92 fifth gear gone

[emmettcrocker]

I have a friend with a 92 350 and fifth gear is out, I thought the fifth gear problem was limited to the nv4500 and 92s came with getrag 360. any ideas?

Im going to call her tonight and tell her to crawl under the truck and make sure it isn,t a 4500 for starters.

 

[dpuckett]

Could be something in a shift fork or in that shift rail, too. If it IS a Getrag, have her park it til it can be pulled and the top cover inspected. There may be more inside wrong than you think. Then again, it could be a roll pin out of place.



Keep us updated.



Daniel

 

[emmettcrocker]

Do we have to pull the transmission to figure out whats wrong?

 

[Don Tanklage]

thought you were first gonna decide which trans it was?



if it is a 4500 you will not have to pull it to fix it



don

 

[bgilbert]

Do we have to pull the transmission to figure out whats wrong?

Yep unless you cut a hole in the floor. Then fab a door over the hole.

 

[Don Tanklage]

if it is a 4500 you dont have to go in thru the top



all you will need is a split nut and some red loctite

 

[emmettcrocker]

I know all about the 4500, have one my self and have had it fixed twice first time we went the new nut route and it lasted about 20k then came off again. Next time I had the trans re built including new fully splined main shaft so far its lasted 40k. If its a 4500 I pretty much know what to do but I dont know much about the getrag. This is a beat up unknown milage farm truck so we want to go the low cost route if possible. I hope it is a 4500 at least I know where we stand.

 

[Don Tanklage]

the nut that lasted 20k... i take it that was another stock nut?

 

[MMiller]

If its a getrag, it could be the countershaft dropped too, but that is usually accompanied with lots of slack in the driveline, and bad noises and loss of other gears. I'd think if the shift fork was to blame, that maybe reverse would not work either? At any rate, like the others said-don't drive it, get it figured out before putting it back into service.



Along with the NV4500 discussion here, my brother has the updated mainshaft, and still had the 5th gear nut come off several times. It usually runs 10-15,000 miles and it comes off again. Its currently spot welded.



Michael

 

[Don Tanklage]

Along with the NV4500 discussion here, my brother has the updated mainshaft, and still had the 5th gear nut come off several times. It usually runs 10-15,000 miles and it comes off again. Its currently spot welded.



Michael

i spot welded mine once... see pic - wont ever do that again. i made sure my buddy brake cleaned the heck out of everything and used a gallon of red loctite on mine when he installed the billet kit (yea, the one that had been paid for twice). no probs so far. but then again, when i am towing heavy (20k+) i am usually in 4th over with the 35" tall tires and 1800 rpm and drafting semi's...



dont weld the nut on!

 

[Don Tanklage]

ps - sounds like the earlier 4500's (the ones with the 3/4" dia shifter and the 1 1/4" input shaft) are more durable than the later ones. how can this be? the later ones have a larger input shaft (1 3/8"). has to be stronger. why are they having problems on the input side???



anyone know?



don

 

[dpuckett]

The NV4500s have as stock a 1-1/4" input shaft. You can GET an aftermarket 1-3/8" shaft, but it is spendy. The NV5600s are the ones that have had the different input shaft sizes. The early ones were the same as the 4500; later ones that accompanied the H. O. engine had the 1-3/8".



DP

 

[Don Tanklage]

i dont think so daniel



i believe the early 4500's had the 1 1/4 input and the later ones had 1 3/8 from the factory. supposedly you can identify which you have by the shifter. the early 4500's had a 3/4" dia shifter (up at the top, where the knob screws on) and the later ones had a 5/8 shifter. and from what i hear the later 4500's have input shaft issues. maybe not the shaft itself, but the bearings. i have had no problems (on the input side) with my early 4500



don



ps - what did your friend find when she crawled under her truck? (or is she still down there trying to figure out which trans she has?)



lol

 

[MMiller]

The NV4500s have as stock a 1-1/4" input shaft. You can GET an aftermarket 1-3/8" shaft, but it is spendy. The NV5600s are the ones that have had the different input shaft sizes. The early ones were the same as the 4500; later ones that accompanied the H. O. engine had the 1-3/8".



DP

I agree with this... . NV4500's in CTD application were all the 1 1/4" just like our getrags. There is an aftermaket larger shaft for truck pulling application. Early 6 speeds have a 1 1/4" shaft, first year or so for the HO. Then they went to the larger shaft. Check out Marty1 6 speed conversion here in the first gen forum. He tells about the different 6 speeds.



Michael

 

[BJMarshall]

An NV4500 never came from the factory in a Dodge with a 1 3/8 input. There are a couple of places that offer kits to convert it to that , but it is not stock.

No one makes a billet mainshaft for it either.

 

[Don Tanklage]

An NV4500 never came from the factory in a Dodge with a 1 3/8 input. There are a couple of places that offer kits to convert it to that , but it is not stock.

yea, i think i heard that somewhere before. oh, miller had posted it already



what are you marshal? his 20 minute echo?

No one makes a billet mainshaft for it either.

then what do you call the shaft that the gears go on, not the idler (or what i call the idler, probably got that wrong too), the shaft that is about 5" in dia????



cuz i have a billet one of those in my trans



don

 

[BJMarshall]

No, you don't. Someone may have told you that, but it is inaccurate. How many of these have you rebuilt?
If you have a shaft in there that is 5" in diameter, then you are working on something besides an NV4500.

 

[Don Tanklage]

whats your trip?

 

[BJMarshall]

You should watch the language.
I didn't mean to hurt your feelings and I wasn't trying to rub it in. I didn't notice the other post before I replied.
There are four shafts in an NV4500. Input shaft, countershaft, reverse idler shaft, and the mainshaft which is like an intermediate shaft and output shaft in one. The mainshaft is the one that 5th gear slides on. Except for the area where the 3/4 synchronizer assembly goes, the shaft is nowhere near 5" in diameter.
The countershaft runs under the mainshaft. The early versions had two of the gears pressed on while the newer ones are one piece. The gears are pretty big, but the shaft itself is far 5"
Again, there is no billet shaft replacement for any of these.
I will gladly email you the service manual I have in .pdf format if you will send me an email address.
Don't depend on me to educate you, the material is available, educate yourself so you don't make incorrect comments.

 

[Don Tanklage]

yea, and you should get your facts straight before you start rippin on someone...



i am calling it a main shaft and now you are too, good -



YOU ARE WRONG - A BILLET MAINSHAFT FOR THE 4500 IS READILY AVAIL. i know cuz i have one in my transmission. it didnt come with any gears machined (broached) into it but it is huge. i didnt take a pic of it but this is the stock shaft it replaced: