retro-roco

iTrader: (1)

Hi,

Need some advice regarding my sons 88 Firebird with 700R4 transmission. Had a small leak from drive shaft seal. We just pulled the engine and transmission, so I took he opportunity to check the tail piece housing. The seal and bushing are worn, so will be replaced. What concerns me is the amount of free play in the mainshaft where it passes from the transmission housing to the tail piece housing. Is it typical that it have significant free play? I would estimate the free play at .0625 to .10 inches. I suspect I've got a bad bearing??

midias

Side to side play is normal although I cannot remember the specs. End play or in and out is not normal, what do you have?

retro-roco

iTrader: (1)

The play that I noticed was vertical, or side to side. there was no noticeable in/out play. I was planning to replace the tail piece bushing, seal and o-ring. but was concerned that the mainshaft free-play might have contributed to the bushing wear...

jmd

iTrader: (4)

You're disassembling an assembly and when it's incomplete (missing parts,) you're questioning radial play.

No. That play doesn't matter until the slip yoke is installed.

retro-roco

iTrader: (1)

The front yoke of the drive shaft is what rides on the bushing, so with the drive shaft removed I noticed the mainshaft free play (that was before I removed the tail piece housing). I was just wanted some input from somebody with a little more experience with the 700R4 than I have (which is NONE!!) Thanks for your help!

Pro Built Automatics

Polish the driveshaft yoke with 600 to 1500 grit sandpaper. Install the Teflon bushing with the groove at the top and use the Vamac 3 lip output shaft seal. These can go 200,000+ miles with no wear or leaks. This will fix any side play you have. If there is a tube on the tailshaft that seals against the yoke, then you will have to replace the seal that is in it.