# Transmission or Clutch Noise



## NelsonCnty (Jan 7, 2008)

Hi all,

I can't tell if this is a clutch or transmission noise. It happens in all gears except 4th (of course) so I'm guessing tranny. It happens intermittently on acceleration, sort of like a chirping or metal rubbing. It happens EVERY time when I let up on the gas while in gear (when the tranny is slowing the truck).

Turns out the gear oil had completely leaked out of the transmission. I filled it up today and took a short drive. Can't tell if it's much better or not, but maybe it'll take time to re-lubricate?

Any thoughts or advice is appreciated. Thanks!


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## rogoman (Dec 16, 2004)

You probably ran the tranny dry for a long time: permanent damage was done. You might try using Red Line's synthetic MT-90 75W90 GL-4 Gear Oil; it's an excellent gear oil and it just might quiet down some of the noise; otherwise the tranny will have to be rebuilt or replaced.


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## daniel-delarosa (Jan 1, 2014)

Id change the oil and see if there are any metal shavings in it...


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## NelsonCnty (Jan 7, 2008)

I was afraid of that. I've been thinking and I'm betting that when I had this tranny put in (it was second hand), the shop forgot to fill it with oil. I remember driving it away that day thinking that this trans had more of a whine/sound to it than the original. It was the following year that this new noise showed up. I've basically been driving it in 4th for a year (getting to 4th as quickly and easily as possible) and avoiding 5th altogether. I wonder how much longer I can get away with it...we'll find out!


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## jp2code (Jun 2, 2011)

rogoman said:


> You probably ran the tranny dry for a long time: permanent damage was done. You might try using Red Line's synthetic MT-90 75W90 GL-4 Gear Oil; it's an excellent gear oil and it just might quiet down some of the noise; otherwise the tranny will have to be rebuilt or replaced.


Red Line's MT-90 is really good stuff. My synchronizers were going out, and this oil helped me get into the gears much easier.

https://www.amazon.com/dp/B000CPCBEQ


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## NelsonCnty (Jan 7, 2008)

Thanks. I'm not having any difficulty getting into gears, it's just the weird scraping sound that I hear sometimes on acceleration and always when I decelerate in gear. Fifth gear is out of the question, it's noisy and rumbles.


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