GCSS

I was hauling my racecar to the track and while going about 65 on the interstate the truck went bam! into neutral....
I thought I tore out the clutch... I found I had the rest of the gears so I went ahead and finished going to the dragstrip (Yeah... I go the racing bug bad!!)
Anyways... I took the tailhousing off today and see that the Chrysler repair nut had already been installed at one time and it had ....again backed off.
The 5th gear looks great... no chips. I am just going to clean it all up and re-tighten it with loctite of course.
There is also a small allen setscrew in this nut and It will be tighten dowm as well.
I heard from the grapevine that there is a way to actually weld on the nut to prevent it from backing off again.
Now I am NOT talking about welding the nut to the shaft, I am saying there is a way that a weld is applied to JUST the nut .
Does anyone out there know the specifics to this procedure??
I really don't want this to happen again. It is not hard to fix, I just don't want to be 1000 miles from home and have it go. I drove from Wisconsin to Kentucky in 4th gear two trucks ago and it makes for a loooooooong ride.
OK Guys.......let's hear it!!
Thanks in advance...
Dave

Box5

The only good way of welding it without welding it to the shaft, is to put a second nut on and weld the nuts together. I ended up welding it to the shaft, because eventually it'll just need a full rebuild with the fully splined mainshaft. here's a pic, i made a thread about welding it if u end up wanting to weld it to the shaft, just search for "welded 5th gear"

GCSS

Well to be honest with you, welding on a shaft such as this ,to me will cause problems.. By welding like you did on the shaft especially on one side, I would tend to think you may have warped the shaft. I am laying odds that if you put a dial indicator on the shaft and turn it,there will be a variation in the readings.
I went out to the shop this morning and looked at the situation. I am considering grinding off the collar on the rear-most part of the repair nut ,torqueing it down,locking down the setscrew,and then adding a second nut and then a spot weld joining the two nuts.
What do you think??

Box5

I welded both sides 180 degrees from each other. It didn't heat up enough internally to warp the shaft. So far it's been fine, It's not the best fix by any means, but it will hold better than the replacement nut alone. The only good fix is the fully splined mainshaft, all the rest are temporary.

GCSS

OK.. the 180 degree... I didn't see the other side of the shaft..
I hoped that is what you did.
What is your opinion on my idea?
BTW... I looked all over and could not find a "53" on my block! boy am I happy!
My 2001 had it and I was never fully at ease.
Now I am trying to find a torque multiplication table. My torque wrench only goes to 150# and the nut's supposed to be 280#.
I am thinking about adding exactly 1 foot to the "fulcrum" points to double the torque.
Later..........

Box5

check my first post at the top about welding a second nut to the first one. Should work pretty good for a temporary fix.

Clayten

Welding 2 nuts is the way to go if you are going to weld.

GCSS

'This is the way I plan to go tomorrow.....
I am going to take the new nut from Chrysler,gring the collar off the rear-most part of the nut till it is flat with the rest of the nut, go ahead and install it with loctite,then add a second nut right behind it (loctited of course),then weld the two nuts together in maybe 3 spots.
This HAS to be a good permanent fix.
Now I can't remember what fluid to put back into this tranny.......
What is the good fluid to put in?

schaef_12

these trannies take syntorq

GCSS

Syntorq ?
Never ever heard of it.
I will be going to the Chrysler Dear tomorrow. they should have the approved fluid there.
If there is something better at like NAPA or Advance or Autozone, I will go there. but syntorq?? I can't imagine where I will be able to find that.

Clayten

Ya they like it a lot to you will see when they give you the price. Amsoil makes oil for the nv 4500 as well. The oil has to be a GL 4 rating

Box5

be prepared for a $82 bill for 4 QUARTS of the gl4 nv4500 oil!!

GCSS

I went to Autozone... got a gallon of GL-4 rated 75-90 for like way less than $20.00 seems like it was 3 something a quart.
They called 1 800 lube ????? some 800 number and the guy told her what oil it took.....
I remember them saying GL-4 and the oil was cheap.
Sure I could have spent like $13.00 a quart for synthetic with the GL-4 rating .......but why???
If regular dead dinosaur oil has the GL-4 rating for $3 a quart...why spend more?
I put the new nut on according to the instructions and then welded the "split" on the nut ...just a good Spot weld... they say when it cools down it draws the split together even tighter.
They also said welding the nut to the shaft will break loose in time.
The place I got this info from is a tranny shop Jim Jessup reccomended.
I called the shop and they said the above weld- on -the -split works.
Well.......... got to go ...............
GCSS

Clayten

The information given to you about the welding is correct. And when the weld on the shaft breaks it leaves other future problems with cracking.

wadecool

GCSS, you shouldve been in my garage here in E-town about 9 months ago. We did all that 5th gear fixing, and it was FUN! I will advise you to ONLY put that Castrol Syntorque in your nv4500. There are some other guys here who have posted all the technical reasons. I know it sucks to pay $20 per quart but its cheaper than a new tranny. BTW, I found syntorque at a Chevy dealer for $13 per quart. Chevy used to put the nv4500 5spd in their 3/4 ton & 1 ton trucks, so check some Chevy dealers. Does everybody in Green County still drink Ski? Last time I was there, they sold it everywhere.