Chipped 3rd & 4th Gears

[sir_veza]

Got this news today. 3rd - 29 tooth & 4th - 24 tooth gear chipped.

 

[sir_veza]

After thinking it over - likely the result of the shifter being sloppy and crossing over - original plan was installing a new shifter anyway, but wanted to find the route cause...
Ordered new gears from Brewer's today.

 

[Chryco Psycho]

Usually chipping the teeth would be caused by shifting it very hard or forcing it into gear to fast before the syncro can do its job or worn syncros or the wrong type of oil used [GL5] which is too slippery & prevents the syncros from gripping properly .

 

[sir_veza]

As usual you're right Chryco!
However as a rule I'm not particularly aggressive when shifting (but I do like to light it up now and again). I think I should have moved to a Hurst Competition shifter when the transmission was rebuilt three years ago instead of dolling up the original, as the cross from 2nd to 3rd has never been any great shakes for quite some time and sometimes a little sloppy or would not shift over smoothly at all. (A new Hurst Competition shifter is going on now though). You were right about the synchro and now I'm making sure only GL-4 non synthetic gear oil is used.
Thanks!

 

[geardaddy]

As usual you're right Chryco!
However as a rule I'm not particularly aggressive when shifting (but I do like to light it up now and again). I think I should have moved to a Hurst Competition shifter when the transmission was rebuilt three years ago instead of dolling up the original, as the cross from 2nd to 3rd has never been any great shakes for quite some time and sometimes a little sloppy or would not shift over smoothly at all. (A new Hurst Competition shifter is going on now though). You were right about the synchro and now I'm making sure only GL-4 non synthetic gear oil is used.
Thanks!

ground up engagement teeth can be caused by bad clutch,bad driver,too much endplay, thick floormats etc

 

[geardaddy]

best to replace the blockers (brass) and the sliders also. or you will be doing it again...

 

[sir_veza]

best to replace the blockers (brass) and the sliders also. or you will be doing it again...

Been driving various standard transmission vehicles over 43 years. I'm not new to shifting gears.
I changed the 3/4 Synchro completely. After getting advice and assessing I'm convinced the sloppy shifter wasn't any help but also think the guy who rebuilt my transmission three years ago used an incorrect gear oil.