A tachometer in a P-30

cncsparky wrote:

Daveinet wrote:
I think 2002 and later 2500. The 85 is rated for a higher load than the 4L80E.

Dave, do you have any info or a link to your swap? I'm looking into the same, but have not figured out how to handle the parking brake on the back of the tranny. Will the TH400 park brake bolt up to a 4L80/85E that had one from the factory?

Likely. My coach is front wheel drive, so there is a transfercase hanging off the back of the trans. When I had the trans built, I had them install a short shaft from a TH400 into the back of the 4L85e. The output shafts are interchangable. The bolt pattern on the back of both transmissions is identical. Where you need to get creative is the spacing. I machined a spacer between the trans and the transfercase because the back of the 4L85e is flat, where the TH400 is concave. This means the shaft sticks out farther on the 4L85e. Other than that, its pretty simple. So assuming the parking brake bolts on to the back of the trans (instead of a tail shaft housing) one should be able to just add a spacer and bolt on the brake.