TH400 - hard shift into reverse

[jode]

Well, I was reading in the tech archives (funny, but it’s the first time I have done that in years) and ran into a post where someone asked about a hard clunk they were getting when shifting into reverse (and only when shifting in reverse.) It’s funny how everyone on the forum kinda seems to get on “kicks” where everything is related to a certain thing…the general consensus was that his TH400 10-spline output shaft had worn splines and the slop was coming from that and that it was only a matter of time before his entire drivetrain would be inop. I recall having received that same advice when I had a worn QT chain several years ago…but haven’t heard of anyone running into problems with that 10-spline shaft since, and nobody ever seems to talk about it anymore.
Anyway, obviously aside from the more common things like U-joint slop, differential gear slop, and chain slop, (which you would expect to experience in shifts both into and out of reverse – rather than just into reverse) I had a thought on this guy’s hard shifts into reverse. I was in a local tranny shop the other day, and the owner mentioned a kit for TH400s that reduces “hard reverse shifts,” and, when asked about it, he mentioned that hard shifts into reverse with TH400s is a common problem, and that this kit he had was designed to soften things back up.
Just wondering if anyone here has used one of these kits, and what the results were…GSMIKIE?