Lost 5th, or my T case is popping out of gear, or both?

[Mike-M]

I have a 7.3, ZF5 and 1356. A couple months ago I was a few hours away from home I killed my transfer case. I was coming down a big hill in 5th, off the throttle completely and it just let go and made a grinding noise. When I got back on the throttle it acted normal, then when i let off again to decelerate, it went out permanently. Being far from home, I took it to a local guy, a friend of a friend :/ rather than paying the few hundred extra to get it towed back to my place. Aside from taking too long, he seemed to have done a good job.

FF to today. Im driving down the road, shift into 5th, and i get nothing but grinding. I go into neutral, and the noise continues, but quietly, until I stop. From a stop I try first, seems fine, second, third, fourth seem fine, until I let off the throttle (in 4th now) and it grinds an feels like it popped out. I grab the transfer case lever, just to see, and when i touched it, it went back into gear. So I do another test, from a stop, holding some pressure on the tcase lever, 1-4 worked, 5th just gave me noise, no power.

What am I looking at here guys? Theres no way I just picked up 2 unrelated drivetrain problems at the same time, right?

 

[typ4]

Sure there is, its a mechanical thing.
Short version, the dumptruck we just did the trans and diff in, now has fuel in the oil form HOPEFULLY injector orings, its a 3406Ecat. The end dump semi tractor that we did one diff in is having wiring issues and the other diff is full of metal.
welcome to my world.
Now if your buddy didnt replace enough parts in your tcase it may still pop out of gear, but that will have no effect on 5th gear UNLESS the rear trans bearing is going away.
So yes, you have 2 separate problems.

 

[79jasper]

Could be the shift fork bushings.
Mine only did it once I went to fourth gear.

 

[Mike-M]

Did some more testing... I think the tcase might be ok. I drove home in 1-4 and was ok. I think its just 5th that doesnt work. It starts grinding when it put it in 5th and the noise doesnt stop even after i take it out of 5th. I have to come to a complete stop to make the grinding sound stop.

 

[Mike-M]

Could be the shift fork bushings.
Mine only did it once I went to fourth gear.

that would be nice if thats all it is. I'll open the top and take a look in there today.

 

[Mike-M]

i had my friend whos a transmission expert diagnose my problem. He says there are clearly multiple problems going on.
1. the second i pushed in the clutch, in my driveway, he says "hear that sound? thats your throw out bearing. youre gonna have problems getting into gear soon" I sort of knew that one but didnt think it was a big deal yet.
2. we get going, get out on an open road, and i shift into 5th and it makes its noise. the noise lessens when i let off the clutch and step on the gas. I do it a couple more times at different rpms for him to hear it. He asks if it has trouble getting into reverse. I tell him it does, and i figured it was the clutch or throw out bearing. He says he guesses the shift forks for 5 and R are breaking and I soon wont have 5 or reverse.
3. it often pops out of 4th when theres no load on it. i got it to do it a few times for him, he says it could be a few things but most likely 4th isnt being held to the output shaft tight enough so it falls out under the right conditions.

Oh and when we got back to my house, i couldnt get it into reverse, even shutting the engine off.
He said to take it out and open it up before i order anything for it though. I also might swap for a model that was behind a 460 cause they have a better gear spread, especially second.