'69 4 speed downshift problem
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Joined: Jul 2000
Posts: 84
Likes: 0
From: Raleigh NC
'69 4 speed downshift problem
I have a '69 4 speed that has problems downshifting from 4th to 3rd. It just wont go into 3rd from 4th (no grinding). I have to go over to 2nd and back up to 3rd.
No problems upshifting into 3rd... just downshifting. Double clutching doesnt seem to help either. Is this just a shift linkage adjustment? Any ideas.
No problems upshifting into 3rd... just downshifting. Double clutching doesnt seem to help either. Is this just a shift linkage adjustment? Any ideas.
Pro
Joined: Dec 2003
Posts: 592
Likes: 4
From: Denmark
It sounds like it could be a bad synchromesh. I had the same problem once with a m20, no problem upshifting but couldent get it in second untill i was almost at a complete stop, no grinding either.
If its the linkage you should be able to locate the problem from under the car while somebody shift the gears, no reason to remove the console.
If its the linkage you should be able to locate the problem from under the car while somebody shift the gears, no reason to remove the console.
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
First thing you should check is to see if the clutch is fully engaging...see if you can adjust the clutch linkage just a couple of turns to free up the downshift. The adjustment is on the rod coming out of the firewall near the brake master cylinder.
If it's not the clutch, then check the linkage...it doesn't really sound like it's the linkage, but you can give it a shot...it's very simple...there's a clip holding the shift rods in place, then a lock nut to loosen on the rod itself, then twist the end of the rod...I think you will want to lengthen the rod to get it more aligned toward the 3rd gear.
If that doesn't work then it's time to inspect the tranny. If you don't want to just go ahead and rebuild it then you can try to drain the tranny lube, and replace it with fresh stuff and see if that frees it up...might work...it's happened before.
But it may require a tranny rebuild...sounds like the synchro for the third gear isn't behaving...could have some of it's teeth scratched up or notched...or even broken...you won't know until you open up the side cover. You can open the side cover and use a mirror and flashlight to look inside the tranny case and see what's going on.
If it's not the clutch, then check the linkage...it doesn't really sound like it's the linkage, but you can give it a shot...it's very simple...there's a clip holding the shift rods in place, then a lock nut to loosen on the rod itself, then twist the end of the rod...I think you will want to lengthen the rod to get it more aligned toward the 3rd gear.
If that doesn't work then it's time to inspect the tranny. If you don't want to just go ahead and rebuild it then you can try to drain the tranny lube, and replace it with fresh stuff and see if that frees it up...might work...it's happened before.
But it may require a tranny rebuild...sounds like the synchro for the third gear isn't behaving...could have some of it's teeth scratched up or notched...or even broken...you won't know until you open up the side cover. You can open the side cover and use a mirror and flashlight to look inside the tranny case and see what's going on.
Racer
Joined: Nov 2004
Posts: 432
Likes: 0
From: Granbury TX
Drain the transmission grease and refill, don't just check it for fullness. My 4 speed was hard to shift and the grease had been checked at the oil change place and I was told it was full. However I drained it and I found it to look like MUD and smell like xxxx. It must have been in there since 76. Anyway, it made a real difference in the way it shifted. I was so pleased I drained it two weeks later and replaced it again just to get everything out. It should have a drain plug on the bottom toward the front passenger side.
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