determining if a tranny is good/bad?

[kyle_22r]

i bought an L series 5 speed a while back.  looks like the typical used toy tranny -- covered in black goo and dirt.  all the forward and reverse gears shift easily back and forth(tranny isn't in a truck or anything).  are there any dead giveaways to if it'd need a rebuild or not?  spinning the input shaft by hand doesn't give me any griding or anything, but i figure that isn't the best way to tell.  gear oil does ooze out of the sealed output bearing when the tranny is tipped on its side though(it happened in the back of my truck on the way home )

[BigMike]

Put a tcase input gear into the output shaft and check for end play and if it wobbles, not the spline contact of the tcase input, but if the actual output shaft of the trans is moving around alot. If it feels good, then the main shaft main bearing should be ok, or at least not dead yet.

Also how firm is the shifter when its in gear? If it has alot of movement when it shouldnt, you might want to replace the socket and seat.

Pull the top cover off, sping the input shaft, and check both the main shaft and the counter shaft for any chipped teath.

Fill some good used oil down the shifter hole, tilt it around a bit to get the oil to move around, and then drain the oil. Then put a screw driver or something in the oil and stirr it like your cooking some mac'n'cheese. If there are any shiny grear stuff in the oil, then that metal from the trans reflecting light from your shop. A bit is ok, but if its like long strings of it on the surface when you stirr it in a circle, then it might have some bad parts in side. Also check for any copper coloring as that would indicate synchro death.

Regarding the input seal, if its not sealing, then its junk. You can stand the tcase on the input shaft and oil would puke out the shifter and breather and never out a good input (or output) seal

[kyle_22r]

i may just wait and have marlin convert it to an L52HD...only thing is that it'll take nearly a month's worth of paychecks for me but it'd be some peace of mind