I posted this question in an older thread, but apparently no one is looking at those old treads anymore. I think that it is time for a fluid change in my transmission. I have searched all over the place for Valvoline 50 SAE gear oil, and keep coming up empty. Does anyone have a source for the proper fluid for this transmission? i am concerned that the lube shop that did the last fluid change did not use the correct fluid, and that may be contributing to my hard slightly notchy shifts. This may be a stupid question, but is the Valvoline 50 SAE motor oil the same oil? I do not think that it would have the correct additives, but I am not positive. Any help or links would be greatly appreciated. 

https://www.napaonline.com/en/p/VAA706035M

 

Local store has 5 gallons pails in stock. Very common supplied fluid used in logging trucks. Commonly used in all over the road trucks Eaton Fuller transmissions. 

Edited August 22, 20186 yr by Mopar1973Man

Ouch! I guess the 5 gallon bucket would solve any future supply issues for awhile. @Mopar1973Man, do you subscribe to the 6qts school of thought? i will be filling from the top of the transmission through the shift tower. 

1 minute ago, adamey1000 said:

do you subscribe to the 6qts school of thought?

 

No. Because even at 5 quarts it pushes out the vent on an NV4500. If you don't mind the smell and the constant slop running down the case you fine to overfill but it just going to push it out the vent. I just barely overfill even to cover my temp sensor in the fill plug. NV4500 is only a 4-quart transmission. 50 SAE is only sold in 5-gallon pails. Compared to $27 a quart for the factory fuild I would $50 a gallon now for the 50 SAE fluid. 19k miles left to go to 100k miles. on this transmission. I change my fluid beginning of summer. It got a fluid life of about 50k miles to about 75k miles. 

Here is the fluid that I always recommend. Lots of great reports. Around $13/qt if you can find a good dealer. 

 

https://www.amsoil.com/shop/by-product/transmission-fluid/manual/manual-transmission-and-transaxle-gear-lube-75w-90/?code=MTGQT-EA

1 hour ago, Mopar1973Man said:

 

No. Because even at 5 quarts it pushes out the vent on an NV4500. If you don't mind the smell and the constant slop running down the case you fine to overfill but it just going to push it out the vent. I just barely overfill even to cover my temp sensor in the fill plug. NV4500 is only a 4-quart transmission. 50 SAE is only sold in 5-gallon pails. Compared to $27 a quart for the factory fuild I would $50 a gallon now for the 50 SAE fluid. 19k miles left to go to 100k miles. on this transmission. I change my fluid beginning of summer. It got a fluid life of about 50k miles to about 75k miles. 

 

I agree, I never overfill my manual transmissions. This is what Spicer says about overfilling:

 http://Overfilling Do not overfill the transmission. This usually results in oil breakdown due to excessive heat and aeration form the churning action of the gears. Early breakdown of the oil will result in heavy varnish and sludge deposits that plug up oil ports and build up on splines and bearings.