Re: S.O.S. 833 pops out of 3rd without load.
 

It's most likely the fork, Driving around with your hand on the shifter wears them out.

Re: S.O.S. 833 pops out of 3rd without load.
 

When you have the cover off , by hand engage 3rd gear synchro, to see if it goes fully onto the speed gear could have a thrust washer or some other issue preventing full engagement. I agree a worn fork can cause this should be easy to see, measure the fork pad area then the synchro slot width,should be maybe .060-.100 clearence would be my guess. Also how is the fork attached to rail, could be a sheared pin or set bolt. All guesses but hope you find it. Joe

Re: S.O.S. 833 pops out of 3rd without load.
 

Jerry,

Check the 3-4 slider, when you look at the splines, they need to be straight not hour glass shaped. Could be the syncro but remember its purpose is to slow the gear just enough to make the gear change. Also take a look at the pilot bushing, a worn one will allow the imput to walk around, although this usally a high gear issue.

Dirk Olson
5036 B/S

Re: S.O.S. 833 pops out of 3rd without load.
 

Had a T-10 that did the same thing (popped out of 3rd) and it turned out to be the syncros.

Re: S.O.S. 833 pops out of 3rd without load.
 

Before you pull the unit check the 3rd and 4th gear engagement by hand with the side cover off. The slider should feel like it positively clicks into each gear. If 3rd feels different than the other gears you probably are at the root of the problem.Take a look at the 3-4 synchro. Make sure the hub, dog keys and expansion springs are OK and installed properly. Do a quick check on the rollers inside the rear of the input shaft, the front bearing surface of the mainshaft, and the mainshaft endplay and rear bearing. You didn't mention which (18 or 23 spline) trans you have and the 18 spline can be normally pretty noisy and cover up an early bearing problem.

Re: S.O.S. 833 pops out of 3rd without load.
 

18 spline and this thing is giving me headaches.

Got rid of the Lakewood bellhousing, tried the wider brass vs steel shifter forks with different cover plates, installed a brand new shifter, put the older, thicker syncro's in and gained .015" and still had the same problem. Bearing's are fine.

Found out the new expansion rings we were sent were the wrong ones and caused the dog keys to be cocked. Thought the problem was solved. Wrong!

Also tried a new slider, compliments of Brewer, and still have the same problem.

From our local 833 expert's that have stopped by the shop to verify the trans was assembled correctly, all the way to asking Arlan Vandkee's advise, the dog gone transmission is still kicking out of 3rd.

Every part in this transmission is brand spanking new with the exception of the cover plate (tried 3) and tail shaft.

Re: S.O.S. 833 pops out of 3rd without load.
 

Is this a trans repair on an existing past functioning trans/engine combo? I'm asking because if it's a conversion you need to check the crankshaft for a pilot bearing. (bushing)
OE production line automatic mopar cranks may not be machined to accept a pilot bushing and putting a 4 speed behind it without a bushing leaves the input shaft without front support. That usually results in a vibration but I'm thinking maybe on a fresh rebuild the "wobble" is covered up for a while until the front bearing/input rollers wear a bit. You have checked all the synchro assembly and side cover detent areas that I would have been sure was the problem area. Since back in the day the 3-4 synchro hub/sleeve/dogs/springs was serviced as an assembly I never had to check for mismatched components. I don't remember if it was possible but I assume someone verified the hub is not installed backwards or has excessive end play and the correct snap ring is installed. I assume you have good detent action (sleeve/balls/spring) in the side cover when off the trans.

I remember the 18 spline trans having a coarser pitch on the gear teeth than the 23 spline unit but I don't think the wrong gear will mesh with the cluster gear.
You aren't going find a more experienced person than Arlen on these units so unless I am missing something I'd have to compare the new parts with the originals to try to find a bogus piece.

Re: S.O.S. 833 pops out of 3rd without load.
 

Jerry, I have a hurst vertigate that shifts awsome, don't think it will pop out of third on you....don't know about downshifting one of these.....if you want me ship it up to you for free testing, just PM or call me on my cell.

Eric

Re: S.O.S. 833 pops out of 3rd without load.
 

as noted : end play in the counter shaft and mainshaft but pull the cover and check the detent ,if you can shim up the detent spring for more tension (small washers) if it gets better you know what the issue is gmonde

Re: S.O.S. 833 pops out of 3rd without load.
 

Thanks for the offer Eric, but I took Alan's advice and swapped out the ball and detent cover for the later version. Problem solved. Thank you everyone. Giddy up!