That is good information even though I think the geo metro was responsible for it being DRT. Just kidding. Do you either by chance or for some reason still have the original shaft? That would be interesting to see!! Thanks for sharing.

 

The ebay nut you're showing is what we did for mine the first time. Lasted about 25k. No 5th gear lugging, no towing in 5th gear under 60 mph and it came off while towing at about 70 mph. Had LaserBob do it this time for me and it's supposed to be an improved nut, more so then the first improved nut, but not sure where to find a pic for you. I wouldn't worry about stripping the threads. Torqued it to spec, then put on a cheater bar and gave it another turn.

 

I do believe I have the back half of the shaft on my bench in the shop. Makes quite the paper weight. I'll head out there in a bit.

 

I used the ebay nut on mine the first time and it is a solid design and works well, the second time nut never moved but it destroyed both 5th gears , then i was done and the 5600 went back in.

 

Here's a couple of shots of the back end of the shaft that broke. It's a heavy piece of steel for sure. Rather impressive to be able to break something like that. Note the discoloration and penetraion from the weld and how it broke along the same lines.

 

Yowzah!!

 

Yowzah indeed. I suppose after having fixed a 5th gear issue, and a KDP wound on the same truck, the next 200k miles or so should be uneventful..?

 

Dang.. that is some luck! Hope it remains reliable for ya.

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I'm going to do a fluid change in the nv4500 also.
This transmission has a lot of miles on it and is starting to develop synchro problems, so I'm going to use a process to flush it in an attempt to clean up the synchronizers.
What I'm going to do is a 3 step process I've come up with since nobody seems to have a flush process for the tranny.

I'll ADD 1 quart of MMO (Marvel Mystery Oil) to the fluid that's already in there, run it through all of the gears for 5 or 6 miles until it's warm then drain.
Then I'll refill with 3 quarts Pennzoil synchromesh, 1 quart MMO, drive across town going through all of the gears, then drain. Regular synchromesh fluid is NOT okay to use in the transmission for any length of time because it will sheer down faster than the synthetic, but it will be fine since I'm only using it to flush the transmission.
Drain for the second time, then refill with 5 quarts Redline MT-85 which is a NEW lubricant from Redline designed specifically for the NV4500.
Capacity is 4.25 quarts, I'm going to over fill by 3/4 quart by using 5.

My goal is to remove all of the contamination from previous burnt gear oil and all wear metals that are present in the transmission. The MMO will thin the old fluid that's in there and break surface tension before the initial drain, then it will act as a cleaning agent when combined with fresh synchromesh the second time around.

I will report back and let you know how effective this flush is.
The Redline probably won't be here until the end of the week, so it is a project for next week-end.

 

Well I guess I'll be getting the updated shaft after seeing that!

 

I had an updated mainshaft.......most up to date nut possible.....all the works put about 600 more dollars in tht tranny includeing input shaft.....lasted 8 months nut backed off again.........dont let ne1 tell u ther is a reliable fix, that piece to slip over the splines would b the best tho, ive welded mine all the way around if u do research on metals u know how to weld them, i heated mine up to 450 deg tig welded it all the way around with some 309 and its been a year and a half and i pull my 18,000lb trailer in 5th gear bcause of my 4:10s and have put close to 50,000 miles on tht tranny, ive had my share of metallurgy classes and its my profession dont tell e i cant weld it....