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Am I Loosing My Nut??

1K views 12 replies 5 participants last post by  Saams69 
#1 ·
Well Starting the other day while driving down the highway i was coasting down a hill in 5th gear and my truck popped out of gear. Seems to only do it on the highway when i cost for a period of time or if i get on it and back right out of it. Do you think the nut is coming off of fifth gear? If so do i have to remove the trans to fix this problem or can i do it with it in? :confused013: Thanks for any help.
 
#2 ·
I would say it's a good possibility.

No you do not have to pull the tranny, take both(assuming it's a 4x4) driveshafts off and drop the transfercase. Then you can pull the back cover of the tranny off and it should be obvious to see when you get that far.

Search for the fifth gear nut on here, there may be pics in a thread somewhere.
 
#3 ·
I've had that symptom and I've lost the 5th gear nut. When the nut backs off it just disengages. It won't come back because the gear has slid down the shaft. Some people drive their trucks for months with only 4 forward gears. I Lost 5th gear in ND on the freeway, 70mph, cruise on, and with no noise or warning I was coasting. From what I knew from reading about different failures I just shifted down to 4th and kept on driving (but not at 70mph:hehe:). The next day I was home in TX and a week later had the only correct fix. A fully splined shaft and gear.

A couple transmissions later I had a newly rebuilt transmission installed. It popped out of 5th gear whenever I was going down hill unless I held the shifter in place. That transmission failed 7000 miles later while pulling a heavy trailer through the mountains of Oregon. I'm sorry that I can't tell you what the rebuilder did wrong. By the time I got to a repair shop the transmission was totally trashed.

The short version is more than likely you don't have many miles left on your tranny, especially if you tow.
 
#4 ·
I think it's more of a fluke thing on how long your tranny will last. I've had the nut come off twice on my 96 dually. The first time I just put a stock one back on, ordered an after market nut. By the time the after market nut got there, it had come off again. The after market nut has been holding, and the tranny seems to be fine. I've towed a lot since then. I've also put an after market nut in my 98 and brother's 99. Haven't had a problem since and all 3 trucks have been hooked to the sled a few times. Could any one of the trannys go out tomorrow...sure. So who knows how long it will last. :confused013:

In short, I would just get an after market nut. Here is one place you could get it, or search around.
Dodge Updated NV4500 5th Gear Nut
 
#6 ·
torqmonster, just for clarification did your transmission pop out of 5th when the nut was coming off, then keep on working or did it do like mine did? The two types of failures I am aware of is losing 5th like mine, and the nut breaking and locking up the transmission which happened to a welded nut.

I think drunk on diesel is on the right track.
 
#10 ·
It sounds like your shift fork is wore out or bent. If you drive with your hand resting on the shifter a lot, it will wear and not fully mesh after awhile. I had an old chevy that would do this in 2nd gear. Gets a little scary when you use that gear to hold speed when going down a steep grade and it pops out of gear.
 
#11 ·
I do drive with my hand on the shifter. I think it's either the shift fork or the pad like you guys said. I think I'm just going pull it and build it up in the spring. But first I want to get a turbo and stuff on it. The stock hx35 just crapper out on me. So I won't be driving it for a while. Thanks Alot for all your help. One more question. If you buy the fully splined main shaft do you have to buy a new fifth gear?
 
#12 ·
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