Shakey Posted May 24, 2014 Share Posted May 24, 2014 Had my car at the track and mid session lost 3rd and 4th gears. Thought the whole tranny was toast and pulled over onto the grass. Found 1st, second and fifth gear are working. Car is a '71 with a 5 speed replaced by a prior owner. There was no grinding or noise prior to losing the gears. I feel nothing different when I shift into 3rd or 4th gear. Just no power. Sound serious or simple? Quote Link to comment Share on other sites More sharing options...
NewZed Posted May 24, 2014 Share Posted May 24, 2014 Probably the shift fork. Quote Link to comment Share on other sites More sharing options...
Shakey Posted May 24, 2014 Author Share Posted May 24, 2014 But would a defective shift fork affect just the 3rd and 4th gears? Quote Link to comment Share on other sites More sharing options...
NewZed Posted May 24, 2014 Share Posted May 24, 2014 Are you on a phone? There's a picture in Post #2. Pretty self-explanatory. Quote Link to comment Share on other sites More sharing options...
Shakey Posted May 24, 2014 Author Share Posted May 24, 2014 Sorry for misunderstanding. Thought he was referring to a clutch fork. Referring to the diagram I see what may be the problem. Thanks. Quote Link to comment Share on other sites More sharing options...
Six_Shooter Posted May 24, 2014 Share Posted May 24, 2014 If you rebuild, do yourself a favour, grab a 4 speed and use the shift forks from it. They are cast iron, unlike the 5 speed that uses aluminum shift forks, at least mine did and any information that I have found about the 5 speed also suggests they all do. I don't recall the designations, but the later 4 speed that is the almost twin to the 5 speed is the one to use.You do need to drill out the roll pin hole in the shift forks to the proper size due to needing to use the 4 speed roll pin, which is larger. It's an easy modification though. I lost 1/2 because the part of the shift fork that wraps around the outside of the shift shaft, had broken away. It had been that way for a long time, I just didn't realize what the problem was because I had been able to drive the car, just getting into 1st was sometimes not easy and it would pop out of 2nd. One day I really yanked for 2nd and lost those two gears and when I pulled it apart, that's what I discovered. Quote Link to comment Share on other sites More sharing options...
NewZed Posted May 25, 2014 Share Posted May 25, 2014 There are so many people out there these days staring at the internet on their tiny phone screens, I just assumed... Rebuilding "while you're at it" could be false economy, the rebuild kits out there aren't fantastic and some seem to have worse new synchros than used Nissan synchros. If it was in good shape you might just replace the main and counter bearings, while you're in there, fix the fork, and put it back together. Just an opinion. You can replace a fork without pulling any gears. Search Hybridz member duragg for a long thread on modifying the transmission for high RPM duty. Lots of detail in that thread. Quote Link to comment Share on other sites More sharing options...
Shakey Posted May 26, 2014 Author Share Posted May 26, 2014 Found the problem. Roll pin holding the fork. Thanks to all. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.