it with the proper mating guts that will joint to the 6r. Sorry I'm not up to speed on my converter lingo.

Does that clear it up?

Sent from my SM-G970U using Tapatalk
Are you having a trans built? If so, what mods have been recommended?

Sent from my SM-G960F using Tapatalk
No, im going with a stock trans. I did contemplate a billet input shaft. This trans is rated at i think 490lb torque, and my setup should be right on the brink of that. Nothing ventured, nothing gained.

I plan on using hp tuners to tune the shifting of the 6r.

Sent from my SM-G970U using Tapatalk
Cool, will be interested to see how it holds up.
590lb, or 800nm.
My concern is it lets go when i am in the outback (Australia), i would be putting out similar power with my 4bd1t, 120kw at the wheels. But the torque pulses of the big 4 cylinder is what worries me

Sent from my SM-G960F using Tapatalk
1 - 3 of 36 Posts