Are any TH400 and 4L80 parts interchangable?

[V-10 Killer]

I've heard from a person or two that a 4L80 should be built like a TH400, but do they have any interchangable internals? I'm trying to find a way to get better than a 2.48 first gear and 1.48 second gear. If they are interchangable, does anyone know where I can buy the parts?

[jxaxsxoxn]

The non over drive clutches are the same, the direct drums interchange, the gear train from the center support back interchanges, the bands. 1999 and up front band and apply pin doesn't.
TH400 and 4L80E's have the same gear ratios, I would guess you're looking to install the different aftermarket only ratios commonly offered for the th400 into a 4L80E?

[john kilgore]

Originally Posted by jxaxsxoxn

The non over drive clutches are the same, the direct drums interchange, the gear train from the center support back interchanges, the bands. 1999 and up front band and apply pin doesn't.
TH400 and 4L80E's have the same gear ratios, I would guess you're looking to install the different aftermarket only ratios commonly offered for the th400 into a 4L80E?

the planets are the same except for the hall effect ring on the 4L80 rear carrier. custom ratios can be machined to fit the ring jk

[V-10 Killer]

John, do you know any places specifically that can do that kind of machining?

[john kilgore]

how far from detroit are you? joel at 313 581-6266 or l can do it here in so. cal jk

[V-10 Killer]

I'm probably 2 hours driving from Detroit.

[john kilgore]

Originally Posted by V-10 Killer

I'm probably 2 hours driving from Detroit.

give joel a call YOU WON'T REGRET IT. one smart tranny guy jk