Engine/Transmission (1994 - 1998) Sound like "5th gear nut problem, to you"?

[coadman]

My son was driving our '97 3500 5 speed cummins to town for parts earlier this morning, and called me and said he lost 5th gear. The truck only has 77K miles on it, but from what I've read on here in the past, it probably lost the 5th gear nut. He still had all other gears, but just not 5th gear. Is this everyones opinion, on what probably happened? He was not hauling or towing anything at the time. If it is the 5th gear nut problem, will it hurt to go ahead and drive it the way it is, with just the 4 gears?(I'm in the middle of wheat harvest, and really need this truck!!)

thanks,

coadman

 

[RAndrae]

yep

Yep I would say thats the 5 th gear nut, thats what happened to me, I was just driving and I felt like it just slipped into neutral.

*****FYI get all the upgade stuff from Standard trans and have a shop **THAT KNOWS THAT transmission WITH OUT ANY DOUGHT** rebuild it. I f there is the slightest question to the shops ability buy a complete trans from Standard transmission. believe me i speak from experience. The first rebuild I had done the shop came highly reccomended and they told me the whole story about "oh yeah we have done a mess of those". It blew up. I bought the complete unit, wished I had done that right off. good luck

 

[RT66DOC]

OK to drive it like that, for sure.

 

[WMonroe]

I drove mine for about 500 miles after my 5th gear nut fell off. I ordered the fully splined mainshaft, upgraded nut, some new bearing, and some other things I can't remember right now. Replaced it all myself. Just stack all the gears, synchros, etc in order how they come off the shaft. It's not too bad of a job.

Will

 

[coadman]

I was aware of the "5th gear" possibility, as well as the "KDP" possibility, prior to purchasing this truck. I just never expected to experience the "5th gear" problem, until I was well over 100K and towing a large load, but I guess, you never no. I read where some people replaced the nut and tack welded it, so it wouldnt slip. Being a "farmer", that sounds like the type of "fix" I am familiar with!(LOL) I'll probably drive it the way it is for awhile, I'm kind of busy right now, and dont have the "funds" to tear into the transmission at the present.

coadman

 

[coadman]

What actually happens with the 5th gear nut? Does the nut slide off the shaft, as well as the gear, and settle in the bottom of the transmission case? What causes them from causing more problems, like getting into other gears, etc?(As you can tell, I havent been inside of a transmission before). If I purchase the replacement nut, can I do the repair withour dropping the transmission, by just removing the transfer case? If you wish, direct me to a thread or website explaining how to make the repair,

much obliged,

coadman

 

[MUDDY]

put the nut back on and put 3 small spots on nut to shaft with a wirefeed. wont hurt shaft and nut wont come off by itself again. cost nuthin and easy to do and a good idea for preventative maintainance



several rigs round here have that fix



email harold -- email address removed -- [tdr member hbowers] as he has fixed many 4500s.



ya dont have to pull trans. just remove t-case. gear just rides on the shft loose. try to do asap. a few miles wont hurt but too many miles aint good

 

[NPierce]

My truck did the exact same thing yesterday on my way to dallas, from austin. That was a long ride back at 65mph. :{ How exactly do you fix this 5th gear loss without taking the transmission off? I need this truck for work, and with the highways around here, I need 5th, so a good reliable 5th fix is needed. Please help. THanks

 

[Heepdriver]

Maybe this will help. I did the fully splined shaft and new updated fifth gear nut. You should not just do this and restack the gears as there is an end play measurement that needs to be right, . 002-. 006", for those that want to know. You could as long as the output shaft bearing is ok:

1. remove both drive shafts, and drain trans and t-case.

2. remove t-case

3. support trans, with reliable source, floor jack of good propertion, transmission jack, not bubba he can't hold this with the weight of the motor.

4. remove crossmember and tailshaft housing need 12 point socket I forget which size. lower trans a little watch back of motor to fire wall and fan to shroud for clearance issues.

5. Now you can work on the fifth gear without removing the trans and spot weld or whatever.

Fifth gear nut wrench and 12 point socket as well as parts can be acquired from quad4x4.com. I wish that my output shaft bearing had not been wiped out requieing a full shaft cause he has a up dated gear that has been machined for a bushing.



Hope this helps

 

[coadman]

Thanks for the details!!

Maybe this will help. I did the fully splined shaft and new updated fifth gear nut. You should not just do this and restack the gears as there is an end play measurement that needs to be right, . 002-. 006", for those that want to know. You could as long as the output shaft bearing is ok:

1. remove both drive shafts, and drain trans and t-case.

2. remove t-case

3. support trans, with reliable source, floor jack of good propertion, transmission jack, not bubba he can't hold this with the weight of the motor.

4. remove crossmember and tailshaft housing need 12 point socket I forget which size. lower trans a little watch back of motor to fire wall and fan to shroud for clearance issues.

5. Now you can work on the fifth gear without removing the trans and spot weld or whatever.

Fifth gear nut wrench and 12 point socket as well as parts can be acquired from quad4x4.com. I wish that my output shaft bearing had not been wiped out requieing a full shaft cause he has a up dated gear that has been machined for a bushing.



Hope this helps

Is there a gasket that needs replaced when the rear plate on transmission is removed? Just curious, does transmission and transfer case take the same type fluid? Since this just happened to me last week, I was trying to figure out if I would just replace the nut, tack it, and go on, or if I should maybe install the "TorqueKing Retrofit Kit"? Anybody have any opinions? With only 77,000 miles on transmission, it has been performing nicely, so I didnt want to pull the transmission out for repairs.

thanks,

coadman

 

[coadman]

Thanks for the details!!

Sorry, dont know why it double posted,,so I erased the additional post. I have decided to just order the new splined main shaft from "Standard Transmissions", with the new nut and seal/bearing kit. I have a buddy who told me he would help pull the transmission and install the parts. It may be a couple of weeks as I am cutting wheat, but that are my plans at the present. Will this solve my problem, until I get at least 150,000 miles or so on the truck, then I could expect to do a complete transmission rebuild?

thanks,

coadman

 

[johnjackson]

Drop the transfer case. Put the nut back on as tight as you can. Tack weld with wirefeed welder in several places. Sholuld go well over 200k miles.

john

 

[Heepdriver]

As far s the fluids. the trans and t-case do not take the same fluid. the PTO cover should give you a gm part # and castrol syntorq #. call quad4X4.com and order two 2 QT containers, or go to your local dealer and make them look it up in the service manual. Garbage Motors or Dodge. Do not just trust your parts man especially at the advanced napa zone stores. Fluid is a fully synthetic oil with special additives for the friction material on the blocking rings, in order to shift smoothly and live a long happy life. I beter add as I understand it, I am not the engineer.

As far as the t-case I use a full synthetic mercon dextron III with a dash of high tack oil stabilizer or stp oil treatment.

 

[MWhisenant]

hello... . a friend has my 96 3500 dually pulling a 20 foot enclosed trailer. he reports that 5th gear is now just like neutral. so i guess i have the 5th gear nut problem



in this thread, tom says drive it, no problem. someone else else dont drive it far.



the truck is in lexington and is on the way to knoxville. can he keep rolling?



so replacing the not and a tack weld is a good option? does anyone know a shop in lexington or knoxville or in between that can do that?



any help is appreciated.



mark

 

[coadman]

mark,

I "still" havent replaced mine yet! I have the "new" splined mainshaft, nut, etc, setting in a box in my garage, but havent had the time to do the job. A friend was going to help me do it last week, but his girlfriend ended up having him redo her bathroom for a few days instead. I put 600miles on my pickup just yesterday, hauling a combine header back to KC, sure missed 5th gear on the way home(had to stay in the 65-70 mph range, instead of 75-80) good luck,

Jim