Wiped Out: NV4500 Input Shafts

[Sled Puller]

I picked these up at a transmission shop the other day. I thought you guys would like to see them. They were following the factory recommendations as far as lubricants. After the rebuild, they left the shop with non-factory recommended lubricants, some heavy duty parts and a pair of transmission coolers.



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[Don M]

Are you saying the failure was from the lubricant? I didnt think so!

It is apparent that the lubricant was not the prob. These shafts from a stock application?

Is the new lubricant gonna stop this? Nope.



Don~

 

[MCummings]

Ohhh, My eyes. The pain.



How did these fail exactly?? I know they didn't fail in a stock truck with stock lubricant. HOW?? My Dad has taken 3 Dodge trucks over 100,000 miles pulling 20,000+Lbs. Trailers and NEVER Changing the trannsmission lubricant.

My truck is the First truck he has ever let the transmission fluid be changed in (With AMSOIL no less) He hasn't ever broken anything on any of the Dodge trucks,, beswides clutches (Usually around 100K) then he just trades them in.



MerrickNJr

 

[Power Wagon]

Originally posted by Don M

Are you saying the failure was from the lubricant? I didnt think so!

It is apparent that the lubricant was not the prob. These shafts from a stock application?

Is the new lubricant gonna stop this? Nope.



Don~

Don, please don't try to start an argument here. MGM made his point without bashing anyone, and the post was sufficiently interesting on it's own to warrant it's existence.

 

[Fast 1]

If the truck is driven hard enough in 5th or 6th (overdrive) the torque that the mighty cummins puts out will put the transmission temps. uncomfortably high. When this happens you will loose a little oil from the transmission venting. With the transmission being a smidget low on oil, the input shafts may be the first to suffer given it's location. Just my . 02 worth. What I've pulled with my truck, probably more than I should, four quarts of lube don't cut it over the long haul in 90 degree outside temps.



Consider the cost of replacing one transmission. Parts, labor, loss of income due to downtime if your truck is your business. $$$$$$



I could have bought alot of other bombs with all the trannys I've had to replace.



Lets not forget about the 5th gear nut hassle also.



But, it's still an AWESOME TRUCK !!!!!!









Fast Coolers



Verlyn Fast

 

[Sled Puller]

MCummings,



What is your opinion on how they failed?



Anybody else want to share what they think caused this meltdown?



Gene

 

[Joseph Donnelly]

Standard Trans showed me a shaft that looked the same. They said the trans was run without lube or very low on lube. To melt the gears, they have to get very hot, and they probably won't while there is lube in there.

 

[Sled Puller]

So your saying that this is common Joe?

 

[MCummings]

Originally posted by Joseph Donnelly

Standard Trans showed me a shaft that looked the same. They said the trans was run without lube or very low on lube. To melt the gears, they have to get very hot, and they probably won't while there is lube in there.

My opinion EXACTLY



Input shafts usually only "snap" when the TQ limit is reached.



MerrickNJr

 

[illflem]

Discolored metal indicates they got very hot probably due to low fluid level.

 

[drawson]

I have seen this on many manual trans. This caused by low fluid and high demand use like towing. the gear gets super hot and crystalizes then is ground off.

 

[Sled Puller]

Low fluid seems to be a popular opinion here tonight. Lets try to figure out why/how it may have gotten low.



1) leaks.

You would think a Hotshotter would notice a leak, and keep careful watch on them, but it is possible they missed it and lost fluid.



2) Excessive heat, which came from Verlyns opinion below:

Originally posted by Fast 1

If the truck is driven hard enough in 5th or 6th (overdrive) the torque that the mighty cummins puts out will put the transmission temps. uncomfortably high. When this happens you will loose a little oil from the transmission venting. With the transmission being a smidget low on oil, the input shafts may be the first to suffer given it's location... ... ... ...

Fast Coolers

Verlyn Fast

Also, a quote from a past TDR article,

" ... . An overheated condition... happens between the gear faces with LUGGING OF HEAVY LOADS AND HAPPENS OVER TIME. "



3) possible breakdown of the fluid from above.

How hot does it have to get before the factory lube starts to break down?

 

[baby.driver]

My guess is low lube level, heavy load on a long uphill grade.

OK MGM what's the real story?



Jay

 

[BPINE]

Originally posted by MGM

How hot does it have to get before the factory lube starts to break down? [/B]

My trany went to 250 while pulling to May Madness with the outside temp at about 90. This was on Baker grade (it is long) lucky it was early in the day or it would have been even hotter outside. I was pulling 5th gear at about 60 to 65.



What do we think the maximum temp is and what should the change interval really be?



I am running Amsoil at this time and have been sense 30k and now have 75 k on the truck.

 

[Fast 1]

Whatever lube you use if you pull it hard enough four quarts is not enough. Why have they told us only to use castrol. Because It is supposed to keep it cooler under extreme conditions. If four quarts is supposed to do that, what will six quarts do. To me, four quarts was a joke, I needed more than that. Everything else on the truck performs beyond my expectations. No problems with the rear diffs, brakes or clutches. I get 100,000 miles out of every clutch and the same for the brakes. My truck and trailer grossed 12,600 lbs empty and up to 34,620 lbs loaded. Add in wind resistance pulling four cars on a 52ft of lower deck and 10 ft deck above the fifth wheel. Like I said, four quarts is a joke.



If I'm pulling 1/3 of a load a big rig would pull, I should I have 1/3 the manual transmission lube capacity that they have!

A big rigs transmission will hold 15 to 20 quarts and have a pump and a cooler. Lets take the average of 17 1/2 quarts divided by 1/3 = 5. 83 quarts. Interesting? That's just what your capacity is with FAST COOLERS. Hmmmmmm.



Verlyn Fast

 

[NVR FNSH]

Hmm, nice sales pitch going on here for Amsoil and Fastcoolers... .



Somebody some me some MANUAL trans fluid data regarding max temp & oil breakdown, please. Verlyn, I've asked you before (when you first came out with your coolers) and the 'data' you replied with was suspiciously similar to what is bantered about for AUTOMATICS. Don't get me wrong, I agree that more fluid capicity is better - up to a point. I just don't know where that point is and scaling from a big rig is cheap 'science' IMO.



Brian

 

[Sled Puller]

Those input shafts were not "cheap" science.



Where was I selling Amsoil?

You guys are paranoid!





If I were too install FAST Coolers on a new truck, and the transmission broke, could they void my warranty?



Gene

 

[JJW_ND]

Maybe not exactly the same..... The last cheby work truck (97) I had with their version of a NVG4500HD went 1,200 miles before it welded together. Not a drop in the trans from the factory. These transmissions are allot tougher then one thinks. But even the best of materials yeilds!. Ironically, the replacement transmission went to 30K and the rear seal between the transfer case failed allowing most all the transmission fluid to run into the TCase. This was on a warm ND day pulling about 14K up one of the few hills we have. Developed a very loud noise in every gear but 4th. Did not weld up like the first one but enough to just replace.



It is very interesting watching a temp gauge in one of these 5sp. I was pulling doubles in single digit temps tonight. Transmssion when running 20+ boost in 5th would finally reach 120 degrees. Running empty it wouldnt even get to 100. In 100 degree summer temps, this would have been 180 - 190 degreee transmssion temp. I have seen a 10 - 20 degree rise in temps when going with the wind. Air flow has a big effect on the trans temp. Dodge has their 5sp pretty expose as compared to Chebys. Speaking of chebbys. Wonder how how the trans oil is when you can't hold your had on the stick shift by the boot for more then a few seconds. Felt this several times on high speed WOT pulls through MT. When my Dodge 5sp was at its hotest based on the temp gauge it was luke warm by the boot.



jjw

ND

 

[NVR FNSH]

Originally posted by MGM

Those input shafts were not "cheap" science.



Where was I selling Amsoil?

You guys are paranoid!





If I were too install FAST Coolers on a new truck, and the transmission broke, could they void my warranty?



Gene

Gene those input shafts are evidence of a failure. What caused the failure is still open for discussion AFAIK.



You weren't 'selling' Amsoil per se. I read some of the comments (not necessarily MGM's) as 'this wouldn't have happened with a better fluid' - I took it to mean Amsoil.



I certainly hope that a dealer wouldn't try and void your warranty for installing the Fast Coolers. However, they certainly could make your life miserable if you were running Amsoil.



Brian

 

[Todd T]

My vote is some local-yocal dealer replaced those trannies for customers and NEVER filled them back up.



as in, Dry from the factory.