98 k2500 4x4 nv4500 problems

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jaxcob

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Hey everybody, hope you had a great 4th and weekend!
Wife and I managed to get to get the bulk of our things moved over the weekend about 400 miles from southern Illinois to southern Iowa. Had 35 totes in the bed of the Chevy and she drove the accord. Added a bit of air to the bags on the 2500 but seemed to hold things pretty good with the sideboards. Took the interstate (at ~80mph) over to the storage place and got in about 2:30 am Saturday morning. Loaded things up Saturday and did the oil checks and tire pressure and all. Installed a new remflex thick exhaust gasket at that time as well.

In looking the truck over on Sunday morning I noticed fluid there where the tail-housing/5th gear housing bolts up to the trans case with the 10mm 12 point bolts. Could tell there was some splatter down along the gas tank cover so got worried the higher speeds for an extended period of time might've thrown some fluid or something. Honestly at this point we were having to leave and while I was worried there had been nothing the night before to indicate any issues and I didn't have the tools to take the fill plug out or anything. I got my spare 2 qts of gm trans fluid out and put them in the cab with me.

About 2 hours in we stopped for fuel and when i started the truck back up in neutral i could hear it sort of whirling. Pushing in the clutch, the noise went away so I assumed the fluid loss was greater than I previously believed and so added a quart of gm fluid. That sort of quieted it down but the noise was still there and as I was just west of St Louis and still had hours to go, decided to push on. Another 2 hours later I was dealing with there still being noise but the priority was the wife's car tire had decided to let go and I was in the midst of finding a new tire on a Sunday afternoon. I added a 2nd quart and that significantly reduced the noise. pressed on towards the new house.

Got to the new house about 8 and unloaded things. Yesterday(Monday) I was off work for the holiday and decided to do a little sleuthing as the thought of a trans rebuild was a bit better to think about compared to an entire replacement trans. I got my stuff out of the toolbox id left behind due to space constraints and opened the fill plug on the trans. About 2 quarts of dark grey dirty fluid came out and crushed my hopes of low fluid. So now I need to pull the trans and see the extent of the carnage. Hopefully the mainshaft, input shaft, or gears aren't wiped but signs are there that there are major issues.
My question is, if the main or counter shaft is wiped, as that brings a rebuild well over a $1000 and possibly significantly more if gears need replaced or all 3 shafts; would one think it's worth just paying the $2000 for a rebuilt trans with a 2yr/24k mile warranty? So far the best I've seen for that is High Impact. Also at this point there's no cheap replacements on marketplace and I'm trying to factor in the value of the truck and not sink too much money in it so just dropping $2000 on a replacement trans isn't a happy idea.

To reiterate, is it worth possibly just getting a replacement if I start tearing it down and find a bunch of issues? Or is it point of diminishing returns?
 

HotrodZ06

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I rebuilt mine when I got the truck it was pretty expensive then about $700 buying special tools and all, but way cheaper than a reman. I have heard of many reman NV4500s doing the same some in the warranty period and some just after. And I'm sure there are many more doing fine you don't hear about. My choice is always rebuild vs reman, but everyones situation is different.
 

jaxcob

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I rebuilt mine when I got the truck it was pretty expensive then about $700 buying special tools and all, but way cheaper than a reman. I have heard of many reman NV4500s doing the same some in the warranty period and some just after. And I'm sure there are many more doing fine you don't hear about. My choice is always rebuild vs reman, but everyones situation is different.
Where'd you buy the parts? I like how torqueking has pretty much everything but the guy on the phone highly recommended using redline mt85 fluid and that goes against everything I've heard or read.
 

HotrodZ06

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Mostly off of ebay being they are all discontinued from gm, and I've been told the synchronizer friction material falls off if you use anything but the castrol syntorq fluid. The previous owners of mine put regular 80w90 GL5 in it and all the synchros were missing friction material.
 

jaxcob

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Mostly off of ebay being they are all discontinued from gm, and I've been told the synchronizer friction material falls off if you use anything but the castrol syntorq fluid. The previous owners of mine put regular 80w90 GL5 in it and all the synchros were missing friction material.
Well that's not bad. I've been looking at evilbay parts and also Amazon carries the fluid. There's also a guy I talked with today a few hours away that said he only used koyo or timken bearings and charges 1200 for a rebuild with a core. It's tempting but I'm going to set on it for a while and get back into next week. It's a long drive to get a trans but I feel it's worth it. Saving $800 plus not messing with any core charges. I like doing things myself but the baby is due in a few weeks and I don't want the truck to set around half finished.
 

HotrodZ06

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Yeah you will have your hands full. And $1200 might not be much more than you rebuilding it yourself provided it's not extra if it needs shafts or gears.
 

Piratehunter

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Where'd you buy the parts? I like how torqueking has pretty much everything but the guy on the phone highly recommended using redline mt85 fluid and that goes against everything I've heard or read.
I just replaced the fluid in my '97 NV4500 with 110K miles while I rebuilt the engine. the fluid was dark, but no water or metal in it. was having a little issue with the 2-3 shift. used the GM #12346190 75W-85 GL4 Synthetic that the owners manual specified. smoothed out the 2-3 shift. everything I've read claims the GL5 fluid will damage the friction plates. note the Dodge spec for the NV4500 calls for GL5. lots of notes and opinions online about this. I went with the owners manual spec, even though the GM fluid was more expensive.
 

Frank Enstein

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The Redline MT85 fluid was developed specifically for the NV4500.

The needle bearings are on intergalactic back-order. Last I heard there were none of them on the planet.
Fortunately they seldom go bad. They aren't loaded heavily.

I have been waiting on my rebuild kit for Frank for a year and a half. The GM fluid too.

The Torque King filter/cooler and an extra quart or so of fluid is a good idea if you are doing much towing.
 

jaxcob

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The Redline MT85 fluid was developed specifically for the NV4500.

The needle bearings are on intergalactic back-order. Last I heard there were none of them on the planet.
Fortunately they seldom go bad. They aren't loaded heavily.

I have been waiting on my rebuild kit for Frank for a year and a half. The GM fluid too.

The Torque King filter/cooler and an extra quart or so of fluid is a good idea if you are doing much towing.
Who are you sourcing your rebuild kit through?
Riverside gear and Torqueking along with Allstate and some amazon suppliers show the full rebuilds in stock along with being able to find the needle bearings on amazon. amp brand i think. Allstate lists several individual parts for the trans as in stock as does motive gear on amazon.
I'll probably go with the redline mt-85 #50504 when I go to refill the trans because I'm not super happy with the gm fluid being so dark after a year but having no significant metallic pieces in it is a plus.
I've looked at the filter and cooler kits but as it's an intermittent working truck without much heavy loading I can't justify the extra $400 at this time for the full dual side 3" with single filter.
 
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