Engine/Transmission (1994 - 1998) 5th gear noise, guesses anyone?

[moparguy]

The wifes new 98 12v 5spd. (124k) has been at our house 2 weeks, most of my spare time has been spent getting it ready to hook to her horse trailer, and now it's got transmission issues.



It was straight piped when we got it. I just insulated the back of the cab and installed a resonator off a 01 and it's much nicer inside.



However, now when the transmission warms up after 5 miles or so, 5th is very noisy, sounds like a gear or bearing going out. We couldn't hear it till I made the cab a little less noisy. I changed the fluid and it had lots of glitter in the bottom of the case and the magnet was well coated with crud.



All other gears are quite, 5th gear nut has been replaced.



Any one have ideas on what the problem may be.



I'm gonna pull the tailshaft this weekend and see if I can spot anything so any advise is very welcome.



Thanks RJR

 

[CumminsPower98]

My 5th gear was a bit noisy but I could only hear it when idling along not applying much power and at lower speeds. My oil was always in great shape. My nut finally fell off so I fixed that and I still had the same sound. Later I pulled it and installed a 6 speed and found that the main shaft on the 5 speed was loose so I think that is where my noise was coming from. You might have a rear counter shaft bearing or other bearing going out by the sounds of it and the metal you have in the oil. Hopefully you will be able to see the problem when you pull the tail housing off.

 

[Forrest]

I'm interested in this one too ...

 

[KYOUNG]

your input shaft bearing is going awayafter the pilot bearing failed

 

[moparguy]

I made a attempt at checking out the 5th gear nut and bearing today. No luck.



It seems the guy that installed the new 5th gear nut on our truck (prior to our buying it) was either part gorilla, or just a retard. After pulling the 2 piece drive shaft, and rear transmission mount, found the bolt heads were rounded to the point that even with a new 12pt socket, only two of the eight bolts would break loose. The rest didn't have enough meat left for the socket to turn.



Not only were the bolts rounded, but to break the two loose I did turn required a 1/2 breakover and all the oop I could manage. Should have been torqued to 40ft. lbs.



So after killing most of the day, I buttoned it back up, added a quart of Lucas transmission snake oil and called it good. When it dies I install a reman with the fully splined mainshaft.



RJR

 

[EGaskamp]

My 5th gear makes alot of noise also. It's always done it though ever since I've had it and it has 214k on the clock right now.

 

[HoleshotHolset]

5th gear in my '98 is noisy too...



It got 'quieter' with the addition of a 4" exhaust, though. :-laf



Matt

 

[AMcKee]

My fifth gear is also noisey, let us know if you solve it please.



Andy