Popping out of 4 low.

I have a feeling a rebuild is in my future already as the front output had a little play before the last run. But since my D18 t-case was assembled it has always popped out of 4 low when really getting on it off road (think 4 4k rpm run up a bouncy hill in 24" of snow). For now I have solved this with a bungee to the lever. Would this be caused by something outside of a standard rebuild?

 

Could it be that the linkage is just out of adjustment?

 

It is the dual stick D18. There really isn't any linkage as the levers are connected directly to the shift rods. I guess I should have mentioned that. It is a early CJ5 big bore case though.

 

There is the possibility that one of the shift forks is loose or has moved on the rod, Mine has huge setscrews on the shift forks and then safety wire through the set screw head and around the shift rod.

 

Clicks into gear firmly, maybe. Seems like it's being 'forced' out of gear somehow. You will be on it, and then 'bang' the t-case is in neutral, grab the lever in a hurry and try to jam it back in before you lose momentum R)

 

That is certainly worth looking into, Now that you brought it up I remember when I tore mine down for new bearings the detent springs and balls were all full of crud and did not want to move very good.

 

You could drop the cover pan and see if the gears are engaging all the way with the shift lever in its detent, If there not it could be the shift fork has moved some over time.

 

Check the basic things mentioned plus make sure the shifter boot isn't binding putting pressure on the shifter. Also make sure the body is not hitting the shifter and make sure motor/trans mounts are in real good shape. Have seen where iffy or worn mounts would allow the drivetrain to bounce around causing similar issues. If all that is ok, then check the intermediate for endplay. If the intermediate/idler gear is walking back and forth it can work the slider gear out of place and it can jump out of gear. If that is ok, then disassemble the transfer case and look where the slider gear engages the front output gear. It's common for the splined area inside the slider to wear and the dog teeth on the output gear to wear forcing the slider away from the front output gear under heavy load or on again/off again loading.

 

I had the same issue, it turned out to be a weak poppet spring. It was easy to replace, the hi/lo range spring faces the outside of the jeep, so nothing needed to be move/removed to change it out. They have them at walck's for about a $1. It's an easy thing to try before you dig into it further.

 

No shifter boots installed, and no body rubbing. I'll have to check the other stuff later this summer when the cold goes away.

 

COLD what COLD?R) -12 here yesterday. No garage to work in? I am in th esame boat. Kinda put an end to my jeep stuff for this winter also.

Oops kinda hijacked here. no comments ont he actual problem.