Dana 20 jumping out of rear high

[77BroncoTucson]

Finishing up a '77 Bronco build with a 3rd Gen Coyote and 10R80. Kept the Dana 20, with an Advance Adapter for the 10R80 and the Advance Adapter tail housing with a 1350 flange. Changed from the J-shifter to twin stick from Wild Horses. It keeps popping out of rear high!

Am I gonna have to tear this Dana 20 apart and put in stiffer ball detent springs? Everything has to come out of the case to get to them! ARRRRGH! Any ideas? Thanks!

 

[gnpenning]

Have you verified that the shift levers a not hitting the body or anything else??

In order words, are you getting full unrestricted movement? Including the boots causing a problem.

 

[Mark]

On a Dana 20 you don't have to tear the case apart to get to the detent springs. Mine did the same thing to me, I just shimmed the spring a bit to make it stiffer. Did it from the cab, short project.

 

[77BroncoTucson]

The sift levers and linkages are free, though I thought maybe the boot was maybe trying to push both levers back to neutral. Good to know I won't have to tear the case apart! I did put new bearings and seals in it and did not want to have to pry my new seals out. The 10R80 is way longer than the old C4...I hope I won't even have to drop it out. Thanks!

 

[JB Fab]

FYI, setting the rear output pre-load correctly is critical, especially if you have a steep angle on the rear driveline (harmonics). If you replaced the bearings and the preload is insufficient the rear output will not spin true, causing the rear output sliding gear to walk into the neutral position.