gsummers 236 #1 Posted October 6, 2014 Yesterday I bought a 1990 312-8 with a bad axle bearing, was talking to a friend of mine tonight, he has an 8 speed tranny from an older horse that he will sell me cheap, has been rebuilt and never installed, what years used that tranny and are they interchangeable? He thinks it is from a late 70s to an early 80s. Thanks Share this post Link to post Share on other sites
Desko 610 #2 Posted October 6, 2014 There all inter changeable (from what I'm aware of) some hade the brake drum running off the 11/44 gear and some off the cluster shaft if its on the cluster shaft (closest to the front of the trans) it'll drop right in and go. Share this post Link to post Share on other sites
gsummers 236 #3 Posted October 6, 2014 Thanks, I will have to go take a look at it. Share this post Link to post Share on other sites
Desko 610 #4 Posted October 6, 2014 Ok post pictures to! Share this post Link to post Share on other sites
stevasaurus 22,882 #5 Posted October 6, 2014 (edited) You want an 8 speed that has the brake shaft that is on the cluster gear shaft. The hole closest to the front of the tranns. If it is back towards the axle, it is a 6 speed and you will have to mess with the linkage for the brake. All of the 8 speeds that have the brake shaft toward the front (cluster gear shaft) will bolt right on. Why are you not fixing the one you have...may be cheaper...don't throw the old one out. If it is just a bearing and (I would replace all the seals)...you might be talking around $20 to $30 and the time it takes to do what you are going to do anyway...R & R a trans. I do not know what you have in side that trans...rust, bad gears, etc. But if all you have is a bad bearing...fairly easy to fix. Just sayin'... Edited October 6, 2014 by stevasaurus 1 Share this post Link to post Share on other sites
gsummers 236 #6 Posted October 7, 2014 A buddy of mine has a complete tranny he will sell me for $50.00, if it fits I will swap it out and then I will still rebuilt the other tranny. There is a lot of play in the bearing and I am afraid that it will need a new axle, Yes, a rebuild is still optional at this point, just don`t know how bad it is yet. Thanks, Greg Share this post Link to post Share on other sites
Desko 610 #7 Posted October 7, 2014 Just listen to what Stevasuras says and you'll be fine you should watch his videos on how to rebuild a transaxle really informative (id post links but I'm on my phone not my computer) Share this post Link to post Share on other sites
stevasaurus 22,882 #8 Posted October 7, 2014 Thanks Desko...you flatter me. Here is a link to a 6 speed I just did. While not your transmission, the concept is the same. The only real difference is the brake shaft comes out the mushroom gear hole instead of the cluster gear shaft. The differential in yours should be an 8 pinion instead of the 10 pinion in this thread. Click on the video links to take a look. We have some more threads to look at if you need them. Share this post Link to post Share on other sites
gsummers 236 #9 Posted October 12, 2014 New tranny was installed today, seems to work fine, Time will tell. Forgot to take my camera, so no pics of swap out, my bad. 1 Share this post Link to post Share on other sites
