Overdrive for the ‘55: ripped off on ebay
I have previously posted about my plan to upgrade the manual trans in my ‘55 to a 4-speed, overdrive with syncros in first gear using an NP833. Everything seemed to go pretty easy, I just was able to switch transmissions in a day (including new u-joints). The next day I took it for a ride, when I got to 4th gear it made a godawful noise, kind of like some grinding on an empty 55 gallon drum with an angle grinder. I pulled out, took off the side cover, all the gears looked OK. The bearings didn’t feel bad. I messed around with the detents (I though maybe the shifter was pushing 2 gears too close), put it back in, same thing. So I took it back out and swapped the old trans (had to switch the yokes again). By now I’m getting pretty good, I can switch transmissions in about 20 minutes. I email my ebay seller, he had claimed the trans was in good shape and was swapped out for a 350 turbo for “medical reasons”. He said he was selling for a friend and probably couldn’t get the money back. Shipping on the thing was $75, so I didn’t shipping it back would do either of us any good. Finally, I got $100 back out of my $225.
I pulled the input shaft out and found this:
Thats a chewed up roller I’m holding. Turns out the tip of the output shaft rides inside the end of the input shaft, surrounded by rollers. The bearing surface is the shafts themselves, no races.
I think I have similar problem with a NP833, how much play did you see in the input shaft before you pulled it apart?
Comment by Eric — April 8, 2006 @ 6:58 pm
It definitely had some play, how much is hard to say. One symtom is that it will make noise in every gear except 3rd (1:1) where the input and output are locked together. It’s worth pulling it apart right away, On mine, the output shaft tip was much worse than the input shaft bore. The output shaft can be bought “retipped” much cheaper than a new one, but the input has to be bought new. Another option is to get the tip of the input shaft ground undersize and to use oversize rollers. With mine both were bad, so I found a needle bearing with races that could be made to fit ( http://gastiresoil.blogsome.com/2005/12/13/overdrive-for-the-55-the-fix/ ), the input was rough, but not undersize and the output tip was built up with hard chrome. Working on this trans was very difficult, some of the best help I found was at slantsix.org (a version was used in mopars). Let me know if need any other help.
Comment by Administrator — April 9, 2006 @ 5:03 am