Dragon Slayer
Well-Known Member
I recently transferred a late 80 Truck overdrive gear assembly from an Aluminum case housing into an Early Cast Iron housing to make an OD trans. I have done this before, but I ran into an issue with Reverse gear.
First, if you look at parts manuals, and also Brewers site the implication is reverse gears are all the same.
Passions site implies some pitch changes on reverse gears.
What I know is that the reverse gear from early transmissions with shift fork for reverse have a narrow slot the fork fits in. While the interlock type side cover transmissions with the pin type lever for reverse are wider slotted for the pin. If you try to use an earlier gear the pin can't fit in the slot.
Second, these OD transmission gears have one groove on the reverse gear.
Now, I have seen 3 styles of 1-2/Rev syncro clutch: No groove, 1 groove and even found one with 2 grooves, yet parts manuals imply same part number other then the late model change for the wider strut.
Here is my problem. I left the original reverse gear in, since I am using the cast iron ball&dent side cover. Transmission will not properly engage in reverse. The mesh is so tight it attempts to move the 1/2 clutch engaging first gear as reverse engages (Side cover off doing this manually). So I am going to go back and install the original 1 grooved reverse gear from the OD case, but is there a pitch change also on these gears?
I know there were several changes in Truck trans, from Cast Iron to Al but is there pitch changes in rev gears and clutches and anyone have some data on when changes occurred?
Was a real pain after I had it all together to find reverse not working. Luckily I can just loosen tail housing and spin it to get reverse gear shaft out. Thank in advance.
First, if you look at parts manuals, and also Brewers site the implication is reverse gears are all the same.
Passions site implies some pitch changes on reverse gears.
What I know is that the reverse gear from early transmissions with shift fork for reverse have a narrow slot the fork fits in. While the interlock type side cover transmissions with the pin type lever for reverse are wider slotted for the pin. If you try to use an earlier gear the pin can't fit in the slot.
Second, these OD transmission gears have one groove on the reverse gear.
Now, I have seen 3 styles of 1-2/Rev syncro clutch: No groove, 1 groove and even found one with 2 grooves, yet parts manuals imply same part number other then the late model change for the wider strut.
Here is my problem. I left the original reverse gear in, since I am using the cast iron ball&dent side cover. Transmission will not properly engage in reverse. The mesh is so tight it attempts to move the 1/2 clutch engaging first gear as reverse engages (Side cover off doing this manually). So I am going to go back and install the original 1 grooved reverse gear from the OD case, but is there a pitch change also on these gears?
I know there were several changes in Truck trans, from Cast Iron to Al but is there pitch changes in rev gears and clutches and anyone have some data on when changes occurred?
Was a real pain after I had it all together to find reverse not working. Luckily I can just loosen tail housing and spin it to get reverse gear shaft out. Thank in advance.
