Automatic Transmission Banging into Reverse

[The Axle Doctor]

Hello-

This is a question for the automatic transmission experts out there... I just put a rebuilt TH400 transmission behind the 258 in my CJ7. It shifts up and down properly when Im driving, but when the transmission is warm and I shift out of park and into reverse or drive, It bangs into gear violently. It is severe enough to that I am concerned about it possibly damaging the driveshaft and/or the axle.

I put a new torque convertor and a shift kit into the rebuild... Could the shift kit be causing the severe banging into gear? Again, it only happens when I'm parked and shifting the gear shift out of park. It is fine when I am driving and It also isn't too bad when the transmission is cold.

Thanks-

Jeff

[79cj7duner]

sounds like a healthy shift kit to me. dad has a shift kit in a C-4 in a bronco, it will bark the tires going into reverse.

[xlr8n]

I am no automatic guy but is it possible that the engine idle may be too high? You might try dropping the idle down slightly and see if that makes any difference.

Just a thought.

[FUBAR]

the torque converter is pumping some serious fluid to shift that hard at idle. if your idle is properly set, then i'd be more concerned about the clutch pack wearing out prematurely.

[The Axle Doctor]

I'll keep an eye on it, thats for sure... It didn't seem to quite as bad when I drove it just now, maybe things are wearing in or something... It is pretty fresh off of a rebuild yet. The Torque convertor came from a highly recommended rebuilder and it is a stock unit, so hopefully that isn't going to be a problem.

The idle looks at 700 RPM which sounds and feels right to me.. Good thing, too, because it is a Howell kit and I'm not too sure it it is possible to adjust the idle speed without programming etc.

Thanks for all of the suggestions.. Now I've got to get the pinion angle adjusted on the rear axle to prevent my teeth from vibrating out when Im going down the road. That TH400 really moves things around when you use a D300 rather than the Q/T it was intended for.

Thanks-