Reverse Problem

[ACB]

I have a 92 ch613 with a 13 speed in it. It has started jumping out of reverse. Not real bad empty, but loaded it won't go 20 feet without jumping out of gear. Is this a gear problem of a synchronizer? Thanks for any and all ideas.

[theakerstwo]

I have a 92 ch613 with a 13 speed in it. It has started jumping out of reverse. Not real bad empty, but loaded it won't go 20 feet without jumping out of gear. Is this a gear problem of a synchronizer? Thanks for any and all ideas.

Is that a eaton or mack trans? Mack sure the floor is not toughing the stick and the cab air bag is hold the cab up and not too low.

[peub]

I've been told that a worn shifting fork will cause a transmission to jump out of gear. I don't think heavy truck transmissions have synchronizers. None of the American transmissions anyway. I know that some European manufacturers have them.

[HK Trucking]

I've been told that a worn shifting fork will cause a transmission to jump out of gear. I don't think heavy truck transmissions have synchronizers. None of the American transmissions anyway. I know that some European manufacturers have them.

A 13 speed would have a synchronizer on the hi - lo range shift, but that would have no effect on popping out of reverse.

I concur with Glenns advice, and also would suggest checking for a broken detent spring or stuck detent ball on the reverse - lo shift rail, or possibly the transmission has been abused and the sliding clutch teeth on reverse are so worn that it jumps out of gear under pressure.

Whatever the cause, fix it immediately, as a transmission jumping out of gear under load will send shock waves thru the entire driveline leading to other problems in the future.