The Stovebolt Site Forums The Shop Area Driveline 58 apache 3 speed popping out of gear on the highway

My 1958 Apache standard 3-speed column shift transmission performs great except sometimes on the interstate it pops out of third gear. It easily goes back into gear, but then I feel like I need to hold it in gear. Is this a shifter adjustment problem or is it something in my transmission? It is the original transmission that was rebuilt. Thanks!

I had the same thing in my 59 years ago... Definetely in the transmission, not the linkage. Look for a spare. Now would be a great time to put a 3 speed plus overdrive in.

as daddy says, it's internal, your rebuild wasn't well done, likely the syncros, which I think are no longer available

Bill

Last time I was in Jim Carter's basement he had some NOS synchro assemblies. I got one and my transmission rebuilder also did a trick of some kind on my input shaft to allow more engagement.

Although my Blog post is about the 1940-54 transmission, as they are the most common to have this problem, the same applies to your trans.
My Blog post on this.

Thanks guys. Im going to go sit in my kiddy pool and cry.

Hey Cletis, How do I contact Jim Carter about the synchros. Im familiar with the company. Is there some special way to access the basement? Any help would be appreciated.

We got to tour the facility in conjunction with the
Stovebolt reunion in KC.

I would call them and ask who's minding the used parts.

Popping out of gear is usually the result of wear on the end of the "cluster" gear. The gears do not have much meshing contact to begin with. When I had my trans rebuilt, the shop added groves to the gears to positively lock them in place and prevent the disengagement issue from reoccurring. Look for an old post of mine where I might have explained it better when my memory was more fresh.

When you push in the clutch and unload the gears, they release themselves from the groves and no added notchiness or other unwanted behavior is perceived.

Take cletis's advice: Call Jim Carter. They are extremely helpful, knowledgeable, and friendly.

Many Thanks Guys.

Many Thanks Guys.

I wonder if the "trick" was the same as I described in adding a grove in the gears? The wear that causes the trans to pop out of gear is caused by "gringing" the gears occasionally over the years.

It probably was.

I am happy to announce that after these years of just dealing with it occasionally popping out of third gear, my mechanic says he has fixed it. I have yet to confirm that, but I'm excited. They disassembled my transmission, found hard parts and rebuilt it. Ive been waiting a long time to take this truck on a road trip. I'll let you know how it goes. Great mechanic so my confidence level is high.

Well, it only took 3 years so it was just a short wait. Glad your back with us.

"Although my Blog post is about the 1940-54 transmission, as they are the most common to have this problem, the same applies to your trans."

Dave,

That's great information on how to verify transmission case alignment! Obviously it takes some effort to mount to mount a "last word" type indicator in the input gear as you have done but your method will absolutely facilitate perfect alignment.

Many shop manuals I have seen state that "jumping out of gear" can be attributable to the exact misalignment your information addresses.

Replacing gears and/or synchros in a misaligned transmission will cause the same uneven wear on the new parts and jumping out of gear problem that the parts replacement is trying to correct.