I had an issue with 3rd gear where I could actually overshift it. Tonight I pulled tranny and removed top cover. Found the roll pin for the 3-4 shifter fork half out. For testing it tonight I put the pin back in and checked all the others-all good. Reinstall top cover and shifter(out of truck of coarse) and still have the same results. Remove top cover and shift into 3rd with it off and the rail while in 3rd will go too far, like past a detent I can feel. I cannot see anything that would stop this besides a detent of some sort, but wouldnt the same detent stop it from overshifting 4th??? I have rebuilt more eaton FRO17210c's then I care too mention but this little top cover has me stumped. Any help or comments would be great. Thanks DW

 

i had mine shear the roll pin for 1-2 and it would jump the gate too, put in a new roll pin and it was fine, try replaceing the roll pin

 

I found one in the shop and replaced it, same problem. The shift fork is not the problem, atleast I dont think it is. The problem is the rod is moving too far. Thanks DW

 

with it on the trans will it over shift? the sycro's would stop the shift fork also. just another idea?

 

Yes it will. Everything inside looks great. Much better then I expected, the truck was used as a hotshot for 14 years. odo shows 240--- and wasnt working when I purchased it. More info: if I manually push the fork like I am going into 3rd I can feel the detent barely and when I go past this I can see something in the form of a small pin that goes through the rail in front of the fork by the top cover. I assume this should not be able to move this far as to expose this small rod/pin(whatever it is)?? There is no visible wear anywhere on the shift rails or inside the tranny itself. Thanks DW

 

mine took force to move them back and forth, no just "pushing" it, it really poped into place, maybe the de tent spring is broke?

 

Just pulled the rollpin for the shifter fork, slightly bent and cracked. I think I will get all new good quality pins tomorrow and I will check the springs. Thanks for all the replies. DW

 

The shift cover has been problematic with this tranny. Difficult to figure without dismanting cover. Believe entire shift cover is avalaible if can't find pieces needed.

 

A lot of the parts for this tranny are used. I have a similar problem with 2nd gear but I haven't found the cause yet.